B12 Reproduction

Question 1

What is asexual reproduction

Answer 1

Asexual reproduction only involves one parent so there is no joining of sex cells during fertilisation.

Question 2

What is sexual reproduction

Answer 2

The formation of a new organism by combining the genetic material of two organisms.

Question 3

How many cells does the body have?

Answer 3

46

Question 4

What is meisois

Answer 4

Meiosis is the type of cell division that produces gametes . A human body cell contains 46 chromosomes arranged in 23 pairs.

Question 5

What are gametes

Answer 5

Sex cells are also known as gametes. Male gametes are made by male reproductive structures. Female gametes are made by female reproductive structures. A gamete contains a single set of chromosomes in its nucleus and is said to be haploid .

Question 6

What is variation

Answer 6

Difference between individual organisms

Question 7

Phenotype

Answer 7

The physical appearance/biochemistry of an individual for a particular characteristic

Question 8

Genotype

Answer 8

The genetic make up of an individual for a particular characteristic, for example hair or eye colour

Question 9

Gene

Answer 9

The basic unit of genetic material inherited from our parents. A gene is a section of a DNA which controls part of a cell’s chemistry – particular protein production

Question 10

Allele

Answer 10

Different form of the same gene sometimes referred to as variants

Question 11

Dominant

Answer 11

The phenotype will be apparent in the offspring even if only one of the alleles is inherited

Question 12

Recessive

Answer 12

A phenotype that will only show up in the offspring if both of the alleles coding for that characteristic are inhertited

Question 13

Homozygous

Answer 13

Individual with identical alleles for a characteristic

Question 14

Heterozygous

Answer 14

Individual with different alleles for characteristic

Question 15

What is fertilisation

Answer 15

Fertilisation is the fusion of the nucleus of a male gamete with the nucleus of a female gamete, producing a new cell called a zygote .

Question 16

How are gametes formed

Answer 16

Cells in the reproductive organs divide them meiosis to form the gametes

Question 17

What is the process of meiosis

Answer 17

The genetic material is copied and then the cells divides twice to form for gametes each with a single set of chromosomes

Question 18

Where do you gametes join

Answer 18

Gametes join at fertilisation to restore the normal number of chromosomes. The new cell divides by mitosis. The number of cells increase and as the embryo develops, the cells differentiate

Question 19

What is a human genome

Answer 19

The genome of an organism is the entire genetic material of that organism

Question 20

What is DNA

Answer 20

The genetic material in the nucleus of a cell is composed of DNA. DNA is a polymer made up of two strands forming a double helix

Question 21

What is a Punnett Square

Answer 21

A way of modelling a genetic cross and predicting the outcome using probability

Question 22

Sex Chromosome

Answer 22

Carry the information that determines the sex of an individual

Question 23

Polydactyl

Answer 23

Polydactyly is a dominant phenotype caused by a dominant allele which can be inherited from either or both parents

Question 24

What is cystic fibrosis

Answer 24

Cystic fibrosis is a recessive phenotype and is caused by recessive alleles which must be inherited from both parents

Question 25

What are carriers

Answer 25

Individuals who are heterozygous for a recessive allele linked to a genetic disorder. Carriers have one healthy are you so they are not affected themselves but they can pass on the affected allele to their offspring

Question 26

Haploid

Answer 26

Cells contain one version of each chromosome

Question 27

Diploid

Answer 27

Cells contain pairs of chromosomes

Question 28

Zygote

Answer 28

When gametes fuse they create a diploid cell