NEET Previous Year Questions (2016-2024): Structural Organisation in Animals | Biology Class 11 PDF Download

2024

Q1: In both sexes of cockroach, a pair of jointed filamentous structures called anal cerci are present on       (NEET 2024)
(a) 5th segment
(b) 10th segment
(c) 8th and 9th segment
(d) 11th segment
Ans: (b)
The correct answer is Option B.
Anal cerci in both male and female cockroaches are located at the base of the 10th  abdominal segment of their bodies. The cerci are a pair of long, filamentous, sensory appendages that help cockroaches detect movements in the air, which warns them of approaching threats from behind, such as predators. This placement provides an effective mechanism for detecting environmental changes directly around the cockroach's posterior, enhancing their ability to quickly respond and escape threats. The location on the 10th segment is typical and consistent in all cockroaches across different species.

Q2: Match List I with List II:

Choose the correct answer from the options given below:
(a) A-II, B-I, C-III, D-IV
(b) A-IV, B-III, C-I, D-II
(c) A-III, B-IV, C-I, D-II
(d) A-II, B-I, C-IV, D-III
Ans: (c)
To match List I (types of epithelium) with List II (examples where these epithelia are found), we need to understand the characteristics and common locations of each type of epithelial tissue.

Here's the clarification for each match:

Unicellular glandular epithelium: This refers to single cells that function as glands, such as goblet cells. They are typically found in epithelial linings where they secrete mucus; within the digestive tract, goblet cells are common components.

Compound epithelium: This type is characterized by multiple layers of cells and is primarily protective. Common examples include skin and the inner lining of the mouth which needs protection against mechanical and chemical stress.

Multicellular glandular epithelium: This is found in glands composed of many cells. Examples include the salivary glands, pancreas, etc., where multiple cells work together to produce and secrete substances like enzymes and saliva.

Endocrine glandular epithelium: These glands are ductless and release hormones directly into the blood. An example of such a gland is the pancreas, which not only acts as an exocrine gland by producing digestive enzymes but also functions endocrinologically by regulating blood sugar levels through insulin and glucagon production.

Based on the above understanding:

• A (Unicellular glandular epithelium) matches with III (Goblet cells of alimentary canal).
• B (Compound epithelium) matches with IV (Moist surface of buccal cavity).
• C (Multicellular glandular epithelium) matches with I (Salivary glands).
• D (Endocrine glandular epithelium) matches with II (Pancreas).

Thus, the correct answer is Option C: A-III, B-IV, C-I, D-II

Q3: Match List I with List II related to digestive system of cockroach.

Choose the correct answer from the options given below:
(a) A-IV, B-II, C-III, D-I
(b) A-I, B-II, C-III, D-IV
(c) A-IV, B-III, C-II, D-I
(d) A-III, B-II, C-IV, D-I
Ans: (a)
The digestive system of a cockroach consists of several specialized structures that perform specific functions:
Crop is a part of the alimentary canal where food is stored temporarily. This aligns with the description for List I "A. The structures used for storing of food". Thus, A corresponds to IV (Crop).
Gastric Caeca are blind tubules located at the junction of the foregut and the midgut in insects. These tubules secrete enzymes and provide an increased surface area for digestion and absorption. This fits the description for List I "B. Ring of 6-8 blind tubules at junction of foregut and midgut". Hence, B corresponds to II (Gastric Caeca).
Malpighian tubules are thin filamentous structures present at the junction of the midgut and hindgut. They are primarily involved in excretion and osmoregulation. They match the description for List I "C. Ring of 100-150 yellow coloured thin filaments at junction of midgut and hindgut". Thus, C corresponds to III (Malpighian tubules).
Gizzard, also known as the proventriculus, is equipped with hard chitinous plates that grind the food mechanically. This description fits List I "D. The structures used for grinding the food". Therefore, D corresponds to I (Gizzard).
By collaborating all this information, the correct answer is: Option A: A-IV, B-II, C-III, D-I

2023

Q1: Given below are two statements:     (NEET 2023)
Statement I: Ligaments are dense irregular tissue.
Statement II: Cartilage is dense regular tissue.
In the light of the above statements, choose the correct answer from the options given below:
(a) Both Statement I and Statement II are true  
(b) Both Statement I and Statement II are false
(c) Statement I true and Statement II false      
(d) Statement I false Statement II are true
Ans: (b)

• Ligaments are a type of dense regular connective tissue, not irregular. They connect bones to other bones, providing stability and support.
• On the other hand, cartilage is a type of specialized connective tissue that is not classified as dense. It's composed of cells called chondrocytes which are embedded in a matrix of collagen and elastic fibers. It's neither dense regular nor dense irregular tissue.

