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All questions of Respiratory System (BIO) for MCAT Exam
Interstitial cells or leydig cells are present between______.- a)Basal lamina
- b)Seminiferous tubules
- c)Tubuli recti
- d)Sertoli cells
Correct answer is option 'B'. Can you explain this answer?
Interstitial cells or leydig cells are present between______.
a)
Basal lamina
b)
Seminiferous tubules
c)
Tubuli recti
d)
Sertoli cells
|
Sathvika Tadri answered |
Interstitial cells or leydig cells are present between seminiferous tubules..they secrete androgens..mainly testosterone
Can you explain the answer of this question below:The yellowish coloured milk secreted from the breast shortly after birth of the baby is called?
- A:
Lactogen
- B:
Primary milk
- C:
Colostrum
- D:
None of these
The answer is c.
The yellowish coloured milk secreted from the breast shortly after birth of the baby is called?
Lactogen
Primary milk
Colostrum
None of these
|
Rohit Shah answered |
Colostrum is a thick and sticky, yellow to orange colored milk that is created by your breasts to give your baby the nutrition he needs immediately after birth. It is low in fat, high in carbohydrates and has a laxative effect on the baby which helps him pass the first meconium stools that are sitting in his intestines. This also helps get rid of the bile and helps lessen the chance of jaundice in your newborn.
Ovulation occurs on the ------ day of menstrual cycle. - a)08-10
- b)12-14
- c)14-16
- d)16-18
Correct answer is option 'C'. Can you explain this answer?
Ovulation occurs on the ------ day of menstrual cycle.
a)
08-10
b)
12-14
c)
14-16
d)
16-18
|
Maya Sengupta answered |
The release of ovum from ovary during menstrual cycle is is called ovulation. Ovulation occurs in the middle of menstrual cycle that is on 14-16th day of start of menstrual cycle.
Shortest phase of the menstrual cycle is______.- a)Ovulatory phase
- b)Menses
- c)Follicular phase
- d)Luteal phase
Correct answer is option 'A'. Can you explain this answer?
Shortest phase of the menstrual cycle is______.
a)
Ovulatory phase
b)
Menses
c)
Follicular phase
d)
Luteal phase
|
Priya Menon answered |
Menstrual cycle is divided into several phase starting from menses during which endometrium breaks and comes out through vagina for 4 to 5 days. Ovulatory phase occurs in the middle of menstrual cycle (14/15th day) during which egg is released.
Which one is the most likely reason of not occurring regular menstrual cycle?- a)Fertilization of ovum
- b)Retention of corpus luteum
- c)Maintenance of hypertropical endometrial lining
- d)Maintenance of high concentration of sex hormones
Correct answer is option 'A'. Can you explain this answer?
Which one is the most likely reason of not occurring regular menstrual cycle?
a)
Fertilization of ovum
b)
Retention of corpus luteum
c)
Maintenance of hypertropical endometrial lining
d)
Maintenance of high concentration of sex hormones
|
Sushant Goyal answered |
Menstrual cycles get stopped during pregnancy. Sometimes it becomes irregular due to stress and other hormonal activities of the body.
The cellular layer that disintegrates and regenerates again and again is _______.
- a)Dermis of skin
- b)Endometrium of uterus
- c)Cornea of eye
- d)Endometrium of blood vessels
Correct answer is option 'B'. Can you explain this answer?
The cellular layer that disintegrates and regenerates again and again is _______.
a)
Dermis of skin
b)
Endometrium of uterus
c)
Cornea of eye
d)
Endometrium of blood vessels
|
Rhea Sarkar answered |
- The functional layer of the human endometrium is a highly regenerative tissue undergoing monthly cycles of growth, differentiation, and shedding during a woman's reproductive years.
- Fluctuating levels of circulating estrogen and progesterone orchestrate this dramatic remodelling of human endometrium.
Hence, the correct option is B.
NCERT Reference: topic “MENSTRUAL CYCLE” of chapter: Human Reproduction.
NCERT Reference: topic “MENSTRUAL CYCLE” of chapter: Human Reproduction.
Hormone responsible for milk ejection after the birth of baby is:
- a)Progesterone
- b)vasopressin
- c)Estrogens
- d)Oxytocin
Correct answer is option 'D'. Can you explain this answer?
Hormone responsible for milk ejection after the birth of baby is:
a)
Progesterone
b)
vasopressin
c)
Estrogens
d)
Oxytocin
|
Naina Choudhary answered |
Hormone responsible for milk ejection after the birth of baby is oxytocin.
Explanation:
After the birth of a baby, the mother's body undergoes various hormonal changes that promote milk production and ejection. The primary hormone responsible for milk ejection is oxytocin, which is produced in the hypothalamus and released from the posterior pituitary gland.
When a baby suckles at the breast, nerve endings in the nipple and areola are stimulated, which triggers the release of oxytocin. Oxytocin then causes the smooth muscle cells in the milk ducts to contract, which pushes the milk out of the breast and into the baby's mouth. This process is known as the milk ejection reflex or let-down reflex.
Other hormones that are involved in milk production and ejection include:
- Prolactin: This hormone is produced in the anterior pituitary gland and stimulates milk production in the mammary glands.
- Estrogens: These hormones are produced in the ovaries and play a role in breast development and milk production.
- Progesterone: This hormone is produced in the ovaries and plays a role in preparing the breast for milk production.
However, in terms of milk ejection specifically, oxytocin is the primary hormone involved.
Explanation:
After the birth of a baby, the mother's body undergoes various hormonal changes that promote milk production and ejection. The primary hormone responsible for milk ejection is oxytocin, which is produced in the hypothalamus and released from the posterior pituitary gland.
When a baby suckles at the breast, nerve endings in the nipple and areola are stimulated, which triggers the release of oxytocin. Oxytocin then causes the smooth muscle cells in the milk ducts to contract, which pushes the milk out of the breast and into the baby's mouth. This process is known as the milk ejection reflex or let-down reflex.
Other hormones that are involved in milk production and ejection include:
- Prolactin: This hormone is produced in the anterior pituitary gland and stimulates milk production in the mammary glands.
- Estrogens: These hormones are produced in the ovaries and play a role in breast development and milk production.
