Zoology Practical Question Paper 2019 with Answers

Practical knowledge in zoology is essential to understanding the biological processes of animals. The 2019 question paper reflects diverse aspects, ranging from anatomy to physiology. This guide provides important questions and detailed answers to help students prepare effectively for exams and enhance their understanding of zoology concepts.

Anatomy and Morphology

Question: What is the difference between exoskeleton and endoskeleton?

Answer: Exoskeleton refers to the external skeletal structure found in organisms like insects, while endoskeleton refers to the internal skeleton found in vertebrates like humans.

Question: What are the major functions of bones in vertebrates?

Answer: Bones provide structural support, protection to vital organs, facilitate movement, store minerals, and house bone marrow for blood cell production.

Question: Describe the structure of a typical mammalian heart.

Answer: The mammalian heart is four-chambered, consisting of two atria and two ventricles. It is enclosed in a pericardial sac and functions to pump oxygenated and deoxygenated blood.

Question: What are the distinguishing features of a frog’s digestive system?

Answer: A frog’s digestive system consists of a mouth, pharynx, esophagus, stomach, small intestine, large intestine, cloaca, and liver. Frogs use both tongue and teeth for food capture and digestion.

Question: How do earthworms breathe?

Answer: Earthworms breathe through their moist skin by diffusion, allowing oxygen to pass into their blood and carbon dioxide to exit.

Question: Explain the significance of the vertebral column in vertebrates.

Answer: The vertebral column provides structural support, protects the spinal cord, and facilitates movement by serving as an attachment point for muscles.

Question: What is the function of the notochord in chordates?

Answer: The notochord provides structural support and serves as a precursor to the vertebral column in higher chordates.

Question: Differentiate between arteries and veins.

Answer: Arteries carry oxygenated blood away from the heart to the body, except for pulmonary arteries, while veins carry deoxygenated blood back to the heart, except for pulmonary veins.

Question: Describe the structure and function of the nephron in the kidney.

Answer: The nephron is the functional unit of the kidney, consisting of the glomerulus, Bowman’s capsule, proximal tubule, loop of Henle, distal tubule, and collecting duct, functioning in blood filtration and urine formation.

Question: What is the role of hemoglobin in the blood?

Answer: Hemoglobin in red blood cells binds to oxygen in the lungs and transports it to tissues, while also carrying carbon dioxide back to the lungs for exhalation.

Embryology and Development

Question: What is cleavage in embryonic development?

Answer: Cleavage is the rapid mitotic division of a fertilized egg (zygote) that leads to the formation of a multicellular embryo.

Question: Differentiate between holoblastic and meroblastic cleavage.

Answer: Holoblastic cleavage divides the entire egg into cells, as seen in mammals, while meroblastic cleavage partially divides the egg, seen in birds and reptiles.

Question: What is gastrulation, and why is it important?

Answer: Gastrulation is the process during embryonic development where the blastula reorganizes into a gastrula, forming the three germ layers: ectoderm, mesoderm, and endoderm.

Question: What are the primary functions of the placenta in mammals?

Answer: The placenta facilitates nutrient and oxygen transfer from the mother to the fetus, removes fetal waste, and produces hormones to support pregnancy.

Question: Define organogenesis.

Answer: Organogenesis is the process of organ formation during embryonic development, following gastrulation and differentiation of germ layers.

Question: Explain the role of yolk in animal development.

Answer: Yolk provides the essential nutrients required for the growth and development of the embryo, especially in oviparous animals.

Question: What is the difference between external and internal fertilization?

Answer: External fertilization occurs outside the body, common in aquatic animals, while internal fertilization takes place inside the body, typical in terrestrial animals.

Question: What is the function of the amniotic sac in reptiles, birds, and mammals?

Answer: The amniotic sac protects the developing embryo, provides a cushion against shocks, and maintains a stable environment for development.

Question: What is metamorphosis? Give an example.

Answer: Metamorphosis is the developmental process involving significant morphological changes from larva to adult, e.g., caterpillar transforming into a butterfly.

Question: What are stem cells, and why are they important?

Answer: Stem cells are undifferentiated cells capable of developing into various specialized cells. They play a crucial role in growth, repair, and medical research.

Physiology and Biochemistry

Question: What is homeostasis?

Answer: Homeostasis refers to the maintenance of a stable internal environment within an organism despite external environmental changes.

Question: What are enzymes, and how do they function?

Answer: Enzymes are biological catalysts that speed up chemical reactions in cells by lowering the activation energy required.

Question: What is the role of ATP in cellular processes?

Answer: ATP (adenosine triphosphate) serves as the primary energy currency of cells, providing energy for metabolic activities.

Question: Differentiate between aerobic and anaerobic respiration.

Answer: Aerobic respiration requires oxygen to produce energy, yielding carbon dioxide and water, while anaerobic respiration occurs without oxygen, producing less energy and byproducts like lactic acid.

Question: How do hormones regulate body functions?

Answer: Hormones act as chemical messengers, regulating growth, metabolism, reproduction, and other physiological processes by binding to target cells.

Question: What is the function of the liver in metabolism?

Answer: The liver regulates glucose levels, metabolizes fats and proteins, detoxifies harmful substances, and produces bile for digestion.

Question: Explain the process of osmoregulation in fishes.

Answer: Osmoregulation in fishes maintains water and salt balance, with freshwater fishes excreting dilute urine and marine fishes excreting concentrated urine.

Question: What is the role of the hypothalamus in the human body?

Answer: The hypothalamus regulates body temperature, hunger, thirst, emotions, and the endocrine system via the pituitary gland.

Question: What are the primary differences between prokaryotic and eukaryotic cells?

Answer: Prokaryotic cells lack a nucleus and membrane-bound organelles, while eukaryotic cells have both.

Question: Define photosynthesis and its significance.

Answer: Photosynthesis is the process by which plants convert light energy, water, and carbon dioxide into glucose and oxygen, serving as the foundation of the food chain.

The questions and answers listed above provide a comprehensive overview of key zoology concepts, helping students understand practical aspects of the subject better. By focusing on real-world examples and biological processes, this guide serves as a valuable educational resource.