NEET Botany 3 — Questions and Answers
Question 1: Which of the following processes occurs in the stroma of chloroplasts?
- Light reactions
- Photolysis of water
- Calvin cycle (Correct answer)
- ATP synthesis via ETC
Correct answer: Calvin cycle
The Calvin cycle (dark reactions) takes place in the stroma of chloroplasts, where CO2 is fixed and carbohydrates are synthesized.
Question 2: Secondary growth in dicot stems occurs due to activity of:
- Apical meristem
- Intercalary meristem
- Lateral meristem (vascular cambium) (Correct answer)
- Protoderm
Correct answer: Lateral meristem (vascular cambium)
Vascular cambium (lateral meristem) is responsible for secondary growth, producing secondary xylem (wood) and secondary phloem.
Question 3: The term 'totipotency' in plants means:
- Ability of a cell to divide indefinitely
- Ability of a cell to regenerate a complete plant (Correct answer)
- Resistance of plants to pathogens
- Capacity for double fertilization
Correct answer: Ability of a cell to regenerate a complete plant
Totipotency is the ability of a single plant cell to develop into a complete organism, which is the basis of plant tissue culture.
Question 4: Which pigment absorbs red and far-red light and controls photoperiodism?
- Chlorophyll a
- Carotenoids
- Phytochrome (Correct answer)
- Anthocyanin
Correct answer: Phytochrome
Phytochrome is a photoreceptor pigment that exists in two interconvertible forms (Pr and Pfr) and regulates photoperiodism and other light-mediated responses.
Question 5: Which of the following is an example of a syncarpous gynoecium?
- Ranunculus
- Michelia
- Tomato (Correct answer)
- Rose
Correct answer: Tomato
Tomato has a syncarpous gynoecium where the carpels are fused together, unlike apocarpous gynoecia where carpels are free.
Question 6: The law of limiting factors in photosynthesis was proposed by:
- Blackman (Correct answer)
- Emerson
- Calvin
- Hill
Correct answer: Blackman
Blackman's law of limiting factors states that when a process is conditioned by multiple factors, its rate is determined by the factor present in minimum quantity.
Question 7: Casparian strips in root endodermis are composed of:
- Cellulose and pectin
- Suberin and lignin (Correct answer)
- Cutin and wax
- Hemicellulose and protein
Correct answer: Suberin and lignin
Casparian strips are bands of suberin and lignin deposits on the radial and transverse walls of endodermal cells that prevent apoplastic water movement.
NEET Botany 3
Which of the following processes occurs in the stroma of chloroplasts?