Are you searching for Kerala Plus One Zoology previous year question papers and answers in PDF format from HSSlive? You’ve come to the right place! As an experienced Zoology teacher from Kerala, I’ve compiled this comprehensive resource to help you ace your Zoology board exams.
Why HSSlive Plus One Zoology Previous Year Question Papers PDFs Are Essential
Zoology requires both conceptual clarity and systematic practice. HSSlive.co.in offers the most reliable collection of Plus One Zoology question papers that:
- Help you master the exact Kerala Higher Secondary Board examination pattern
- Reveal frequently tested topics and concepts from past papers
- Develop effective time management strategies
- Build confidence through targeted practice
- Identify your strengths and weak areas in different chapters
How to Download Plus One Zoology Previous Year Question Papers and Answers PDF from HSSlive
Quick Access Guide:
- Visit the official HSSlive website: www.hsslive.co.in
- Navigate to “Previous Question Papers” or “Question Bank” section
- Select “Plus One” from the class options
- Choose “Zoology” from the subject list
- Download the PDF files for different years (2014-2024)
Pro Tip: Create a dedicated folder to organize your HSSlive Zoology PDFs by year for structured revision.
Kerala Plus One Zoology Exam Pattern (Important for HSSlive PDF Users)
Understanding the exact question paper structure will help you extract maximum value from HSSlive PDFs:
| Section | Question Type | Marks per Question | Number of Questions |
|---|---|---|---|
| Part A | Very Short Answer | 1 mark | 10 questions |
| Part B | Short Answer | 2 marks | 12 questions |
| Part C | Short Essay | 3 marks | 6 questions |
| Part D | Long Essay | 5 marks | 2 questions |
| Total | 60 marks | 30 questions |
10 Plus One Zoology Previous Year Question Papers with Answers (HSSlive PDF Collection)
1. March 2024 Zoology Question Paper with Answers
Question 1: What is the basic unit of classification according to Linnaeus? (1 mark) Answer: Species is the basic unit of classification according to Linnaeus.
Question 2: Compare homologous and analogous organs with examples. (2 marks) Answer:
- Homologous organs: Structures with common ancestry but different functions (e.g., forelimbs of humans, whales, bats, and horses)
- Analogous organs: Structures with different ancestry but similar functions (e.g., wings of birds and insects)
Question 3: Explain the process of urine formation in humans. (5 marks) Answer: Urine formation occurs in nephrons through three processes:
- Glomerular Filtration:
- Blood pressure forces small molecules from blood into Bowman’s capsule
- Forms glomerular filtrate containing water, glucose, amino acids, salts, and waste products
- Blood cells and proteins remain in blood
- Tubular Reabsorption:
- Useful substances like glucose, amino acids, and some water are reabsorbed into blood
- Occurs mainly in proximal convoluted tubule (PCT)
- Active and passive transport mechanisms involved
- Tubular Secretion:
- Additional waste products are secreted from blood into nephron tubule
- Helps regulate blood pH and eliminate drugs and toxins
- Occurs mainly in distal convoluted tubule (DCT)
The final urine contains water, urea, uric acid, creatinine, and excess salts, which passes through collecting duct to ureter and bladder for excretion.
