Vardaan Learning Institute

Ans: (b) Mitochondria
Pyruvate breakdown (Krebs cycle) occurs in mitochondria, releasing energy.

Ans: (a) Larynx
Larynx is the voice box containing vocal cords that vibrate to produce sound.

Ans: (b) Liver
Bile is synthesized in the liver and stored in the gallbladder.

Ans: (b) Saprophytic
Fungi absorb nutrients from dead and decaying organic matter.

Ans: (b) Translocation
Movement of soluble products of photosynthesis is translocation.

Ans: (a) Cytoplasm
In lack of oxygen (muscle cells), pyruvate converts to lactic acid in cytoplasm.

Ans: (d) Glucose $\rightarrow$ Cytoplasm $\rightarrow$ Pyruvate $\rightarrow$ Cytoplasm $\rightarrow$ Ethanol + Carbon dioxide
Anaerobic respiration in yeast (fermentation).

Ans: (d) Heparin
Heparin is an anticoagulant (prevents clotting). Platelets, Fibrinogen, Prothrombin help in clotting.

Ans: (d) Pisces only
Fish have a 2-chambered heart and show single circulation. Blood goes from heart to gills for oxygenation and then to body.

Ans: (c) Osmosis
Movement of water from soil (high concentration) to root hair (low concentration) across a semi-permeable membrane.

Ans: (a) Both A and R are true and R is the correct explanation of A.
Villi provide large surface area for maximum absorption of digested food.

Ans: (a) Both A and R are true and R is the correct explanation of A.
Blood pumped by heart flows at high pressure in arteries, so they need thick elastic walls.

Ans: (c) A is true but R is false.
Plants excrete $O_2$, $CO_2$, water vapor, gums, resins. Urea is excreted by animals.

Ans: (a) Both A and R are true and R is the correct explanation of A.
Left ventricle pumps blood to the whole body (long distance, high pressure), hence thicker walls than right ventricle (which pumps only to lungs).

(Diagram required: Guard cells, Pore).
Function: Regulates opening/closing of stomatal pore for gas exchange and transpiration.

(i) $6CO_2 + 12H_2O \xrightarrow{Sunlight, Chlorophyll} C_6H_{12}O_6 + 6O_2 + 6H_2O$.
(ii) 1. Absorption of light energy. 2. Conversion to chemical energy & splitting of water. 3. Reduction of CO2.

(i) Aerobic: Uses $O_2$, Complete breakdown, High energy (38 ATP), End products $CO_2 + H_2O$.
Anaerobic: No $O_2$, Partial breakdown, Low energy (2 ATP), End products Ethanol/Lactic acid.
(ii) Aquatic organisms breathe faster because dissolved oxygen in water is low compared to oxygen in air.

Xylem: Transports water/minerals, Unidirectional (upwards) flow, Main elements are vessels/tracheids.
Phloem: Transports food (sucrose), Bidirectional flow, Main elements sieve tubes/companion cells.

Blood passes through heart twice: Pulmonary (Heart-Lungs-Heart) and Systemic (Heart-Body-Heart).
Necessary to separate oxygenated and deoxygenated blood for efficient energy supply in mammals/birds (warm-blooded).

1. Ultrafiltration in Glomerulus.
2. Selective Reabsorption in tubular part (Glucose, amino acids).
3. Tubular Secretion of wastes into filtrate.

(i) (Diagram required).
(ii) (a) Saliva: Amylase digests starch.
(b) HCl: Kills germs, activates Pepsin.
(c) Bile: Emulsifies fats, alkalizes food.

(i) (Schematic flow chart/diagram).
(ii) Four chambers to separate oxygenated/deoxygenated blood.
(iii) Valves prevent backflow of blood.

(i) Urea.
(ii) Bowman's Capsule.
(iii) Dialysing fluid lacks nitrogenous wastes, creating a concentration gradient for diffusion of waste from blood.

(i) Glycolysis (Breakdown of Glucose to Pyruvate).
(ii) ATP (Adenosine Triphosphate).
(iii) Due to accumulation of Lactic Acid formed by anaerobic respiration in muscle cells during lack of oxygen.