- Progesterone: This hormone is produced in the ovaries and plays a role in preparing the breast for milk production.
However, in terms of milk ejection specifically, oxytocin is the primary hormone involved.
Conditional reabsorption of sodium ions and water takes place in- a)DCT
- b)Collecting duct
- c)Henle’s loop
- d)PCT
Correct answer is option 'A'. Can you explain this answer?
Conditional reabsorption of sodium ions and water takes place in
a)
DCT
b)
Collecting duct
c)
Henle’s loop
d)
PCT
|
Ayush Chavan answered |
Conditional reabsorption of sodium ions and water takes place in distal convoluted tubule.
The number of polar bodies formed during oogenesis in human being is:
- a)2
- b)3
- c)1
- d)Both 2 and 3.
Correct answer is option 'D'. Can you explain this answer?
The number of polar bodies formed during oogenesis in human being is:
a)
2
b)
3
c)
1
d)
Both 2 and 3.
|
Raj Yadav answered |
Polar bodies formed during oogenesis in humans
- During human oogenesis, three polar bodies are created.
- Polar bodies are tiny cytoplasmic exclusion structures that form to contain extra DNA produced during oocyte meiosis, which occurs after sperm fertilization.
- The zygote contains roughly 2-3 polar bodies, which are derived from the oocyte.
- This figure is determined by whether or not the first polar body (produced during meiosis I) splits during meiosis II.
- Excess DNA generated from reductive division makes up such an exclusion body (2nd and 3rd polar bodies are formed from meiosis II at the time of fertilization).
- Such polar bodies do not contribute to the zygote's, foetus', or embryo's future genetic complement.
In which part of nephron, reabsorption of glucose is maximum from filtrate?- a)Henle’s loop
- b)Distal convoluted tubule
- c)seminiferous tubules
- d)Proximal convoluted tubule
Correct answer is option 'D'. Can you explain this answer?
In which part of nephron, reabsorption of glucose is maximum from filtrate?
a)
Henle’s loop
b)
Distal convoluted tubule
c)
seminiferous tubules
d)
Proximal convoluted tubule
|
Shyamal Modak. answered |
The ans is D).PCT.
Acc. to NCERT nearly all the essential nutrients and 70-80% of the electrolytes and water are reabsorbed by this segment.i.e. PCT
Acc. to NCERT nearly all the essential nutrients and 70-80% of the electrolytes and water are reabsorbed by this segment.i.e. PCT
Which of the following hormone is produced in female only during pregnancy?
- a)Testosterone
- b)Human chorionic gonadotropin hormone (hCG).
- c)Progesterone
- d)Estrogen
Correct answer is option 'B'. Can you explain this answer?
Which of the following hormone is produced in female only during pregnancy?
a)
Testosterone
b)
Human chorionic gonadotropin hormone (hCG).
c)
Progesterone
d)
Estrogen
|
Dev Patel answered |
- It is made almost exclusively in the placenta.
- hCG hormone levels found in the mother's blood and urine, rise a lot during the first trimester.
- hCG Maintains the corpus luteum throughout the early stages of pregnancy. It is used to detect pregnancy.
Hence, the correct option is B.
NCERT Reference: Page no. 53 of topic “3.6 PREGNANCY AND EMBRYONIC DEVELOPMENT” of chapter 3.
The filtration fraction is the ratio of GFR to RPF where both the values are in ml/min and FF is expressed in percentage. Calculate FF for a normal adult human being, if RPF= 600ml/min :- a)2.08%
- b)20.73%
- c)10.38%
- d)20.83%
Correct answer is option 'D'. Can you explain this answer?
The filtration fraction is the ratio of GFR to RPF where both the values are in ml/min and FF is expressed in percentage. Calculate FF for a normal adult human being, if RPF= 600ml/min :
a)
2.08%
b)
20.73%
c)
10.38%
d)
20.83%
|
Janhavi Rane answered |
FF = (125/600)*100 = 20.83%
The following substances are the excretory products in animals. Choose the least toxic form among them?- a)Urea
- b)Uric acid
- c) Ammonia
- d)Carbon dioxide
Correct answer is option 'B'. Can you explain this answer?
The following substances are the excretory products in animals. Choose the least toxic form among them?
a)
Urea
b)
Uric acid
c)
Ammonia
d)
Carbon dioxide
|
Anshu Saha answered |
The least toxic form among the excretory products in animals is uric acid.
Explanation:
• Animals excrete waste products that are formed during metabolic processes.
• The excretory products are mainly classified into three types: ammonia, urea, and uric acid.
• Ammonia is highly toxic and water-soluble. It is excreted by aquatic animals, but not by terrestrial animals because of its toxicity.
• Urea is less toxic than ammonia and water-soluble. It is excreted by most terrestrial animals, including humans.
• Uric acid is the least toxic form among the three. It is insoluble in water and is excreted in the form of a paste or a solid.
• Uric acid is the excretory product of birds, reptiles, and insects. It is also excreted by some other animals, such as snails and spiders.
• Uric acid is less toxic than ammonia and urea because it requires less water for its excretion.
• The excretion of uric acid conserves water, which is essential for survival in arid environments.
• In humans, excess uric acid can lead to gout, a painful condition caused by the deposition of uric acid crystals in the joints.
Therefore, uric acid is the least toxic form among the excretory products in animals.
Explanation:
• Animals excrete waste products that are formed during metabolic processes.
• The excretory products are mainly classified into three types: ammonia, urea, and uric acid.
• Ammonia is highly toxic and water-soluble. It is excreted by aquatic animals, but not by terrestrial animals because of its toxicity.
• Urea is less toxic than ammonia and water-soluble. It is excreted by most terrestrial animals, including humans.
• Uric acid is the least toxic form among the three. It is insoluble in water and is excreted in the form of a paste or a solid.
• Uric acid is the excretory product of birds, reptiles, and insects. It is also excreted by some other animals, such as snails and spiders.
• Uric acid is less toxic than ammonia and urea because it requires less water for its excretion.
• The excretion of uric acid conserves water, which is essential for survival in arid environments.
• In humans, excess uric acid can lead to gout, a painful condition caused by the deposition of uric acid crystals in the joints.