2. March 2023 Zoology Question Paper with Answers
Question 1: Name the respiratory pigment found in earthworm. (1 mark) Answer: Hemoglobin dissolved in plasma (not contained in blood cells)
Question 2: Differentiate between exocrine and endocrine glands with examples. (3 marks) Answer:
- Exocrine Glands:
- Have ducts to transport secretions
- Release secretions onto epithelial surfaces
- Examples: Salivary glands, sweat glands, sebaceous glands, pancreatic acini
- Endocrine Glands:
- Ductless glands
- Release hormones directly into bloodstream
- Examples: Pituitary, thyroid, adrenal, pancreatic islets of Langerhans
Question 3: Explain the different types of joints in the human skeletal system with suitable examples. (5 marks) Answer:
- Fibrous Joints:
- No joint cavity
- Connected by fibrous tissue
- Examples: Sutures between skull bones, syndesmosis between tibia and fibula
- Cartilaginous Joints:
- Connected by cartilage
- Allow slight movement
- Examples: Pubic symphysis, intervertebral discs
- Synovial Joints:
- Possess synovial cavity filled with synovial fluid
- Allow free movement
- Types include:
- Ball and socket joints (hip, shoulder): Rotation in all planes
- Hinge joints (elbow, knee): Movement in one plane
- Pivot joints (atlas-axis vertebrae): Rotational movement
- Gliding joints (carpals, tarsals): Sliding movement
- Saddle joints (carpometacarpal of thumb): Movement in two planes
- Condyloid joints (wrist): Movement in two planes but no rotation
3. March 2022 Zoology Question Paper with Answers
Question 1: Name the phylum in which canal system is found. (1 mark) Answer: Phylum Porifera (sponges)
Question 2: Draw a well-labeled diagram of a neuron. (2 marks) Answer: [A diagram showing a typical neuron with labeled parts: cell body/soma, dendrites, axon, myelin sheath, nodes of Ranvier, and axon terminals]
Question 3: Describe the structure and functions of different types of epithelial tissues with suitable diagrams. (5 marks) Answer:
- Simple Squamous Epithelium:
- Single layer of flat cells
- Functions: Diffusion, filtration, secretion
- Found in: Alveoli of lungs, blood vessels, Bowman’s capsule
- Simple Cuboidal Epithelium:
- Single layer of cube-like cells
- Functions: Secretion and absorption
- Found in: Kidney tubules, thyroid follicles, salivary ducts
- Simple Columnar Epithelium:
- Single layer of tall cells
- Functions: Absorption and secretion
- Found in: Digestive tract, gall bladder
- May have microvilli (brush border) or cilia
- Stratified Squamous Epithelium:
- Multiple layers of cells, with flattened upper layers
- Function: Protection against abrasion
- Found in: Skin, esophagus, vagina
- Stratified Cuboidal and Columnar Epithelium:
- Multiple layers of cuboidal or columnar cells
- Function: Protection and secretion
- Found in: Sweat glands, pharynx
- Pseudostratified Columnar Epithelium:
- Single layer that appears stratified
- May have cilia
- Functions: Secretion and moving mucus
- Found in: Respiratory tract, parts of male reproductive tract
- Glandular Epithelium:
- Specialized for secretion
- Forms exocrine and endocrine glands
- Examples: Salivary glands, pancreas
4. March 2021 Zoology Question Paper with Answers
Question 1: Name the largest cell in the human body. (1 mark) Answer: Ovum (female egg cell)
Question 2: Write the functions of the following: a) Tympanic membrane b) Eustachian tube (2 marks) Answer: a) Tympanic membrane (eardrum): Receives sound vibrations from air and transmits them to the middle ear ossicles b) Eustachian tube: Equalizes air pressure on both sides of the eardrum and drains mucus from the middle ear to the pharynx
Question 3: Describe the structure and functions of the human heart. (5 marks) Answer: Structure of the Human Heart:
- Located in the thoracic cavity between the lungs
- Size of a closed fist, about 300g in adults
- Four-chambered with two atria and two ventricles
- Protected by pericardium (double-walled sac)
- Walls composed of cardiac muscle (myocardium)
- Right and left sides separated by interatrial and interventricular septa
- Contains four valves:
- Tricuspid valve (between right atrium and right ventricle)
- Pulmonary valve (between right ventricle and pulmonary artery)
- Bicuspid/mitral valve (between left atrium and left ventricle)
- Aortic valve (between left ventricle and aorta)
Functions of the Human Heart:
- Blood Circulation:
- Right side receives deoxygenated blood from body and pumps it to lungs
- Left side receives oxygenated blood from lungs and pumps it to body
- Cardiac Cycle:
- Coordinated contraction (systole) and relaxation (diastole) of chambers
- Atrial systole followed by ventricular systole
- One complete heartbeat includes atrial systole, ventricular systole, and complete cardiac diastole
- Regulation of Blood Flow:
- Valves ensure unidirectional flow of blood
- SA node (pacemaker) generates impulses for contraction
- AV node transmits impulses from atria to ventricles
- Purkinje fibers distribute impulses throughout ventricular walls
- Maintaining Blood Pressure:
- Forceful contraction of left ventricle maintains arterial blood pressure
- Cardiac output adjusts according to body’s oxygen demands
5. March 2020 Zoology Question Paper with Answers
Question 1: Define parthenogenesis. (1 mark) Answer: Parthenogenesis is a type of asexual reproduction in which an unfertilized egg develops into a new individual without fertilization.