Therefore, both statements I and II are incorrect.

Q2: In cockroach, excretion is brought about by-      (NEET 2023)
A. Phallic gland
B. Urecose gland
C. Nephrocytes
D. Fat body
E. Collaterial glands
Choose the correct answer from the options given below :
(a) A and E only
(b) A, B and E only
(c) B, C and D only
(d) B and D only
Ans: (c)

• In cockroaches, excretion is primarily accomplished by Malpighian tubules, which are not listed in the provided options. However, among the provided options, urecose glands, nephrocytes, and the fat body do participate in excretory processes to some degree.
• Urecose glands are present in male cockroach of some species. They synthesise uric acid. Nephrocytes are large, colourless, ovoid, binucleate cells attached to the dorsal diaphragm in the body cavity. Fat body accumulates, produces and stores uric acid.
• Phallic gland is the structure of male reproductive system of cockroach and it secretes the outer layer of spermatophore. Collaterial gland is the structure of female reproductive system of cockroach and it secretes the hard egg-case or ootheca around fertilised eggs.

Q3: Match List I with List II.     (NEET 2023)

Choose the correct answer from the options given below:
(a) A-I, B-II, C-IV, D-III
(b) A-II, B-III, C-I, D-IV
(c) A-II, B-I, C-IV, D-III
(d) A-III, B-IV, C-II, D-I
Ans: (c)

• Mast cells (A) : These are a type of white blood cell that is part of the immune system. They are found in many tissues, but particularly in areas close to the external environment, such as the skin and mucous membranes. They are found in connective tissues like areolar tissue
• Inner surface of bronchiole (B) : The bronchioles are small airways in the respiratory tract that lead to the alveoli (tiny air sacs in the lungs). The inner surface of bronchioles is lined with ciliated epithelium. Cilia are small, hair-like structures that help move mucus and trapped particles out of the lungs.
• Blood (C) : This is a specialized type of connective tissue. It has cells (red and white blood cells, and platelets) suspended in a liquid matrix called plasma.
• Tubular parts of nephron (D) : Nephrons are the functional units of the kidney, responsible for filtering blood and creating urine. The tubular parts of the nephron are lined with cuboidal epithelium. This type of epithelial tissue has cells that are roughly as tall as they are wide.

Given this information, the correct match seems to be :
Option B :A-I I, B-I, C-IV, D-III

Q4: Which of the following is characteristic feature of cockroach regarding sexual dimorphism?      (NEET 2023)
(a) Dark brown body colour and anal cerci
(b) Presence of anal styles
(c) Presence of sclerites
(d) Presence of anal cerci
Ans: (b)

• Option (b) is the correct answer because anal styles are present in male cockroaches and absent in female cockroaches.
• Option (a), (c) and (d) are not the correct answers because sclerites, anal cerci and dark brown body colour are common features of both male and female cockroaches.

2022

Q1: In which of the following animals, digestive tract has additional chambers like crop and gizzard?    (NEET 2022 Phase 1)
(a) Corvus, Columba, Chameleon
(b) Bufo, Balaenoptera, Bangarus
(c) Catla, Columba, Crocodilus
(d) Pavo, Psittacula, Corvus
Ans: (d)

• Option (d) is the correct answer because two additional chambers like crop and gizzard in alimentary canal are present in birds.
• Pavo (Peacock), Psittacula (Parrot), Corvus (Crow) and Columba (Pigeon) are birds.
• Option (a), (b) and (c) are incorrect because Catla is a bony fish, Crocodilus, Chameleon and Bangarus are reptiles, Bufo is an amphibian and Balaenoptera is an aquatic mammal.

Q2: Which of the following is not a connective tissue?    (NEET 2022 Phase 1)
(a) Adipose tissue
(b) Cartilage
(c) Blood
(d) Neuroglia
Ans: (c)
Option (d) is the correct answer as neuroglia are a part of nervous tissue.