Therefore, uric acid is the least toxic form among the excretory products in animals.
A renal corpuscle is :- a)malpighian body
- b)malpighian tubule
- c)nephron
- d)Bowman’s capsule
Correct answer is option 'A'. Can you explain this answer?
A renal corpuscle is :
a)
malpighian body
b)
malpighian tubule
c)
nephron
d)
Bowman’s capsule
|
Ayush Choudhury answered |
Renal corpuscle, also called malpighian body, filtration unit of vertebrate nephrons, functional units of the kidney. It consists of a knot of capillaries (glomerulus) surrounded by a double-walled capsule (Bowman's capsule) that opens into a tubule.
A Human female reaches menopause around the age of_____.- a)25 years
- b)70 years
- c)50 years
- d)15 years
Correct answer is option 'C'. Can you explain this answer?
A Human female reaches menopause around the age of_____.
a)
25 years
b)
70 years
c)
50 years
d)
15 years
|
|
Aravind Joshi answered |
Menopause is a natural biological process that marks the end of a woman's reproductive years. During menopause, the ovaries stop producing eggs and the levels of estrogen and progesterone hormones decline. Menopause is a gradual process that usually occurs between the ages of 45 and 55, with the average age being 51.
Explanation:
• Menopause is a natural biological process that occurs in women.
• It marks the end of a woman's reproductive years.
• During this process, the ovaries stop producing eggs and the levels of estrogen and progesterone hormones decline.
• Menopause is a gradual process that usually occurs between the ages of 45 and 55.
• The average age of menopause is 51 years.
• Menopause can occur earlier or later than the average age depending on various factors, such as genetics, lifestyle, and medical conditions.
• Menopause can occur as early as 40 years or as late as 60 years.
• Menopause is confirmed after a woman has gone 12 consecutive months without a menstrual period.
Explanation:
• Menopause is a natural biological process that occurs in women.
• It marks the end of a woman's reproductive years.
• During this process, the ovaries stop producing eggs and the levels of estrogen and progesterone hormones decline.
• Menopause is a gradual process that usually occurs between the ages of 45 and 55.
• The average age of menopause is 51 years.
• Menopause can occur earlier or later than the average age depending on various factors, such as genetics, lifestyle, and medical conditions.
• Menopause can occur as early as 40 years or as late as 60 years.
• Menopause is confirmed after a woman has gone 12 consecutive months without a menstrual period.
During which month of pregnancy first movement of fetus is observed?- a)Sixth month
- b)Fourth month
- c)Fifth month
- d)Third month
Correct answer is option 'C'. Can you explain this answer?
During which month of pregnancy first movement of fetus is observed?
a)
Sixth month
b)
Fourth month
c)
Fifth month
d)
Third month
|
Saranya Joshi answered |
The correct answer is option C, i.e., fifth month.
Explanation:
The first movement of the fetus is called quickening. It is the first noticeable movement of the fetus by the mother. Quickening is the first sign that the pregnancy is progressing as expected. It usually occurs between the 16th and 25th weeks of pregnancy. However, it is most commonly felt around the 20th week of pregnancy, which is the fifth month.
During the first trimester, the fetus is too small and underdeveloped to produce movements that can be felt by the mother. The fetal movements at this stage are mostly uncoordinated and involuntary.
During the second trimester, the fetus grows and becomes more active. The movements become more coordinated and frequent. By the end of the fifth month, the fetus is about 10 inches long and weighs around 1 pound. The movements of the fetus become more pronounced and can be felt by the mother.
In summary, the first movement of the fetus can be observed in the fifth month of pregnancy, which is around the 20th week.
Explanation:
The first movement of the fetus is called quickening. It is the first noticeable movement of the fetus by the mother. Quickening is the first sign that the pregnancy is progressing as expected. It usually occurs between the 16th and 25th weeks of pregnancy. However, it is most commonly felt around the 20th week of pregnancy, which is the fifth month.
During the first trimester, the fetus is too small and underdeveloped to produce movements that can be felt by the mother. The fetal movements at this stage are mostly uncoordinated and involuntary.
During the second trimester, the fetus grows and becomes more active. The movements become more coordinated and frequent. By the end of the fifth month, the fetus is about 10 inches long and weighs around 1 pound. The movements of the fetus become more pronounced and can be felt by the mother.
In summary, the first movement of the fetus can be observed in the fifth month of pregnancy, which is around the 20th week.
During urine formation, the tubular cells secrete ------------------ into the filtrate.- a)Potassium ions and ammonia
- b)Hydrogen ions and potassium ions
- c)Hydrogen ions, potassium ions and ammonia
- d)Only ammonia
Correct answer is option 'C'. Can you explain this answer?
During urine formation, the tubular cells secrete ------------------ into the filtrate.
a)
Potassium ions and ammonia
b)
Hydrogen ions and potassium ions
c)
Hydrogen ions, potassium ions and ammonia
d)
Only ammonia
|
Kunal Rane answered |
During urine formation, the tubular cells secrete substances like hydrogen ions, potassium ions and ammonia into the filtrate.
Which of the following control the function of Sertoli cell?- a)FSH
- b)Estrogens
- c)Testosterone
- d)ACTH
Correct answer is option 'A'. Can you explain this answer?
Which of the following control the function of Sertoli cell?
a)
FSH
b)
Estrogens
c)
Testosterone
d)
ACTH
|
Gaurav Kumar answered |
FSH (follicle stimulating hormone) stimulates Sertoli cells to secrete spermatogenic substance. Sertoli cells function as nurse cells for differentiating spermatozoa.
Can you explain the answer of this question below:Each testis has about 250 compartment called as____.
- A:
Oogonia
- B:
Seminiferous tubules
- C:
Lactiferous lobules
- D:
Testicular lobules
The answer is d.
Each testis has about 250 compartment called as____.
Oogonia
Seminiferous tubules
Lactiferous lobules
Testicular lobules
|
Pooja Pillai answered |
Each testis contains about 250 compartments called testicular lobules. Each testicular lobule contains one to three highly coiled seminiferous tubules that produce sperms.
