ZOOLOGY

ZOOLOGY

Which hormone is secreted by the juxtaglomerular apparatus (JGA) in response to low blood pressure?

The JGA secretes renin in response to low blood pressure, which activates the renin-angiotensin mechanism to increase blood pressure. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which of the following statements about fishes is correct?

Cartilaginous fishes lack an operculum and instead have gill slits for respiration. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Animal Kingdom, Topic: Chondrichthyes, cartilaginous skeleton, absence of swim bladder, placoid scales.

View Details

ZOOLOGY

Which evolutionary concept is supported by the similarity in DNA sequences across diverse organisms?

Similarity in DNA sequences among diverse organisms supports the concept of common ancestry. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which of the following is incorrect about arteries?

Not all arteries carry oxygenated blood. The **pulmonary artery** carries **deoxygenated blood** from the right ventricle to the lungs. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which of the following statements about muscle contraction is correct?

Myosin heads form cross-bridges with actin filaments during muscle contraction​. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which of the following is a method for direct gene transfer into animal lls?

Microinjection is a technique used to introduce foreign DNA directly into the nucleus of animal lls. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which of the following enzymes is used to break down bacterial ll walls during DNA isolation?

Lysozyme breaks down the peptidoglycan ll wall of bacteria to release DNA for isolation. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which polysaccharide is found in bacterial ll walls?

Peptidoglycan is a structural component of bacterial ll walls. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which pathogen is responsible for causing diphtheria?

Diphtheria is caused by Corynebacterium diphtheriae, which produces a toxin affecting the throat and respiratory system. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which structure in the neuron contains synaptic vesicles filled with neurotransmitters?

The axon terminal contains synaptic vesicles filled with neurotransmitters for signal transmission. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which of the following statements about DNA ligase is correct?

DNA ligase seals nicks in the sugar-phosphate backbone by forming phosphodiester bonds between DNA fragments. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details

ZOOLOGY

Which of the following statements about enzymes is incorrect?

Enzymes are not consumed in reactions; they remain unchanged and can be reused. This follows from NCERT principle where relation explains outcome clearly for students.

Ref: NCERT Biology Textbook for Class XI and XII (Zoology section), Chapter: Biology - Zoology portion covering relevant system and function, Topic: Structural organization and physiology.

View Details