• Neuroglia are the supportive cells of nervous tissue. They make up more than half the volume of neural tissue. Neurons, the unit of neural system are excitable cells.
• Cartilage and blood are specialised type of connective tissues.
• Adipose tissue is a type of loose connective tissue.

Q3: Tegmina in cockroach, arises from:     (NEET 2022 Phase 1)
(a) Metathorax
(b) Mesothorax
(c) Prothorax and Mesothorax
(d) Prothorax
Ans: (b)

• Option (b) is the correct answer because tegmina or forewings (the first pair of wings) in cockroach arises from mesothorax.
• Options (a), (c) and (d) are incorrect because no wing arises from prothorax and hindwings arise from metathorax.

Q4: Match List - I with List - II     (NEET 2022 Phase 1)

Choose the correct answer from the options given below:

(a) (a)-(iv), (b)-(iii), (c)-(i), (d)-(ii)
(b) (a)-(i), (b)-(ii), (c)-(iii), (d)-(iv)
(c) (a)-(ii), (b)-(i), (c)-(iv), (d)-(iii)
(d) (a)-(iii), (b)-(iv), (c)-(ii), (d)-(i)
Ans: (a)
Option (a) is the correct answer because

• Ciliated epithelium is mainly present in the inner surface of hollow organs like bronchioles and fallopian tubes. The function is to move particles or mucus in a specific direction over the epithelium.
• Some of the columnar or cuboidal cells get specialised for secretion and are called glandular epithelium. Goblet cells are unicellular glands.
• Tendons are dense regular connective tissues. They attach skeletal muscles to bones.
• Adipose tissue is a type of loose connective tissue located mainly beneath the skin. The cells of this tissue are specialised to store fats.

Q5: Which of the following types of epithelium is present in the bronchioles and Fallopian tubes?     (NEET 2022 Phase 2)
(a) Stratified squamous epithelium
(b) Simple squamous epithelium
(c) Simple columnar epithelium
(d) Ciliated epithelium
Ans: (d)

• Option (4) is the correct answer as ciliated epithelium is mainly present in the inner lining of hollow organs like bronchioles and fallopian tubes.
• Option (1) is incorrect as stratified squamous epithelium covers moist surfaces such as those of buccal cavity, pharynx and oesophagus.
• Option (2) is incorrect as simple squamous epithelium is found in the walls of blood vessels and air sacs of lungs.
• Option (3) is incorrect as simple columnar epithelium is found in the lining of stomach and intestine.

Q6: Match List-I with List-II regarding the organs of Cockroach:    (NEET 2022 Phase 2)

Choose the correct answer from the options given below :
(a) (a) - (i), (b) - (iv), (c) - (iii), (d) - (ii)
(b) (a) - (iv), (b) - (i), (c) - (ii), (d) - (iii)
(c) (a) - (iii), (b) - (ii), (c) - (i), (d) - (iv)
(d) (a) - (ii), (b) - (iv), (c) - (i), (d) - (iii)
Ans: (b)
Option (b) is the correct answer because
(a) Crop – Responsible for storage of food
(b) Proventriculus – Grinding the food particles
(c) Hepatic caecae – Secretion of digestive juice
(d) Malpighian tubules – Removal of nitrogenous waste

Q7: Choose the correct statements:   (NEET 2022 Phase 2)
(a) Bones support and protect softer tissues and organs
(b) Weight bearing function is served by limb bones
(c) Ligament is the site of production of blood cells.
(d) Adipose tissue is specialised to store fats.
(e) Tendons attach one bone to another.
Choose the most appropriate answer from the options given below:
(a) (a), (b) and (e) only
(b) (a), (b) and (d) only
(c) (b), (c) and (e) only
(d) (a), (c) and (d) only
Ans: (b)
Option (b) is the correct answer because statements (a), (b) and (d) are correct.

• Bones are the hardest tissue of our body that support and protect softer tissues and orgAns:
• Limb bones serve weight bearing function.
• Adipose tissue is a type of loose connective tissue specialised to store fats.
• Option (a) is incorrect because statement (e) is false as tendons attach bones to muscles.
• Option (c) is incorrect because statement (c) is false as bone marrow in some bones is the site of production of blood cells.
• Option (d) is incorrect because this option includes statement (c) which is false.