Beginning of menstrual cycle is called as ___.- a)Ovulation
- b)Oogenesis
- c)Menarche
- d)Menopause
Correct answer is option 'C'. Can you explain this answer?
Beginning of menstrual cycle is called as ___.
a)
Ovulation
b)
Oogenesis
c)
Menarche
d)
Menopause
|
|
NEET Aspirant 2021 answered |
The first menstrual period occurs after the onset of pubertal growth, and is called menarche.
so the correct answer is option c) Menarche
so the correct answer is option c) Menarche
Which blood vessel takes blood away from the kidney? - a)Renal portal vein
- b)Renal vein
- c)Afferent arteriole
- d)Efferent arteriole
Correct answer is option 'B'. Can you explain this answer?
Which blood vessel takes blood away from the kidney?
a)
Renal portal vein
b)
Renal vein
c)
Afferent arteriole
d)
Efferent arteriole
|
Ramesh Chand answered |
The renal vein takes blood away from the kidney. The process starts with renal artery which enters the kidney as afferent arteriole. It carries the urea loaded blood into the glomerulus of the kidney. The blood is filtered by the glomerulus into the Bowman's capsule and runs parallel to the loop of Henle. The urea is absorbed into the nephric filtrate by the process of tubular secretion in the loop of Henle, distal convulated tubule and collecting duct. The process of tubular secretion helps to secrete the urea from the blood to the collecting duct which is finally excreted in form of urine. The purified blood comes from the kidney through the renal vein and drained into vena cava outside kidney.
So, the correct answer is 'Renal vein'.
So, the correct answer is 'Renal vein'.
Which of the following is formed first out of the following in growing foetus: hairs, limbs and digits, heart, eye lids?- a)Eye lids
- b)Limbs and digits
- c)Heart
- d)Hairs on head
Correct answer is option 'C'. Can you explain this answer?
Which of the following is formed first out of the following in growing foetus: hairs, limbs and digits, heart, eye lids?
a)
Eye lids
b)
Limbs and digits
c)
Heart
d)
Hairs on head
|
|
Deepanshi Mishra answered |
In growing foetus first of all heart is formed. Doctor diagnose the foetus by hearing the heart sound firstly, after that other organs develope. Cardiovascular developments starts at 3rd to 6th week of pregnancy. Heart beat can be heard at starting of 4th week.
Immediately after ovulation, the mammalian egg is covered by a membrane known as- a)chorion
- b)zona pellucida
- c)corona radiata
- d)vitelline membrane
Correct answer is option 'C'. Can you explain this answer?
Immediately after ovulation, the mammalian egg is covered by a membrane known as
a)
chorion
b)
zona pellucida
c)
corona radiata
d)
vitelline membrane
|
|
Navya Tiwari answered |
The mammalian egg is covered by a series of membranes that protect it and aid in fertilization. Immediately after ovulation, the egg is surrounded by a membrane known as the zona pellucida.
Explanation:
Zona Pellucida:
- The zona pellucida is a glycoprotein layer that forms around the mammalian egg immediately after ovulation.
- It is secreted by the egg as it travels through the oviduct towards the uterus.
- The zona pellucida is composed of three layers: an outer layer, a middle layer, and an inner layer.
- The outer layer is the thinnest and is composed of glycoproteins that help to bind sperm to the zona pellucida.
- The middle layer is the thickest and is composed of a matrix of glycoproteins and proteoglycans.
- The inner layer is the thinnest and is composed of glycoproteins that are involved in the sperm-binding process.
Functions of the Zona Pellucida:
- The zona pellucida plays a key role in fertilization, as it is the first barrier that sperm must penetrate in order to reach the egg.
- The glycoproteins on the surface of the zona pellucida bind to specific receptors on the surface of sperm, allowing them to attach and begin the process of fertilization.
- Once sperm have attached to the zona pellucida, they release enzymes that help to dissolve the outer layer, allowing them to penetrate to the egg.
Other Membranes Surrounding the Egg:
- In addition to the zona pellucida, the mammalian egg is also surrounded by a layer of follicle cells called the corona radiata.
- The corona radiata is composed of cells that have surrounded the egg within the follicle and are released along with the egg during ovulation.
- The corona radiata provides additional protection to the egg and helps to guide sperm towards the zona pellucida.
Conclusion:
In conclusion, immediately after ovulation, the mammalian egg is covered by a membrane known as the zona pellucida. This glycoprotein layer plays a key role in fertilization by allowing sperm to bind to its surface and penetrate to the egg. The corona radiata, another layer of follicle cells, also surrounds the egg and provides additional protection during fertilization.
Explanation:
Zona Pellucida:
- The zona pellucida is a glycoprotein layer that forms around the mammalian egg immediately after ovulation.
- It is secreted by the egg as it travels through the oviduct towards the uterus.
- The zona pellucida is composed of three layers: an outer layer, a middle layer, and an inner layer.
- The outer layer is the thinnest and is composed of glycoproteins that help to bind sperm to the zona pellucida.
- The middle layer is the thickest and is composed of a matrix of glycoproteins and proteoglycans.
- The inner layer is the thinnest and is composed of glycoproteins that are involved in the sperm-binding process.
Functions of the Zona Pellucida:
- The zona pellucida plays a key role in fertilization, as it is the first barrier that sperm must penetrate in order to reach the egg.
- The glycoproteins on the surface of the zona pellucida bind to specific receptors on the surface of sperm, allowing them to attach and begin the process of fertilization.
- Once sperm have attached to the zona pellucida, they release enzymes that help to dissolve the outer layer, allowing them to penetrate to the egg.
Other Membranes Surrounding the Egg:
- In addition to the zona pellucida, the mammalian egg is also surrounded by a layer of follicle cells called the corona radiata.
- The corona radiata is composed of cells that have surrounded the egg within the follicle and are released along with the egg during ovulation.
- The corona radiata provides additional protection to the egg and helps to guide sperm towards the zona pellucida.
Conclusion:
In conclusion, immediately after ovulation, the mammalian egg is covered by a membrane known as the zona pellucida. This glycoprotein layer plays a key role in fertilization by allowing sperm to bind to its surface and penetrate to the egg. The corona radiata, another layer of follicle cells, also surrounds the egg and provides additional protection during fertilization.