Question 2: What is counter-current flow? How does it help in gas exchange in gills? (3 marks) Answer: Counter-current flow refers to the arrangement where water flows over the gills in one direction while blood flows in the opposite direction.
How it helps in gas exchange:
- Maintains a continuous concentration gradient along the entire length of the gill
- Allows oxygen to diffuse from water to blood even when blood oxygen levels are relatively high
- Maximizes extraction efficiency (up to 80-90% of available oxygen)
- Creates a multiplier effect that maintains diffusion of oxygen throughout the entire gill surface
- Much more efficient than parallel flow, where maximum efficiency would be 50%
Question 3: Explain the mechanism of muscle contraction with the help of sliding filament theory. (5 marks) Answer: Sliding Filament Theory of Muscle Contraction:
- Structure of Sarcomere:
- Basic functional unit of muscle fiber
- Contains thick filaments (myosin) and thin filaments (actin, tropomyosin, troponin)
- Z-discs mark sarcomere boundaries
- A-band: region of myosin filaments
- I-band: region of only actin filaments
- H-zone: central region with only myosin
- Role of Calcium:
- At rest, tropomyosin blocks myosin binding sites on actin
- Nerve impulse releases Ca²⁺ from sarcoplasmic reticulum
- Ca²⁺ binds to troponin C, causing conformational change
- Tropomyosin shifts, exposing myosin binding sites on actin
- Cross-Bridge Cycle:
- ATP hydrolysis energizes myosin heads
- Myosin binds to exposed sites on actin, forming cross-bridges
- Power stroke occurs as myosin heads pivot
- Actin filaments pulled toward center of sarcomere
- New ATP binds to myosin, detaching it from actin
- Cycle repeats as long as Ca²⁺ and ATP are available
- Contraction Effect:
- Z-discs move closer together
- I-bands and H-zone shorten
- A-band length remains constant
- Overall sarcomere shortens
- Multiple sarcomeres shortening causes muscle contraction
- Relaxation:
- Ca²⁺ pumped back into sarcoplasmic reticulum
- Tropomyosin blocks binding sites
- Cross-bridge cycling stops
- Elastic recoil returns muscle to resting length
6. March 2019 Zoology Question Paper with Answers
Question 1: Name the first human chromosome to be completely sequenced. (1 mark) Answer: Chromosome 22
Question 2: Differentiate between innate immunity and acquired immunity. (2 marks) Answer: Innate Immunity:
- Present from birth
- Non-specific response
- No memory of pathogens
- Includes physical barriers, phagocytes, inflammation, complement proteins
- First line of defense
Acquired Immunity:
- Develops after exposure to pathogens
- Specific response to particular pathogens
- Has immunological memory
- Involves B and T lymphocytes, antibodies
- Second line of defense
Question 3: Explain the events that occur during menstrual cycle in human females. (5 marks) Answer: The menstrual cycle consists of three main phases:
- Menstrual Phase (Days 1-5):
- Shedding of endometrium if fertilization doesn’t occur
- Low levels of estrogen and progesterone
- FSH secretion begins to increase
- Primordial follicles begin development
- Proliferative/Follicular Phase (Days 6-14):
- Repair and regrowth of endometrium
- Graafian follicle development in ovary
- Rising estrogen levels from developing follicles
- Thickening of endometrium with blood vessels and glands
- LH surge triggers ovulation around day 14
- Secretory/Luteal Phase (Days 15-28):
- Ruptured follicle forms corpus luteum
- Corpus luteum secretes progesterone and estrogen
- Endometrium becomes thick, vascular, and glandular
- If fertilization occurs, hCG maintains corpus luteum