Q8: Excretion in cockroach is performed by all, EXCEPT:          (NEET 2022 Phase 2)
(a) Hepatic caeca
(b) Urecose glands
(c) Malpighian tubules
(d) Fat body
Ans: (a)
Option (a) is correct answer because hepatic caeca are responsible for secretion of digestive juices in cockroach and it does not participate in excretion. Urecose glands in male cockroach, Malpighian tubules and fat bodies in both male and female cockroach are considered as excretory structures.

2021

Q1: Which one of the following characteristic is incorrect with respect to cockroach?    (NEET 2021)
(a) In females, 7^th - 9^th sterna together form a genital pouch.
(b) 10^th abdominal segment in both sexes, bears a pair of anal cerci.
(c) A ring of gastric caeca is present at the junction of midgut and hind gut.
(d) Hypopharynx lies within the cavity enclosed by the mouth parts.
Ans: (c)
Option (c) is incorrect because a ring of gastric caecae is present at the junction of foregut and midgut. At the junction of midgut and hindgut, malpighian tubules are present.

• Hypopharynx lies within the cavity enclosed by mouthparts.
• In female cockroach, the 7th sternum is boat shaped and together with the 8th and 9th sterna forms a genital pouch.
• 10th abdominal segment in both sexes, bears a pair of anal cerci and 9th sternum only in male cockroach, bears a pair of chitinous anal style.

Q2: Which of the following statements wrongly represents the nature of smooth muscle?    (NEET 2021)
(a) Communication among the cells is performed by intercalated discs
(b) These muscles are present in the wall of blood vessels
(c) These muscle have no striations
(d) They are involuntary muscles
Ans: (a)

• Option (a) is incorrect because intercalated discs are found only in cardiac muscle tissue.
• Smooth muscle fibres are non-striated and involuntary in nature and are present in the wall of blood vessels, uterus, gall bladder, alimentary canal etc.

Q3: Following are the statements about prostomium of earthworm.    (NEET 2021)
(a) It serves as a covering for mouth.
(b) It helps to open cracks in the soil into which it can crawl.
(c) It is one of the sensory structures.
(d) It is the first body segment.
Choose the correct answer from the options given below.
(a) (a), (b), (c) and (d) are correct
(b) (b) and (c) are correct
(c) (a), (b) and (c) are correct
(d) (a), (b) and (d) are correct
Ans: (c)
The anterior end of the earthworm has mouth which has covering called prostomium.

• Prostomium acts as a wedge to force open cracks in the soil.
• Prostomium has receptors, so it is sensory in function.
• The first body segment of earthworm is the peristomium.

Q4: Identify the types of cell junctions that help to stop the leakage of the substances across a tissue and facilitation of communication with neighbouring cells via rapid transfer of ions and molecules.                 (NEET 2021)
(a) Adhering junctions and Tight junctions, respectively.
(b) Adhering junctions and Gap junctions, respectively.
(c) Gap junctions and Adhering junctions, respectively.
(d) Tight junctions and Gap junctions, respectively.
Ans: (d)
Three types of junctions are found in tissues

• Tight junctions stop leakage of substances from leaking across a tissue.
• Adhering junctions cement and keep neighbouring cells together.
• Gap junctions or communication junctions facilitate communication between cells by connecting the cytoplasm of adjoining cells.

2020

Q1: Cuboidal epithelium with brush border of microvilli is found in:     (NEET 2020)
(a) proximal convoluted tubule of nephron
(b) eustachian tube
(c) lining of intestine
(d) ducts of salivary glands
Ans: (a) 
Cuboidal epithelium with brush border of microvilli is found in proximal convoluted tubule of nephron (PCT).

2019

Q1: The ciliated epithelial cells arc required to move particles or mucus in a specific direction. In humans, these cells are mainly present in    (NEET 2019)
(a) Bronchioles and fallopian tubes
(b) Bile duct and bronchioles
(c) Fallopian tubes and pancreatic duct
(d) Eustachian tube and salivary duct.
Ans: (a)
Bronchioles are lined by ciliated epithelium and fallopian tube.