How many sperms are formed by 4 primary spermatocytes? - a)1
- b)4
- c)32
- d)16
Correct answer is option 'D'. Can you explain this answer?
How many sperms are formed by 4 primary spermatocytes?
a)
1
b)
4
c)
32
d)
16
|
|
Juhi Reddy answered |
Each primary spermatocyte undergoes first meiotic division to produce 2 secondary spermatocytes, which further proceeds to second meiotic division to form 2 spermatids. So, each primary spermatocyte produces 4 sperms.
The following substances are the excretory products in animals. Choose the least toxic form among them?- a)Urea
- b)Uric acid
- c)Ammonia
- d)Carbon dioxide
Correct answer is option 'B'. Can you explain this answer?
The following substances are the excretory products in animals. Choose the least toxic form among them?
a)
Urea
b)
Uric acid
c)
Ammonia
d)
Carbon dioxide
|
|
Lekhana Licchi answered |
Based on toxicity-ammonia>urea>uric acid.
Uric acid is least toxic and least soluble in water... And it requires less water for excretion.
Uric acid is least toxic and least soluble in water... And it requires less water for excretion.
pH of urine under healthy conditions is :- a)slightly alkaline
- b)neutral
- c)highly alkaline
- d)slightly acidic
Correct answer is option 'D'. Can you explain this answer?
pH of urine under healthy conditions is :
a)
slightly alkaline
b)
neutral
c)
highly alkaline
d)
slightly acidic
|
Soumya Ahuja answered |
The pH of urine under healthy conditions is slightly less than 7 so, slightly acidic in nature.
Which of the following arise from endoderm?- a)Eye
- b)Heart
- c)Pigment cells
- d)Lungs
Correct answer is option 'D'. Can you explain this answer?
Which of the following arise from endoderm?
a)
Eye
b)
Heart
c)
Pigment cells
d)
Lungs
|
|
Anjali Iyer answered |
Ectoderm is the germ layer that develops primarily into skin and neural tissue. Mesoderm primarily develops into muscle tissues and red blood cells. Endoderm develops into many of the internal organs including the gastrointestinal tract, respiratory tract, and endocrine system.
In sectional view of female reproductive system, which one is correctly labeled?
- a)Infundibulum(IV), Perimetrium(V)
- b)Fimbriae(V), Endometrium(I)
- c)Infundibulum(III), Fimbriae(IV)
- d)Uterus(II), Ovary(III)
Correct answer is option 'C'. Can you explain this answer?
In sectional view of female reproductive system, which one is correctly labeled?
a)
Infundibulum(IV), Perimetrium(V)
b)
Fimbriae(V), Endometrium(I)
c)
Infundibulum(III), Fimbriae(IV)
d)
Uterus(II), Ovary(III)
|
|
Sakshi Kasture answered |
This is the same diagram in ncert and there u will get all the names. finger like projections called as fimbre & part next of fimbre called as infundibulum
Blood enters glomerular capillaries through _____ arteriole and leaves through _____ arteriole:- a)efferent, afferent
- b)radial, collecting
- c)distributing, collecting
- d)afferent, efferent
Correct answer is option 'D'. Can you explain this answer?
Blood enters glomerular capillaries through _____ arteriole and leaves through _____ arteriole:
a)
efferent, afferent
b)
radial, collecting
c)
distributing, collecting
d)
afferent, efferent
|
|
Rohan Singh answered |
Our nervous system has different types of neurons that are constantly at work. Neurons that receive information from our sensory organs (e.g. eye, skin) and transmit this input to the central nervous system are called afferent neurons. Neurons that send impulses from the central nervous system to your limbs and organs are called efferent neurons.
Therefore, as the afferent neurons convey the sensory stimulus to the brain (like burning sensation of a candle), the efferent neurons convey the motor stimulus to the muscles (moving the hand away from the candle). To sum it up: Afferent = Receive and Efferent = Act.
The tracts that are conveying sensations up to the brain are also referred to as the ascending tracts. Going in the opposite direction than the ascending tracts, the tracts linking the brain to all the muscles and organs of the body are called descending tracts.
Which types of fibers are damaged after a spinal cord injury determine the individual failures. If motor (= efferent) fibers are destroyed, you are not able to lift your leg, because the command can’t be transmitted from the brain to the muscles in the leg. If sensory (= afferent) fibers are affected, you and your brain won’t be notified by the sensory organs, e.g. if somebody strikes your leg. In fact, mostly a combination of efferent and afferent fibers is damaged after a spinal cord injury.
The hormone with enzymatic action which catalyses conversion of angiotensinogen into angiotensin is :- a)ANF
- b)Renin
- c)JFA
- d)Aldosterone
Correct answer is option 'B'. Can you explain this answer?
The hormone with enzymatic action which catalyses conversion of angiotensinogen into angiotensin is :
a)
ANF
b)
Renin
c)
JFA
d)
Aldosterone
|
|
Sapna Patel answered |
Angiotensin is produced by the action of renin (an enzyme produced by the kidneys) on a protein called angiotensinogen, which is formed by the liver.
A human female is born with a million of primary oocytes at the time of birth. How many eggs get a chance to mature?
- a)About 1000
- b)More than 500
- c)About 1500
- d)Some 500
Correct answer is option 'D'. Can you explain this answer?
A human female is born with a million of primary oocytes at the time of birth. How many eggs get a chance to mature?
a)
About 1000
b)
More than 500
c)
About 1500
d)
Some 500
|
|
Jithin Unni answered |
Answer:
A human female is born with a million of primary oocytes, which are immature eggs. However, only a small fraction of these oocytes will actually mature into eggs that can be fertilized. The process of egg maturation is called oogenesis and it takes place in the ovaries.
Factors Affecting Egg Maturation:
Several factors influence how many eggs get a chance to mature, including:
- Hormonal signals from the pituitary gland
- The age of the female
- Environmental factors such as stress, diet, and exposure to toxins
Process of Egg Maturation:
The process of egg maturation begins at puberty when the pituitary gland starts producing hormones that stimulate the ovaries. Each month, several immature oocytes begin to mature in response to these hormonal signals. However, only one of these oocytes will actually reach full maturity and be released during ovulation.