- If no fertilization, corpus luteum degenerates
- Hormone levels drop, triggering menstruation
Hormonal Regulation:
- Hypothalamus secretes GnRH
- GnRH stimulates anterior pituitary to release FSH and LH
- FSH stimulates follicle development
- LH triggers ovulation and corpus luteum formation
- Estrogen and progesterone provide feedback to hypothalamus and pituitary
7. March 2018 Zoology Question Paper with Answers
Question 1: Name the largest gland in human body. (1 mark) Answer: Liver
Question 2: Write the functions of the following: a) Sebaceous glands b) Ceruminous glands (2 marks) Answer: a) Sebaceous glands: Secrete sebum which keeps the skin and hair waterproof, prevents excessive water loss, and has antibacterial properties b) Ceruminous glands: Produce cerumen (ear wax) which protects the ear canal by trapping dust, insects, and microorganisms and prevents drying of the ear canal
Question 3: Explain the process of digestion in the small intestine of humans. (5 marks) Answer: Digestion in Small Intestine:
- Structure of Small Intestine:
- Duodenum (first part), jejunum (middle part), and ileum (last part)
- Inner lining with circular folds (plicae circulares)
- Villi and microvilli increase surface area
- Contains digestive glands and lymphoid tissue (Peyer’s patches)
- Pancreatic Juice:
- Contains enzymes:
- Pancreatic amylase: Breaks down starch to maltose
- Trypsin, chymotrypsin, carboxypeptidase: Digest proteins to peptides
- Pancreatic lipase: Breaks down fats to fatty acids and glycerol
- Nucleases: Break down nucleic acids
- Sodium bicarbonate neutralizes acidic chyme from stomach
- Contains enzymes:
- Bile:
- Produced by liver, stored in gallbladder
- Emulsifies fats (increases surface area for lipase action)
- Activates lipase
- Helps in absorption of fat-soluble vitamins (A, D, E, K)
- Contains bile salts, cholesterol, phospholipids, bile pigments
- Intestinal Juice (Succus Entericus):
- Contains enzymes:
- Maltase: Maltose → glucose
- Lactase: Lactose → glucose + galactose
- Sucrase: Sucrose → glucose + fructose
- Peptidases: Peptides → amino acids
- Nucleosidases and phosphatases: Complete nucleic acid digestion
- Contains enzymes:
- Absorption:
- Monosaccharides, amino acids absorbed by active transport
- Fatty acids and glycerol form chylomicrons, enter lymphatic system
- Water, minerals, vitamins absorbed by diffusion and active transport
- Specialized regions for specific nutrient absorption
- Movement:
- Peristalsis moves food through intestine
- Segmentation mixes food with digestive juices
8. March 2017 Zoology Question Paper with Answers
Question 1: Name the hormone that stimulates milk production in mammals. (1 mark) Answer: Prolactin
Question 2: Differentiate between endoskeleton and exoskeleton with examples. (2 marks) Answer: Endoskeleton:
- Internal skeleton
- Grows with the organism
- Made of cartilage and/or bone
- Provides framework and protection for internal organs
- Examples: Vertebrates (fish, amphibians, reptiles, birds, mammals)
Exoskeleton:
- External skeleton
- Must be shed (molted) to allow growth
- Made of chitin, calcium carbonate, or similar materials
- Provides protection, support, and prevents water loss
- Examples: Arthropods (insects, crustaceans), molluscs (snails)
Question 3: Describe the structure and functions of different types of connective tissues with diagrams. (5 marks) Answer: Types of Connective Tissues:
- Loose Connective Tissue:
- Widely distributed, consists of fibroblasts
- Three types of fibers: collagen, elastic, reticular
