CBSE Class X – Science Biology Exam ( Full Syllabus)

A group of grass hoppers – some green and some brown-lived in grassland having dry bushes and dry grass. Name the phenomeneon

Select correct option about variation?

1. The differences in characteristics between individuals of the same species is called variation.
2. Variations arise in organisms during the process of copying the DNA due to which the DNA copies will be similar but not identical to the original

The first person to give scientific explanation for the mechanism of transmission of characters from parents to the offsprings.

A zygote which has an Y chromosome inherited from the father will develop into a

Which of the following statement is inappropriate?

The two versions of a trait (character) which are brought in by the male and female gametes are located on:

Select the group which shares the maximum number of common characters

Choose the statements that describe the characteristics of genes:

1. Genes are specifc sequence of bases in a DNA molecule
2. A gene does not code for proteins.
3. In individuals of a given species, a specifc gene is located on a particular chromosome.
4. Each chromosome has only one gene

Characters that are transmitted from parents to ofspring during reproduction

The characteristics transmitted from parents to ofspring are present in

Slides of binary fission in Amoeba and budding in yeast were given for observa group of students. Some of the observations reported by the group are given below:

1. Cytokinesis was observed in the yeast cell.
2. A chain of buds were observed in Amoeba.
3. Single cell of Amoeba and single cell of yeast were undergoing binary fission and budding respectively
4. Elongated nucleus was dividing to form two daughter nuclei in Amoeba

Assertion (A): Variation is useful for the survival of species over time. Reason (R) : Populations of organisms fill well-defined places in the ecosystem, using their ability to reproduce

Assertion (A): Vegetative propagation makes possible propagation of plants that have lost the capacity to produce seeds. Reason (R) : New plants are developed from seeds in vegetative propagation.

What is the mode of asexual reproduction in Amoeba?

What is the mode of asexual reproduction in Spirogyra

Tubectomy does not prevent the spread of sexually transmitted diseases.

Which of the subsequent statement(s) is/are true about heart?

Single circulation, i.e., blood fows through the heart only once during one cycle of passage through the body, is manifested by:

Which of the following statements about the autotrophs is inapropriate:

Is it necessary to separate oxygenated and deoxygenated blood in mammals and birds.

If human urine is allowed to stand for sometime, it smells of ammonia, why?

The hormone whose level in the blood is responsible for the above diabetes

Bowman’s capsules of nephrons acts as

Respiratory pigment in human body is

Name an enzyme present in pancreatic juice