Number of Eggs Matured:
On average, a human female will release about 400-500 mature eggs during her reproductive lifetime. This means that out of the million primary oocytes that are present at birth, only a small fraction will actually mature into eggs that can be fertilized.
Conclusion:
Therefore, the correct answer to the question is option 'D', which states that about 500 eggs get a chance to mature.
A human female is born with a million of primary oocytes, which are immature eggs. However, only a small fraction of these oocytes will actually mature into eggs that can be fertilized. The process of egg maturation is called oogenesis and it takes place in the ovaries.
Factors Affecting Egg Maturation:
Several factors influence how many eggs get a chance to mature, including:
- Hormonal signals from the pituitary gland
- The age of the female
- Environmental factors such as stress, diet, and exposure to toxins
Process of Egg Maturation:
The process of egg maturation begins at puberty when the pituitary gland starts producing hormones that stimulate the ovaries. Each month, several immature oocytes begin to mature in response to these hormonal signals. However, only one of these oocytes will actually reach full maturity and be released during ovulation.
Number of Eggs Matured:
On average, a human female will release about 400-500 mature eggs during her reproductive lifetime. This means that out of the million primary oocytes that are present at birth, only a small fraction will actually mature into eggs that can be fertilized.
Conclusion:
Therefore, the correct answer to the question is option 'D', which states that about 500 eggs get a chance to mature.
In which part of sperm, mitochondria are present?- a)Head
- b)Middle piece
- c)Tail
- d)Neck
Correct answer is option 'B'. Can you explain this answer?
In which part of sperm, mitochondria are present?
a)
Head
b)
Middle piece
c)
Tail
d)
Neck
|
|
Jaya Chavan answered |
Mitochondria are present in the middle piece of the sperm.
Explanation:
The sperm is composed of three parts: head, middle piece, and tail.
1. Head:
The head of the sperm contains the nucleus which carries genetic material in the form of DNA.
2. Middle piece:
The middle piece of the sperm contains a large number of mitochondria. Mitochondria are organelles that produce energy in the form of ATP (adenosine triphosphate) for the movement of the sperm.
3. Tail:
The tail of the sperm is also known as the flagellum. It provides motility to the sperm and helps in the movement towards the egg.
Therefore, the correct answer is option 'B' that mitochondria are present in the middle piece of the sperm.
Explanation:
The sperm is composed of three parts: head, middle piece, and tail.
1. Head:
The head of the sperm contains the nucleus which carries genetic material in the form of DNA.
2. Middle piece:
The middle piece of the sperm contains a large number of mitochondria. Mitochondria are organelles that produce energy in the form of ATP (adenosine triphosphate) for the movement of the sperm.
3. Tail:
The tail of the sperm is also known as the flagellum. It provides motility to the sperm and helps in the movement towards the egg.
Therefore, the correct answer is option 'B' that mitochondria are present in the middle piece of the sperm.
Seminal plasma in human males is rich in_____.- a)Fructose and Calcium
- b)Ribose and Potassium
- c)DNA and testosterone
- d)Glucose and Calcium
Correct answer is 'A'. Can you explain this answer?
Seminal plasma in human males is rich in_____.
a)
Fructose and Calcium
b)
Ribose and Potassium
c)
DNA and testosterone
d)
Glucose and Calcium
|
|
Rahul answered |
The male accessory glands include paired seminal vesicles, a prostate and paired bulbourethral gland. Secretions of these glands constitute the seminal plasma which is rich in Fructose calcium and certain enzymes
Which of the following is not a part of glomerular filtrate?- a)globulins
- b)inorganic salts
- c)glucose
- d)creatinine
Correct answer is option 'A'. Can you explain this answer?
Which of the following is not a part of glomerular filtrate?
a)
globulins
b)
inorganic salts
c)
glucose
d)
creatinine
|
Maheshwar Saini answered |
Glomerular filtrate contains glucose, inorganic salts and creatinine but it do not contain globulins protein.
Read the following :
i. Infants and toddlers are often under habit of bed wetting since micturition is a reflex process.
ii. Adults and grown up children can control this reflex process, voluntarily to some extent.- a)both are correct
- b)Statement i) is correct and ii) is wrong
- c)both are wrong
- d)Statement i) is wrong and ii) is correct
Correct answer is option 'A'. Can you explain this answer?
Read the following :
i. Infants and toddlers are often under habit of bed wetting since micturition is a reflex process.
ii. Adults and grown up children can control this reflex process, voluntarily to some extent.
i. Infants and toddlers are often under habit of bed wetting since micturition is a reflex process.
ii. Adults and grown up children can control this reflex process, voluntarily to some extent.
a)
both are correct
b)
Statement i) is correct and ii) is wrong
c)
both are wrong
d)
Statement i) is wrong and ii) is correct
|
Shivani Tiwari answered |
The process of release of urine is called micturition and the neural mechanism causing it is called the micturition reflex. Adults and grown up children can control the reflex process of micturition voluntarily to some extent.
Acrosome is filled with _________.- a)Lipids
- b)Hormones
- c)Enzymes
- d)None of the above
Correct answer is option 'C'. Can you explain this answer?
Acrosome is filled with _________.
a)
Lipids
b)
Hormones
c)
Enzymes
d)
None of the above
|
Hansa Sharma answered |
- The head of mature mammalian sperm is made of elongated nucleus covered by acrosome.
- The acrosome is filled with hydrolytic enzymes that help in fertilization of ovum.
- These enzymes called sperm lysins that dissolve the membranes enveloping the ovum and help the sperm cell to enter the ovum by penetrating egg membrane.
Testosterone is secreted by____.- a)Sertoli cells
- b)Leydig cells
- c)Kupffer cells
- d)Mast cells
Correct answer is option 'B'. Can you explain this answer?
Testosterone is secreted by____.
a)
Sertoli cells
b)
Leydig cells
c)
Kupffer cells
d)
Mast cells
|
|
Soumya Dyavanagoudar answered |
Leydig cells are interstial cells present in the testis which produce testosterone .FSH stimulates the production of testosterone
Fixing up of blastocyst in the wall of the uterus is- a)Impregnation
- b)Placentation
- c)Implantation
- d)Fertilization
Correct answer is option 'C'. Can you explain this answer?