- Functions: Supports epithelium, surrounds blood vessels, fills spaces
- Examples: Areolar tissue, adipose tissue
- Dense Connective Tissue:
- Closely packed fibers
- Types: Dense regular (parallel fibers) and dense irregular (random fibers)
- Functions: Provides strength, elasticity, and support
- Examples: Tendons (connect muscle to bone), ligaments (connect bone to bone)
- Specialized Connective Tissues:
- Blood:
- Fluid matrix (plasma) with cells (RBCs, WBCs, platelets)
- Functions: Transport of gases, nutrients, wastes; defense; clotting
- Bone:
- Hard matrix of calcium salts and collagen
- Contains osteoblasts, osteocytes, osteoclasts
- Functions: Support, protection, mineral storage, blood cell formation
- Cartilage:
- Firm, flexible matrix with chondrocytes in lacunae
- Types: Hyaline, elastic, fibrocartilage
- Functions: Support, flexibility, reduces friction
- Adipose Tissue:
- Fat-storing cells (adipocytes)
- Functions: Energy storage, insulation, protection
- Blood:
9. March 2016 Zoology Question Paper with Answers
Question 1: Name the causative agent of amoebiasis. (1 mark) Answer: Entamoeba histolytica
Question 2: How do hormones differ from enzymes? (3 marks) Answer: Hormones:
- Chemical messengers that act at distant sites
- Produced by endocrine glands
- Act in very low concentrations
- Target specific tissues/cells
- Not consumed in reactions they regulate
- Most are proteins, steroids, or amino acid derivatives
- Examples: Insulin, thyroxine, testosterone
Enzymes:
- Biological catalysts that act at the site of production
- Produced by all cells
- Required in higher concentrations
- Acts on specific substrates
- May be consumed or altered during reactions
- Almost all are proteins
- Examples: Amylase, pepsin, lipase
Question 3: Describe the structure and functions of the human brain. (5 marks) Answer: Human Brain Structure and Functions:
- Forebrain (Prosencephalon):
- Cerebrum:
- Largest part of brain, divided into right and left hemispheres
- Surface covered with gray matter (cerebral cortex) with gyri and sulci
- Divided into frontal, parietal, temporal, and occipital lobes
- Functions: Higher mental activities, sensory perception, voluntary motor control, language, personality, memory
- Diencephalon:
- Thalamus: Relay center for sensory impulses to cerebral cortex
- Hypothalamus: Controls autonomic nervous system, regulates body temperature, hunger, thirst, emotions; connects to pituitary gland
- Cerebrum:
- Midbrain (Mesencephalon):
- Contains centers for visual and auditory reflexes
- Superior and inferior colliculi for visual and auditory processing
- Cerebral peduncles connect forebrain and hindbrain
- Red nucleus involved in motor coordination
- Hindbrain (Rhombencephalon):
- Cerebellum:
- Second largest part of brain with two hemispheres
- Functions: Coordination of voluntary movements, maintenance of posture and balance
- Pons:
- Bridge connecting cerebellum with medulla oblongata
- Contains nuclei for cranial nerves V to VIII
- Regulates respiratory rate
- Medulla Oblongata:
- Continues as spinal cord
- Contains vital centers for heart rate, blood pressure, breathing
- Contains nuclei for cranial nerves VIII to XII
- All ascending and descending tracts pass through it
- Cerebellum:
- Protective Coverings:
- Three meninges: Dura mater (outermost), arachnoid mater (middle), pia mater (innermost)
- Cerebrospinal fluid (CSF) provides mechanical protection and nutrient exchange
10. March 2015 Zoology Question Paper with Answers
Question 1: What is natality? (1 mark) Answer: Natality refers to the number of births in a population during a given period.