Q2: Select the correct sequence of organs in the alimentary canal of cockroach starting from mouth.    (NEET 2019)
(a) Pharynx → Oesophagus → Ileum → Crop → Gizzard Colon → Rectum
(b) Pharynx → Oesophagus → Crop → Gizzard → Ileum → Colon → Rectum
(c) Pharynx → Oesophagus → Gizzard → Crop → Ileum → Colon → Rectum
(d) Pharynx → Oesophagus → Gizzard → Ileum → Crop → Colon → Rectum
Ans: (b)
In cockroach the food goes into
Mouth → Pharynx → Oesophagus → Crop → Gizzard → Ileum → Colon → Rectum → Anus 

Q3: Which of the statements given below is not true about formation of Annual Rings in trees?   (NEET 2019)
(a) Activity of cambium depends upon variation in climate.
(b) Annula ring are not prominent in trees of temperate region.
(c) Annula ring is a combination of spring wood and autumn wood produced in a year.
(d) Differential activity of cambium causes light and dark bands of tissue-early and late wood respectively
Ans: (b)
Annual rings are prominent only in tress of temperate region. In temperate regions climatic conditions are not uniform throughout the year. So, there is no differential activity of cambium. However in tropics climatic conditions are uniform throughout the year.

2018

Q1: Which of the following features is used to identify a male cockroach from a female cockroach?    (NEET 2018)
(a) Presence of a boat-shaped sternum on the 9^th abdominal segment.
(b) Presence of caudal styles
(c) Forewings with darker tegmina
(d) Presence of anal cerci
Ans: (b)
Male cockroach bears a pair of short threadlike anal/caudal styles which are absent in females. They project backwardly from the sides of 9^th abdominal segment in male cockroach.

2017

Q1: Select the correct route for the passage of sperms in male frogs.    (NEET 2017)
(a) Testes → Vasa of Terentia → Kidney → Seminal vesicle → Urinogenital duct → Cloaca
(b) Testes → Vasa of Terentia → Bidder’s canal → Ureter → Cloaca
(c) Testes → Vasa of Terentia → Kidney → Bidder’s canal → Urinogenital duct → Cloaca
(d) Testes → Bidder’s canal → Kidney → Vasa efferentia → Urinogenital duct → Cloaca
Ans: (c)
The correct route for transport of sperms in male frog is
Testes → Vasa efferentia → Kidney → Bidder’s canal → Urinogenital duct → Cloaca.

Q2: Frog’s heart when taken out of the body continues to beat for some time.
Select the best option from the following statements.    (NEET 2017)
(1) Frog is a poikilotherm.
(2) Frog does not have any coronary circulation.
(3) Heart is “myogenic” in nature.
(4) Fleart is autoexcitable.
(a) Only (4)
(b) (1) and (2)
(c) (3) and (4)
(d) Only (3)
Ans: (c)
The vertebrates process myogenic heart which is self contractile system or autoexcitable; it will thus keep working outside the body for some time.

2016

Q1: In male cockroaches, sperms are stored in which part of the reproductive system?    (NEET 2016 Phase 2)
(a) Seminal vesicles
(b) Mushroom glands
(c) Testes
(d) Vas deferens
Ans: (a)
Seminal vesicles are numerous small sacs present on ventral surface of anterior part of the ejaculatory duct which store sperms.

Q2: Smooth muscles are    (NEET 2016 Phase 2)
(a) Involuntary, Fusiform, Non-striated
(b) Voluntary, Multinucleate, Cylindrical
(c) Involuntary, Cylindrical, Striated
(d) Voluntary, Spindle-shaped, Uninucleate.
Ans: (a)
Smooth muscle fibres are elongated and spindle shaped (fusiform). Each fibre contains a single oval nucleus surrounded by cytoplasm (sareoplasm). In eytoplasm, myofibrils are arranged longitudinally. These fibres lack striations and sarcolemma. However, are enclosed by plasma membrane.

Q3: Which type of tissue correctly matches with its location?    (NEET 2016 Phase 1)

Ans: (c)
Wall of intestine is made of smooth muscle. Tendons consist of dense regular connective tissue fascicles encased in dense irregular connective tissue sheaths. Tip of nose consists of squamous epithelium. Lining of epithelium is made of columnar epithelium.

Q4: Which of the following features is not present in Periplaneta americana?    (NEET 2016 Phase 1)
(a) Exoskeleton composed of N-acetylglucos- amine
(b) Metamcrically segmented body
(c) Schizocoelom as body cavity
(d) Indeterminate and radial cleavage during embryonic development
Ans: (d)
Periplanata americana shows spiral and determinate types of cleavage during embryonic development which is a feature of Protostomes.