Fixing up of blastocyst in the wall of the uterus is
a)
Impregnation
b)
Placentation
c)
Implantation
d)
Fertilization
|
|
Ananya Das answered |
The fixing of the blastocyst in the wall of the uterus is known as implantation. The implantation takes place after seven days of fertilization.
`
All of the following organs help in excretion except :- a)Liver
- b)Lungs
- c)Heart
- d)Skin
Correct answer is option 'C'. Can you explain this answer?
All of the following organs help in excretion except :
a)
Liver
b)
Lungs
c)
Heart
d)
Skin
|
|
Sapna Patel answered |
The function of heart is different from the rest options in a way that heart is an organ that pumps blood throughout
the body tissues and removing carbon dioxide and other wastes. And hence does not helps in excretion.
Sertoli cells present in the testis act as _____.- a)Germ cell
- b)Nurse cell
- c)Protective cell
- d)Receptor cell
Correct answer is option 'B'. Can you explain this answer?
Sertoli cells present in the testis act as _____.
a)
Germ cell
b)
Nurse cell
c)
Protective cell
d)
Receptor cell
|
|
Pooja Mehta answered |
Nurse cells are specialized macrophages residing in the bone marrow that assist in the development of red blood cells. They absorb the nuclei of immature red blood cells and may provide growth factors to help the red blood cells mature.
The middle layer of uterus is thick muscular myometrium that help in_________.- a)Release of ovum from ovary.
- b)Release of female hormones.
- c)Cyclic change during menstrual cycle.
- d)Strong contraction during delivery of the baby.
Correct answer is option 'D'. Can you explain this answer?
The middle layer of uterus is thick muscular myometrium that help in_________.
a)
Release of ovum from ovary.
b)
Release of female hormones.
c)
Cyclic change during menstrual cycle.
d)
Strong contraction during delivery of the baby.
|
|
Awantika Gupta answered |
Option D is correct that is myometrium causes vigorous contractions during delivery.
In human females, meiosis-ll is not completed until?
- a)Puberty
- b)Fertilisation
- c)Uterine implantation
- d)Birth
Correct answer is option 'B'. Can you explain this answer?
In human females, meiosis-ll is not completed until?
a)
Puberty
b)
Fertilisation
c)
Uterine implantation
d)
Birth
|
|
Suresh Iyer answered |
- At the end of meiosis I females have two daughter cells and meiosis II only occurs if and when the fertilization occurs by the sperm cell.
- Meiosis II starts after the sperm proceeds fertilization process in female
- Meiosis II starts after the sperm proceeds fertilization process in female
During micturition, the muscles of urinary bladder and urethral sphincters will- a)contract and relax respectively.
- b)none of these
- c)show fatigue
- d)relaxand contract respectively.
Correct answer is option 'A'. Can you explain this answer?
During micturition, the muscles of urinary bladder and urethral sphincters will
a)
contract and relax respectively.
b)
none of these
c)
show fatigue
d)
relaxand contract respectively.
|
Jyoti Desai answered |
Micturition is the process of voiding urine from the body. During this process, the muscles of the urinary bladder and urethral sphincters play a crucial role in controlling the flow of urine. The correct answer to the given question is option 'A', i.e., the muscles of the urinary bladder will contract, and the urethral sphincters will relax.
Explanation:
The process of micturition involves the following steps:
1. Filling of the urinary bladder: The urinary bladder is a muscular sac that stores urine until it is eliminated from the body. As the bladder fills with urine, its walls stretch, and the pressure inside the bladder increases.
2. Sensory input to the spinal cord: The stretch receptors in the bladder walls send signals to the spinal cord, indicating that the bladder is full.
3. Activation of the micturition reflex: The spinal cord processes the sensory input and generates a reflex response that activates the muscles of the bladder and urethral sphincters.
4. Contraction of the bladder muscles: The muscles of the bladder wall contract, forcing urine out of the bladder and into the urethra.
5. Relaxation of the urethral sphincters: The urethral sphincters, which are circular muscles that control the flow of urine through the urethra, relax, allowing urine to pass out of the body.
Therefore, during micturition, the muscles of the urinary bladder will contract, and the urethral sphincters will relax to allow the flow of urine out of the body.
Explanation:
The process of micturition involves the following steps:
1. Filling of the urinary bladder: The urinary bladder is a muscular sac that stores urine until it is eliminated from the body. As the bladder fills with urine, its walls stretch, and the pressure inside the bladder increases.
2. Sensory input to the spinal cord: The stretch receptors in the bladder walls send signals to the spinal cord, indicating that the bladder is full.
3. Activation of the micturition reflex: The spinal cord processes the sensory input and generates a reflex response that activates the muscles of the bladder and urethral sphincters.
4. Contraction of the bladder muscles: The muscles of the bladder wall contract, forcing urine out of the bladder and into the urethra.
5. Relaxation of the urethral sphincters: The urethral sphincters, which are circular muscles that control the flow of urine through the urethra, relax, allowing urine to pass out of the body.
Therefore, during micturition, the muscles of the urinary bladder will contract, and the urethral sphincters will relax to allow the flow of urine out of the body.
The glandular tissue of each breast is divided into 15-20_____.- a)Mammary lobes
- b)Ampulla
- c)Lactiferous duct
- d)Mammary duct
Correct answer is option 'A'. Can you explain this answer?
The glandular tissue of each breast is divided into 15-20_____.
a)
Mammary lobes
b)
Ampulla
c)
Lactiferous duct
d)
Mammary duct
|
|
Suresh Iyer answered |
The glandular tissue of each breast is divided into 15-20 mammary lobes which contain cluster of alveoli. Cells of alveoli secretes milk.
Finger-like projections appear on the trophoblast after implantation is called?- a)Hausturia
- b)Chorionic villi
- c)Chorionic gonadotropin
- d)Placenta
Correct answer is option 'B'. Can you explain this answer?
