Zoology 2024 Paper I 50 marks 150 words Compulsory Write short notes

Q1

Write short notes on the following in about 150 words each: (a) Concept and organization of Coelom (10 marks) (b) Metamorphosis in Insects (10 marks) (c) Thyroid gland and its functions (10 marks) (d) Hepatic Schizogony (10 marks) (e) Aquatic mammals and their adaptations (10 marks)

हिंदी में प्रश्न पढ़ें

निम्नलिखित में से प्रत्येक पर लगभग 150 शब्दों में संक्षिप्त टिप्पणियाँ लिखिए : (a) प्रगुहा की अवधारणा एवं संगठन (10 अंक) (b) कीटों में कायांतरण (10 अंक) (c) अवटु (थायरॉइड) ग्रंथि और इसके कार्य (10 अंक) (d) यकृतीय विखंडनजनन (10 अंक) (e) जलीय स्तनधारी और उनके अनुकूलन (10 अंक)

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Directive word: Write short notes

This question asks you to write short notes. The directive word signals the depth of analysis expected, the structure of your answer, and the weight of evidence you must bring.

See our UPSC directive words guide for a full breakdown of how to respond to each command word.

How this answer will be evaluated

Approach

The directive 'write short notes' demands concise, information-dense responses for each sub-part. Allocate approximately 30 words per mark, giving ~30 words/2 minutes per sub-part. Structure each note as: definition (20%) → key features/process (60%) → significance/example (20%). No introduction or conclusion across parts; treat each as standalone. Prioritize precision over elaboration.

Key points expected

(a) Coelom: Define coelom as mesoderm-lined body cavity; distinguish acoelomate, pseudocoelomate, and coelomate (eucoelomate) conditions with representative phyla; mention schizocoely vs enterocoely as modes of formation
(b) Metamorphosis: Define as abrupt structural reorganization; contrast holometabolous (complete: egg-larva-pupa-adult, e.g., Bombyx mori/Silkworm) and hemimetabolous (incomplete: egg-nymph-adult, e.g., Cockroach); mention hormonal control by PTTH, ecdysone, and juvenile hormone
(c) Thyroid: Identify follicular cells and colloid; list T3, T4, calcitonin secretion; state functions—BMR regulation, growth/development (cretinism/myxedema if deficient), calcium homeostasis; cite endemic goiter in Himalayan/sub-Himalayan regions due to iodine deficiency
(d) Hepatic schizogony: Define as asexual multiplication in liver; identify Plasmodium species (P. vivax, P. falciparum); describe cryptozoites → cryptomerozoites → metacryptozoites; distinguish from erythrocytic schizogony; mention pre-erythrocytic cycle duration (~8 days for P. vivax)
(e) Aquatic mammals: Identify Cetacea (whales, dolphins), Sirenia (dugongs), Pinnipedia (seals); list adaptations—streamlined body, blubber, blowhole, reduced limbs/flippers, countercurrent heat exchange, diving reflex; cite Ganges River Dolphin (Platanista gangetica) as Indian example

Evaluation rubric

Dimension	Weight	Max marks	Excellent	Average	Poor
Concept correctness	20%	10	All five sub-parts demonstrate accurate core definitions: coelom as mesoderm-lined (not any body cavity), metamorphosis types correctly distinguished by pupal stage presence/absence, thyroid hormones specified with correct targets, hepatic schizogony restricted to liver phase with correct terminology, aquatic mammals distinguished from marine reptiles/fish by mammalian traits	Definitions broadly correct but with minor errors: coelom confused with haemocoel, metamorphosis types conflated, thyroid functions listed without hormone specificity, hepatic schizogony conflated with erythrocytic phase, aquatic mammals listed without distinguishing mammalian characteristics	Fundamental misconceptions: coelom defined as any body cavity, metamorphosis described as 'growth' without structural reorganization, thyroid confused with parathyroid, hepatic schizogony applied to any asexual reproduction, aquatic mammals include penguins/fish
Diagram / labelling	20%	10	At least two clear, labeled diagrams: for (a) cross-section showing coelom layers (ectoderm-mesoderm-coelom-endoderm) comparing types; for (c) thyroid follicle structure with colloid, follicular cells, and parafollicular cells; OR for (d) life cycle diagram showing liver stage; labels precise and anatomically correct	One diagram attempted with partial labeling, OR two diagrams with significant errors: coelom diagram lacks germ layer distinction, thyroid diagram omits colloid or cell types, hepatic schizogony diagram conflated with full Plasmodium life cycle	No diagrams, OR diagrams present but fundamentally flawed: unlabeled, wrong orientation, or depicting unrelated structures (e.g., kidney for thyroid); scribbles without anatomical accuracy
Examples & nomenclature	20%	10	Specific, taxonomically correct examples for each applicable sub-part: (a) Ascaris (pseudocoelomate), Chordata (coelomate); (b) Bombyx mori/Silkworm (holometabolous), Periplaneta/Cockroach (hemimetabolous); (c) T3/T4/calcitonin named; (d) P. vivax, P. falciparum distinguished; (e) Platanista gangetica, Balaenoptera, Dugong dugon cited with correct families	Examples given but with taxonomic imprecision: 'earthworm' for coelomate without noting Annelida, 'butterfly' without genus/species, 'malaria parasite' without Plasmodium specification, generic 'whale/seal' without species or Indian relevance	No examples, OR incorrect examples: 'snake' for coelomate (actually vertebrate but misleading), 'frog' for metamorphosis (amphibian, not insect), 'insulin' for thyroid hormone, 'Amoeba' for hepatic schizogony, 'crocodile' for aquatic mammal
Process explanation	20%	10	Clear sequential processes where applicable: (a) schizocoely (mesoderm splits) vs enterocoely (archenteron pouches) with developmental outcomes; (b) hormonal cascade PTTH → prothoracic gland → ecdysone, modulated by JH; (d) sporozoite → cryptozoite → cryptomerozoite → metacryptozoite → merozoite release with timing; processes show cause-effect relationships	Processes mentioned but sequence unclear or incomplete: coelom formation stated without mechanisms, metamorphosis 'controlled by hormones' without cascade, hepatic schizogony as 'multiplication in liver' without stages, no mention of synchronous vs asynchronous schizogony	No process explanation, OR incorrect sequences: random hormone listing without PTTH initiation, hepatic schizogony described as sexual reproduction, metamorphosis attributed to 'environmental change' without endocrine control
Evolutionary / applied context	20%	10	Broader significance integrated: (a) coelom as key evolutionary innovation enabling organ complexity and hydrostatic skeleton; (b) adaptive significance of complete metamorphosis (resource partitioning, reduced competition); (c) public health relevance of IDD program, cretinism prevention; (d) relevance to malaria prophylaxis timing (primaquine targeting hypnozoites); (e) conservation status of Ganges Dolphin (endangered, habitat degradation)	Brief mention of significance without elaboration: coelom 'important for evolution', metamorphosis 'helps survival', thyroid 'essential for health', hepatic schizogony 'causes malaria', aquatic mammals 'need protection'—generic statements without specific application	No evolutionary or applied context, OR misapplied: coelom as 'digestive aid', metamorphosis as 'disadvantage', thyroid linked to diabetes, hepatic schizogony as 'beneficial to host', aquatic mammal adaptations as 'primitive traits'

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