Biology - Online Test
Q1. A DNA segment which serves as a kind of “ON-OFF switch” for transcription is a/an
Answer : Option A
Explaination / Solution:
An operator is a segment of DNA to which a transcription factor binds to regulate gene expression by repressing it. The protein that does this is called a repressor. Repressors bind to operators to prevent transcription.
The main operator (O2) in the classically defined lac operon is located slightly downstream of the promoter. Two additional operators, O1 and O3 are located at -82 and +412, respectively. Operator attach with template strand to initiate transcription process.
Q2. Electrons from excited chlorophyll molecules of photosystem II to photosystem I transferred and finally convert
Answer : Option A
Explaination / Solution:
After absorbing light,electrons are excited and transferred through PS II and PS I and finally to NAD forming NADH.
Q3. The major factor which affect binding related to the partial pressure of carbon dioxide is
Answer : Option B
Explaination / Solution:
is carried by haemoglobin as carbamino-haemoglobin. This binding is related to the partial pressure of . is a major factor which could affect this binding.
Q4. A group of animals related by descent and similar characters like appearance, size and configuration are known as
Answer : Option B
Explaination / Solution:
Breed is a group of animals related by descent and similar characters like appearance, size and configuration. All the animals falling to same breed are capable to breed in between.
Q5. In which of the following protected areas land patches will be permitted for grazing, plantation and cultivation?
Answer : Option C
Explaination / Solution:
Biosphere reserve is generally a vast protected area of land patches divided into three zone, core, buffer and transition zone. A transition zone May contain a variety of agricultural activities, grazing, plantation cultivation And settlements and other uses and in which local communities, management agencies, scientists, non-governmental organizations, cultural groups, economic interests and other stakeholders work together to manage and sustainably.
Q6.
Read the following statements about suprarenal glands :
i. A suprarenal gland represents two endocrine glands arranged in one organ.
ii. It’s outer region secretes steroid hormones.
iii. Also known as gland of emergency.
Answer : Option B
Explaination / Solution:
The adrenal glands (also known as suprarenal glands) are endocrine glands that produce a variety of hormones including adrenaline and the steroids aldosterone and cortisol. They are found above the kidneys. Also Known as the emergency gland of the body.This is because it produces a homone called ADRENALIN which prepares our body from emergencies
Q7. Which among the following is oviparous?
Answer : Option A
Explaination / Solution:
Platypus is the oviparous that lays eggs.
Q8. The middle layer of uterus is thick muscular myometrium that help in
Answer : Option D
Explaination / Solution:
The middle layer of uterus is thick and muscular structure called myometrium that help in exhibiting strong contraction during delivery of the baby.
Q9. The nucleotide chemical components are
Answer : Option A
Explaination / Solution:
The nucleotide has three chemically distinct components. One is a heterocyclic compound, the second is a monosaccharide and the third a phosphoric acid or phosphate.
Q10. When chromosome sets are present in multiple of ‘n’ the condition is called
Answer : Option B
Explaination / Solution:
Most of the organisms are diploid, contain two set of chromosome (2n) but a number of organisms contains multiple of chromosome set like 3n,4n, 6n etc. This condition of having multiple sets chromosome is called Euploidy.
