Inheritance

Question 1

What Is A Chromosome?

Answer 1

A chromosome is a structure in a cell that carries genetic information.

Question 2

What Is A Gene?

Answer 2

A gene is a small segment of DNA that codes for protein. It determines the physical traits and functions of an organism.

Question 3

How Many Autosomal Chromosomes Do Males And Females Have?

Answer 3

Males and females have 44 autosomal chromosomes.

Question 4

How Many And What Sex Chromosomes Do Males And Females Have?

Answer 4

Males and females have 2 sex chromosomes. Males have X and Y, while females have X and X.

Question 5

How Many Chromosomes Do Gametes Have And What Are Their Sex Chromosomes?

Answer 5

Gametes have 22 autosomal chromosomes and 1 sex chromosome. For sperm cells, this will be either X or Y, and for ovum cells have X.

Question 6

What Is A Diploid Cell?

Answer 6

A diploid cell has 44 autosomal chromosomes and 2 sex chromosomes. It has the full number of chromosomes, and can be found in most parts of the body.

Question 7

What Is A Haploid Cell?

Answer 7

A haploid cell has half the number of chromosomes (22 autosomal chromosomes and 1 sex chromosome). It is only found in reproductive organs.

Question 8

What Is Mitosis?

Answer 8

Mitosis is a process where a diploid cell makes a copy of itself, to produce two identical daughter cells, to assist with growth and repair.

Question 9

What Is Meoisis?

Answer 9

Meiosis is a process where diploid cells divide twice to produce four haploid cells. This only occurs in sex organs and means that the cells have half the number of chromosomes.

Question 10

Why Do Gametes Have Half The Number Of Chromosomes Of Body Cells?

Answer 10

There are half the number of chromosomes in a cell, so when fertilisation occurs, the zygote will have the complete number of chromosomes. 26 chromosomes + 26 chromosomes = 46 chromosomes.

Question 11

What Are The Roles, Locations, And Outcomes Of Mitosis And Meiosis?

Answer 11

Meiosis’s role is sexual reproduction, used to make gametes. Mitosis’s role is asexual to assist with growth and repair. Meiosis only occurs in the reproductive organs, while mitosis occurs almost everywhere in the body. Meiosis’s outcome is 4 unidentical haploid cells. Mitosis’s outcome is 2 identical diploid daughter cells.

Question 12

What Is Fertilisation?

Answer 12

Fertilisation is the union of nuclei in the female and male cells to create new life (a zygote).

Question 13

How Is Sex Inherited?

Answer 13

When the cells divide during meiosis, each cell has half the number of chromosomes. The sex chromosomes in an egg cell will be X, however, in a sperm cell, they’ll be either X or Y. Whichever sperm cell fertilises the egg first will determine the gender of the baby.

Question 14

What Are Alleles And An Example Of One?

Answer 14

An allele is a variation of a gene. For example blue eyes or brown hair.

Question 15

What Is A Genotype?

Answer 15

A genotype is the combination of alleles an organism has for a gene. For example, NN, Nn, nn.

Question 16

What Is A Phenotype?

Answer 16

A phenotype is the trait that is expressed by an organism for a gene. For example, blonde hair, blood clotting, or brown eyes.

Question 17

What Is Dominant And Recessive Inheritance?

Answer 17

A dominant allele is the trait that is expressed. A recessive allele will be masked, and not shown.

Question 18

What Is Sex Linked Inheritance?

Answer 18

When the gene appears on the X chromosome but doesn’t have an equivalent on the Y chromosome, it’s referred to as sex-linked.

Question 19

What Is A Chromosomal Mutation?

Answer 19

A change in the number of chromosomes in a cell.

Question 20

What Is A Gene Mutation?

Answer 20

An alteration to the DNA base sequence of a gene.

Question 21

What Are Three Factors That Contribute To Increasing The Rate Of DNA mutations?

Answer 21

Exposure to mutagenic chemicals, ionising radiation, high temperature.