Finger-like projections appear on the trophoblast after implantation is called?
a)
Hausturia
b)
Chorionic villi
c)
Chorionic gonadotropin
d)
Placenta
|
|
Ram Mohan answered |
Option B is correct becoz chorionic villi appears on the tropoblast after the implantation
Corpus luteum is- a)Outer part of the brain
- b)Tissue joining two cerebral hemispheres
- c)Remnant of the follicle in the ovary
- d)Tissue in testes to produce testosterone E Inner part of the brain
Correct answer is option 'C'. Can you explain this answer?
Corpus luteum is
a)
Outer part of the brain
b)
Tissue joining two cerebral hemispheres
c)
Remnant of the follicle in the ovary
d)
Tissue in testes to produce testosterone E Inner part of the brain
|
|
Lonely answered |
The corpus luteum (plural: corpora lutea) is a temporary endocrine structure involved in ovulation and early pregnancy. ... The remnants of the follicle after ovulation is referred to as the corpus luteum and ranges from 2-5 cm in diameter but involutes as it matures.
The body of sperm is covered by _______- a)Cell membrane
- b)Head
- c)Cell wall
- d)Cytoplasm
Correct answer is option 'A'. Can you explain this answer?
The body of sperm is covered by _______
a)
Cell membrane
b)
Head
c)
Cell wall
d)
Cytoplasm
|
Imk Pathsala answered |
As in the case of any other cell, sperms are enveloped by a phospholipid bilayer, which is also called as plasma membrane or cell membrane.
Which of the following hormones are secreted by the placenta?
A. Human chorionic gonadotropin
B. Chorionic thyrotropin
C. Estrogen
D. Progesterone- a)A only
- b)A & B
- c)A, B & C
- d)A, B, C & D
Correct answer is option 'D'. Can you explain this answer?
A. Human chorionic gonadotropin
B. Chorionic thyrotropin
C. Estrogen
D. Progesterone
a)
A only
b)
A & B
c)
A, B & C
d)
A, B, C & D
|
|
Krithika Sharma answered |
Introduction
The placenta plays a crucial role in pregnancy by producing various hormones that support fetal development and maintain the pregnancy. The hormones secreted by the placenta include:
1. Human Chorionic Gonadotropin (hCG)
- hCG is one of the first hormones produced by the placenta.
- It helps maintain the corpus luteum, which in turn produces progesterone during early pregnancy.
- hCG is also the hormone detected in pregnancy tests.
2. Chorionic Thyrotropin
- Chorionic thyrotropin, also known as human chorionic thyrotropin (hCT), is involved in stimulating the thyroid gland.
- It helps increase the production of thyroid hormones, which are essential for the metabolism and development of both the mother and the fetus.
3. Estrogen
- The placenta produces significant amounts of estrogen, particularly estriol.
- Estrogen plays a vital role in the growth and development of the uterus and breast tissues.
- It also helps regulate other hormones and supports fetal development.
4. Progesterone
- Progesterone is another critical hormone secreted by the placenta.
- It maintains the uterine lining, allowing for implantation and growth of the embryo.
- Progesterone also helps suppress maternal immune responses to prevent rejection of the fetus.
Conclusion
In conclusion, the placenta secretes all four hormones: Human Chorionic Gonadotropin, Chorionic Thyrotropin, Estrogen, and Progesterone. Each of these hormones plays a significant role in ensuring a healthy pregnancy and supporting fetal growth, making option 'D' the correct answer.
The placenta plays a crucial role in pregnancy by producing various hormones that support fetal development and maintain the pregnancy. The hormones secreted by the placenta include:
1. Human Chorionic Gonadotropin (hCG)
- hCG is one of the first hormones produced by the placenta.
- It helps maintain the corpus luteum, which in turn produces progesterone during early pregnancy.
- hCG is also the hormone detected in pregnancy tests.
2. Chorionic Thyrotropin
- Chorionic thyrotropin, also known as human chorionic thyrotropin (hCT), is involved in stimulating the thyroid gland.
- It helps increase the production of thyroid hormones, which are essential for the metabolism and development of both the mother and the fetus.
3. Estrogen
- The placenta produces significant amounts of estrogen, particularly estriol.
- Estrogen plays a vital role in the growth and development of the uterus and breast tissues.
- It also helps regulate other hormones and supports fetal development.
4. Progesterone
- Progesterone is another critical hormone secreted by the placenta.
- It maintains the uterine lining, allowing for implantation and growth of the embryo.
- Progesterone also helps suppress maternal immune responses to prevent rejection of the fetus.
Conclusion
In conclusion, the placenta secretes all four hormones: Human Chorionic Gonadotropin, Chorionic Thyrotropin, Estrogen, and Progesterone. Each of these hormones plays a significant role in ensuring a healthy pregnancy and supporting fetal growth, making option 'D' the correct answer.
What happen during fertilisation after all the sperm reach close to ovum?- a)All sperms except one lose their tails.
- b)Only two sperm nearest to ovum penetrate zona pellucida
- c)Cells of corona radiate trap all the sperms except one
- d)Secretion of acrosome helps one sperm enter cytoplasm of ovum
Correct answer is option 'D'. Can you explain this answer?
What happen during fertilisation after all the sperm reach close to ovum?
a)
All sperms except one lose their tails.
b)
Only two sperm nearest to ovum penetrate zona pellucida
c)
Cells of corona radiate trap all the sperms except one
d)
Secretion of acrosome helps one sperm enter cytoplasm of ovum
|
|
Rhea Sarkar answered |
Millions of sperms are released during insemination that reaches to ovum for fertilisation. Only one sperm enter the ovum by penetrating the zona pellucida layer of ovum using the enzyme present in its acrosome.
The number of egg cells produced as a result of meiosis in humans is- a)1
- b)2
- c)3
- d)4
Correct answer is option 'A'. Can you explain this answer?
The number of egg cells produced as a result of meiosis in humans is
a)
1
b)
2
c)
3
d)
4
|
|
Hitakshi Tamta answered |
Primary oocyte undergoes first meiotic division to produce one secondary oocyte (egg cell) and first polar body (nonfunctional cell). Secondary oocyte completes meiosis II and produces one functional ovum and second polar body. First and second polar bodies are nonfunctional cells; so, oogenesis produce one functional egg cell in each round. Thus, the correct answer is 'A'.
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