Zoology
- Capacitation occurs in : Answer: 3. Female Reproductive tract Key idea: Freshly ejaculated sperm cannot fertilise an ovum yet. They must spend some time in the secre... 1
- Which cells of 'Crypts of Lieberkuhn' secrete antibacterial lysozyme ? Answer: 1. Paneth cells Key idea: The crypts of Lieberkuhn in the intestine hold several cell types. Paneth cells secrete lysozyme and defen... 1
- A decrease in blood pressure/volume will not cause the release of : Answer: 1. Atrial Natriuretic Factor Key idea: A fall in blood pressure or volume triggers hormones that raise it; ANF does the opposite. Lo... 1
- Smooth muscles are Answer: 4. involuntary, fusiform, non-striated Smooth muscles are involuntary, spindle-shaped (fusiform), uninucleate and non-striated. They... 1
- Which of the following is correct regarding AIDS causative agent HIV? Answer: 1. HIV is enveloped virus that contains two identical molecules of single-stranded RNA and two molecules of reverse transcriptase. H... 1
- Among the following edible fishes, which one is a marine fish having rich source of omega-3 fatty acids? Answer: 3. Mackerel Mackerel is a marine fish and a good source of omega-3 fatty acids. Mangur (catfish), Mrigala (a major carp) and Mystus... 1
- Which of the following sets of diseases is caused by bacteria? Answer: 4. Cholera and tetanus Cholera and tetanus are caused by bacteria (Vibrio cholerae and Clostridium tetani). Smallpox, mumps, herpes... 1
- Match Column—I with Column—II for housefly classification and select the correct option using the codes given below :Column—I: a. Family; b. Order; c. Class; d. PhylumColumn—II: (i) Diptera; (ii) Arthropoda; (iii) Muscidae; (iv) InsectaCodes :a b c d Answer: 4. (iii) (i) (iv) (ii) The housefly is classified as: Phylum Arthropoda (ii), Class Insecta (iv), Order Diptera (i), Family Muscidae... 1
- Choose the correct statement. Answer: 1. All cyclostomes do not possess jaws and paired fins. Cyclostomes (lampreys, hagfishes) have no jaws and no paired fins. Correct.... 1
- In male cockroaches, sperms are stored in which part of the reproductive system? Answer: 4. Seminal vesicles In a male cockroach, the testes make sperm, which pass through the vasa deferentia to the seminal vesicles, wher... 1
- Genetic drift operates in Answer: 4. small isolated population Genetic drift is a random change in allele frequency due to chance. Its effect is strong in small isola... 1
- In Hardy-Weinberg equation, the frequency of heterozygous individual is represented by Answer: 1. 2 pq The Hardy-Weinberg equation is p² + 2pq + q² = 1 . p² and q² are the homozygous genotypes, and 2pq is the frequency of heter... 1
- The chronological order of human evolution from early to the recent is Answer: 1. Ramapithecus → Australopithecus → Homo habilis → Homo erectus Use the approximate ages given in NCERT. Ramapithecus: about 15 mil... 1
- Which of the following is the correct sequence of events in the origin of life?I. Formation of protobiontsII. Synthesis of organic monomersIII. Synthesis of organic polymersIV. Formation of DNA-based genetic systems Answer: 2. II, III, I, IV The chemical evolution order is: Synthesis of organic monomers (II). Synthesis of organic polymers (III). Formatio... 1
- Which of the following depicts the correct pathway of transport of sperms? Answer: 4. Rete testis → Efferent ductules → Epididymis → Vas deferens The sperm path is: seminiferous tubules, then rete testis, then effer... 1
- Match Column—I with Column—II and select the correct option using the codes given below :Column—I: a. Mons pubis; b. Antrum; c. Trophectoderm; d. NebenkernColumn—II: (i) Embryo formation; (ii) Sperm; (iii) Female external genitalia; (iv) Graafian fol… Answer: 1. (iii) (iv) (i) (ii) Mons pubis: fatty cushion over the pubic bone, part of the female external genitalia (iii). Antrum: fluid-fil... 1
- Several hormones like hCG, hPL, estrogen, progesterone are produced by Answer: 1. placenta The placenta is a temporary endocrine tissue during pregnancy. It makes hCG, hPL (human placental lactogen), estrogens a... 1
- Name the blood cells, whose reduction in number can cause clotting disorder, leading to excessive loss of blood from the body. Answer: 3. Thrombocytes Thrombocytes (platelets) release clotting factors and form the platelet plug at an injury. A fall in their number (t... 1
- Serum differs from blood in Answer: 2. lacking clotting factors Serum is plasma without the clotting factors (fibrinogen and others), or in other words the fluid left a... 1
- The partial pressure of oxygen in the alveoli of the lungs is Answer: 1. more than that in the blood Gases move from higher to lower partial pressure (pO₂). Alveolar pO₂ is about 104 mm Hg, while deoxyg... 1
- Lungs do not collapse between breaths and some air always remains in the lungs which can never be expelled because Answer: 1. there is a negative intrapleural pressure pulling at the lung walls The pleural cavity around each lung has a pressure lower than... 1
- Which hormones do stimulate the production of pancreatic juice and bicarbonate? Answer: 2. Cholecystokinin and secretin Hormones of the gut control pancreatic secretion. Secretin acts on pancreatic acinar cells to releas... 1
- Name a peptide hormone which acts mainly on hepatocytes, adipocytes and enhances cellular glucose uptake and utilization. Answer: 4. Insulin Insulin is a peptide hormone from the beta cells of the pancreas. It acts mainly on hepatocytes and adipocytes (and muscl... 1
- The posterior pituitary gland is not a 'true' endocrine gland because Answer: 1. it only stores and releases hormones The posterior pituitary (neurohypophysis) does not make its own hormones. Oxytocin and vasop... 1