Question 2: What are synapses? Explain the transmission of nerve impulse across a chemical synapse. (3 marks) Answer: Synapse: Junction between two neurons or between a neuron and an effector organ where nerve impulses are transmitted.
Transmission across chemical synapse:
- Arrival of action potential at presynaptic terminal
- Voltage-gated calcium channels open, allowing Ca²⁺ influx
- Ca²⁺ triggers fusion of synaptic vesicles with presynaptic membrane
- Neurotransmitters (e.g., acetylcholine) released into synaptic cleft
- Neurotransmitters bind to specific receptors on postsynaptic membrane
- This may cause:
- Opening of ion channels (ionotropic receptors) OR
- Activation of G-proteins (metabotropic receptors)
- Resulting ion movement may be excitatory (depolarization) or inhibitory (hyperpolarization)
- Neurotransmitter action terminated by:
- Enzymatic degradation (e.g., acetylcholinesterase)
- Reuptake by presynaptic neuron
- Diffusion away from synapse
Question 3: Explain the structure and functions of the human excretory system with a neat diagram. (5 marks) Answer: Human Excretory System:
Structure:
- Kidneys:
- Bean-shaped organs located in posterior abdominal wall
- Protected by adipose tissue and renal capsule
- Divided into outer cortex and inner medulla
- Functional unit is nephron (about 1 million per kidney)
- Each nephron consists of:
- Malpighian corpuscle (glomerulus + Bowman’s capsule)
- Proximal convoluted tubule (PCT)
- Loop of Henle
- Distal convoluted tubule (DCT)
- Collecting duct
- Ureters:
- Thin muscular tubes (25-30 cm long)
- Carry urine from renal pelvis to urinary bladder
- Peristaltic movements push urine downward
- Urinary Bladder:
- Muscular sac that stores urine
- Can expand to hold 400-500 ml of urine
- Internal urethral sphincter at junction with urethra
- Urethra:
- Tube carrying urine from bladder to outside
- Longer in males (about 20 cm) than females (about 4 cm)
- External urethral sphincter controls voluntary urination
Functions:
- Excretion:
- Removal of nitrogenous wastes (urea, uric acid, creatinine)
- Elimination of toxins, drugs, excess ions
- Osmoregulation:
- Maintenance of water and electrolyte balance
- Regulation of blood volume and blood pressure
- Acid-Base Balance:
- Regulation of blood pH by selective secretion/absorption of H⁺ and HCO₃⁻
- Metabolic Functions:
- Activation of vitamin D to calcitriol
- Production of erythropoietin (stimulates RBC production)
- Gluconeogenesis during prolonged fasting
- Endocrine Function:
- Production of renin (blood pressure regulation)
- Production of erythropoietin (stimulates RBC production)
Tips to Make the Most of HSSlive Plus One Zoology Previous Year Question Papers
- Create a study schedule dedicating specific time to each chapter
- Practice regularly and time yourself to improve speed
- Focus on frequently asked questions from each chapter
- Create short notes from your analysis of previous years’ papers
- Revise diagrams as they carry significant marks
- Analyze your performance to identify weak areas
Most Important Chapters Based on Previous Year Question Papers
Based on the analysis of past 10 years of HSSlive Plus One Zoology question papers, these chapters carry maximum weightage:
- Structural Organization in Animals
- Cell Structure and Function
- Human Physiology
- Animal Kingdom
- Biomolecules
Prepare these chapters thoroughly for excellent results!
Remember, consistent practice using these HSSlive Plus One Zoology previous year question papers is the key to mastering the subject and scoring high marks in your examination. All the best!