CBSE 11TH BIOLOGY - Online Test
Q1. Carotenes protect plants from
Answer : Option C
Explaination / Solution:
Carotene is present in chloroplast along with chlorophyll pigment. This pigment protect the plants from photo-oxidation during photosynthesis at higher intensity of light.
Q2.
Read the following statements :
i. Every 100 ml of deoxygenated blood delivers about 4 ml of to the alveoli.
ii. 30% - 40% of is transported to the alveoli as carbamino-haemoglobin.
iii. At respiratory surface diffuses from venous blood into alveolar spaces.
Answer : Option A
Explaination / Solution:
20 – 25% of is transported to the alveoli as carbamino-haemoglobin.
Q3. Following conversion in forward and backward directions is regulated as :
Blood calcium Bone calcium
Answer : Option C
Explaination / Solution:
Thyrocalcitonin (TCT) influence the metabolism of calcium inside the body. Parathyroid hormone (PTH) absorption of calcium in bone.
Q4. Air bladder is absent in
Answer : Option B
Explaination / Solution:
Air bladder is absent in chondrichthyes that help in floating in water.
Q5. In most fungi the structural polysaccharide of cell wall is ------
Answer : Option D
Explaination / Solution:
In most fungi the structural polysaccharide of cell wall is chitin. In plant cells cell wall is made up of cellulose.
Q6. Prothrombin plays crucial role in blood coagulation and vitamin K is considered essential for blood clotting, now read the following :
i. Vitamin K is necessary for synthesis of prothrombin in liver.
ii. Vitamin K is necessary for synthesis of prothrombin in bone marrow.
iii. Vitamin K is necessary for conversion of prothrombin into active thrombin.
i. Vitamin K is necessary for synthesis of prothrombin in liver.
ii. Vitamin K is necessary for synthesis of prothrombin in bone marrow.
iii. Vitamin K is necessary for conversion of prothrombin into active thrombin.
Answer : Option B
Explaination / Solution:
Prothrombin plays crucial role in blood coagulation and vitamin K is essential for blood clotting. Vitamin K is necessary for synthesis of prothrombin in liver.
Q7. In kreb cycle, isocitric acid is converted into α-keto glutaric acid by
Answer : Option D
Explaination / Solution:
Citrate is first isomerised to isocitrate and then followed by decarboxylation, leading to the formation of α-ketoglutaric acid.
Q8. Which stage is marked by terminalisation of chiasmata?
Answer : Option C
Explaination / Solution:
Chismata is formed due to crossing over. During diakinesis of prophase I of meiosis terminalisation of chiasmata takes place which indicates end of crossing over and separation of the non-sister chromatids.
Q9. The larvae of urochordates is called
Answer : Option A
Explaination / Solution:
The larvae of urochordates is called tadpole. Tadpolechange into adults by the process of metamorphosis. The structure of tadpole is totally different from the adult ones.
Q10.
Read the following :
i. Infants and toddlers are often under habit of bed wetting since micturition is a reflex process.
ii. Adults and grown up children can control this reflex process, voluntarily to some extent.
Answer : Option C
Explaination / Solution:
The process of release of urine is called micturition and the neural mechanism causing it is called the micturition reflex. Adults and grown up children can control the reflex process of micturition voluntarily to some extent.
