Class 10 Science Chapter 7 Question Answers - How Do Organisms Reproduce

Q1: What is reproduction?  
Ans: Reproduction is the process by which an organism produces its young ones for the perpetuation of its race.

Q2: Mention two modes of reproduction. 
Ans: The two modes of reproduction are sexual reproduction and asexual reproduction.

Q3: Give one example for each of the following.
(а) Plants in which vegetative propagation occurs by grafting.
(b) Plants in which vegetative propagation occurs by leaves.
Ans: (a) Rose, grapes can be vegetatively propagated by grafting.
(b) Bryophyllum can be vegetatively propagated by leaves.                                                                                  

  Grafting

Q4: Name a plant that has lost the capacity to produce seed. How can it reproduce?
Ans: Banana. It can reproduce by vegetative propagation.

Q5: Name any two consequences of unsafe sex.  
Ans: The two consequences of unsafe sex are:

• Transmission of sexually transmitted diseases
• Unwanted pregnancy

Q6: Name the hormone, the secretion of which is responsible for dramatic changes in appearance in girls when they approach 10-12 years of age.  
Ans: Oestrogen

Q7: Mention the modes of reproduction used by
(a) Amoeba
(b) Planaria  
Ans: (a) Amoeba – Binary fission
(b) Planaria – Regeneration

Q8: Name any two types of asexual reproduction.  
Ans: (a) Fission
(b) Budding

Q9: State the method used for growing rose plants.
Ans: Vegetative propagation

Q10: State which type of method is used for growing the Jasmine plant.  
Ans: Layering.

Layering 

Q11: Name the male and the female gametes in human beings. 
Ans: Male gamete: Sperm and Female gamete: Ovum.

Q12: Name the male and the female gametes in human beings. 
Ans: The fusion of two gametes is termed syngamy, marking the first stage in the fertilization process. 

Q13: What are the various methods of Vegetative propagation?    
Ans:

• Cutting
• Layering
• Grafting
• Parthenogenesis
• Micro-propagation in vitro 

Q14: Mention the reproductive parts of a flower.
Ans: Male reproductive part – Stamens.
           Female reproductive part – Pistil.

Q15: What is Pollination?
Ans: Pollination is the transfer of pollen grains from anther to stigma, occurring within the same or different flowers. 

PollinationQ16: Describe cross-pollination.
Ans: Cross-pollination refers to the transfer of pollen grains from the anther of one flower to the stigma of another flower within the same species.

Q17: Write the names of one male and female sex hormone.
Ans: Male sex hormone – testosterone.
           Female sex hormone – progesterone.

Q18: What is Ovulation?
Ans: Ovarian follicles mature, and one usually develops into a mature ovum. This ovum is released during ovulation, entering the fallopian tube. Ovulation generally occurs in one ovary at a time.

Q19: Define sexually transmitted disease and give two examples. 
Ans: Infectious diseases transmitted through sexual contact are known as STDs (Sexually Transmitted Diseases). Common symptoms include a burning sensation during urination and urethral discharge. Gonorrhea and Syphilis are two examples of such diseases, both of which are treatable.

Q20: Write the full forms of IUCD, AIDS, HIV, and OC.
Ans: IUCD – Intrauterine Contraceptive Devices
AIDS – Acquired Immuno-Deficiency Syndrome
HIV – Human Immuno Virus
OC – Oral Contraceptives.