Biology - Online Test
Q1. The cone of Gymnosperms represent the
Answer : Option C
Explaination / Solution:
In gymnosperms, male and female cones are formed that produce male and female gametes.The strobili bearing microsporophylls and microsporangia are called microsporangiate or male strobili. The cones bearing megasporophylls with ovules or megasporangia are called macrosporangiate or female strobili. So, cone of gymnosperms represents the reproductive organs.
Q2. The chromatin contains some basic proteins are called as
Answer : Option A
Explaination / Solution:
Histone proteins are the basic packer and arranger of chromatin.
Q3. Balbiani rings are the sites of
Answer : Option C
Explaination / Solution:
A Balbiani ring is a large chromosome puff. Balbiani rings are diffused uncoiled regions of the polytene chromosome that are sites of RNA transcription and protein synthesis.
They are formed in eukaryotic cells only.
Q4. Light reaction otherwise called as
Answer : Option D
Explaination / Solution:
Light reactions or the ‘Photochemical’ phase include light absorption, water splitting, oxygen release, and the formation of high-energy chemical intermediates, ATP and NADPH. Several complexes are involved in the process.
Q5. The specialized centre which can reduce the inspiratory duration upon stimulation is
Answer : Option C
Explaination / Solution:
The pneumotaxic centre can moderate the functions of the respiratory rhythm centre. Neural signal from this centre can reduce the duration of inspiration and thereby alter the respiratory rate.
Q6. Which one is not a common fresh water fish
Answer : Option C
Explaination / Solution:
Hilsa is not a common fresh water fish. It is a marine fish. Common fresh water fish are Catla, Rohu and Common carp.
Q7. Nowadays,the greatest cause for extinction or biodiversity loss is
Answer : Option C
Explaination / Solution:
The greatest cause for extinction or biodiversity loss is the habit alteration. Deforestation causes loss of habits of a number of wild animals. Pollution of water also alter the habitat of aquatic organisms.
Q8. Glucose will be lost in the urine of patients suffering from :
Answer : Option C
Explaination / Solution:
Glucose will be lost in the urine of patients suffering from diabetes mellitus. It a chronic lifelong condition that affects our body ability to use the energy found in blood.
Q9. The presence of milk producing glands is a unique characteristic feature of class
Answer : Option D
Explaination / Solution:
Mammalia are found in a variety of habitats – polar ice caps, deserts, mountains,forests, grasslands and dark caves. Some of them have adapted to fly orlive in water. The most unique mammalian characteristic is the presenceof milk producing glands (mammary glands) by which the young onesare nourished. They have two pairs of limbs, adapted for walking, running,climbing, burrowing, swimming or flying.
Q10. The correct order of uterus layers form outside to inside is
Answer : Option A
Explaination / Solution:
The wall of uterus has three layers of tissues. The outer most thin layer is called perimetrium followed by thick layer of smooth muscles, myometrium and innermost glandular tissue is endometrium.
