Basics of Heredity | Heredity and Evolution | Assessment | English | Grade 10

The transfer of various characters from parent to child is called ________.

• Variations

• Heredity

• Evolution

• Trait

Answer explanation

The transfer of various characters from parent to child is called heredity.

Which of the following statement is correct?

• The genes code for a specific cell

• Each chromosome has only one gene

• Gene is a specific part of a chromosome

• Each gene codes for a hormone

Answer explanation

In the cell, DNA forms thin long thread like structure called chromosome. As the gene is a specific path on DNA therefore it is also a specific part of the chromosome. A single chromosome can contain many genes. Hence statement of option 3 is correct. while statement of option 2 is not correct. We know that one gene codes for one specific protein. Hence statement of option 1 and option 4 is not correct.

What is the unit of heredity?

• DNA

• Protein

• Gene

• Character

Answer explanation

The body of an organism is made up of cells. Cells contain nucleus in which deoxyribonucleic acid (DNA) is present. DNA is the source of information for synthesising proteins. The DNA contain specific segments for synthesising specific proteins. This segment is called gene. The gene of a protein regulates the synthesis of protein and in turn regulates the expression of a character. So the expression of characters is controlled by genes, so genes are called unit of heredity.

Natasha is suffering from a hereditary disease. So the doctor will give her treatment at:

• Genetic level

• Cellular level

• Tissue level

• Organ level

Answer explanation

The transfer of various characters from parent to child is called heredity. So the hereditary disease is the disease which is transferred from parent to offspring. So the disease is also the character. Character of parents are transferred to offspring by the gene. This means that the disease from which Natasha is suffering is transferred through gene. Since the disease is because of gene, hence the doctor will give her treatment at genetic level.

Branch of Science in which we study, genes, variations and heredity is called as

• Biotechnology

• Evolution

• Genetics

• Zoology

Answer explanation

Branch of Science in which we study, genes, variations and heredity is called as genetics.

A rose plant has two genes for the expression of flower colour, R and r. So for flower colour, the rose plant is:

• Homozygous

• Heterozygous

• Homologous

• Heterologous

Answer explanation

A gene may have different variants that control different traits. Different forms of the same gene are called alleles. Here rose plant has two different forms of genes for flower colour, R and r. Hence R and r are alleles. The organism that has same pair of alleles for one character are called homozygous. And organisms that have different pairs of alleles for one character are called heterozygous. So for flower colour, the rose plant is heterozygous.

A medicine that inhibits the growth of bacteria or kills the bacteria is called antibiotic. A bacterial culture is sensitive to an antibiotic. But after some generations it was found that some bacteria in the culture are resistant to antibiotic. Which of the following statement is correct? 1. The resistance in few bacteria is variation. 2. This variation will help in the survival of the bacteria in presence of antibiotic. 3. These variations in the reproduction are the basis of evolution.

• Only statement 1

• Only statement 3

• Statement 1 and statement 3

• All statements

Answer explanation

Bacterial culture is sensitive to antibiotic means that bacteria can't live in the presence of antibiotic. But after some generations , few bacteria become resistant to antibiotic. The difference in the character of parent and offspring is called variation. Hence, the resistance in few bacteria is variation. These new bacteria can live in the presence of antibiotic. Hence this variation will help in the survival of the bacteria in presence of antibiotic. We know that the variations in the reproduction are the basis of evolution. Therefore all statements are correct.