Genetics

Question 1

The information that results in plant and animals having similar characteristics to their parents is carried by

Answer 1

Genes, which are passed on in the sex cells (gametes) from which the off spring develop.

Question 2

The nucleus of a cell contains

Answer 2

Chromosomes

Question 3

Chromosomes carry

Answer 3

Genes that control the characteristics of the body

Question 4

Chromosomes are usually found in

Answer 4

Pairs

Question 5

In human body cells, one of the 23 pairs of chromosome ps carried the genes that determine

Answer 5

Sex

Question 6

In females the sed chromosomes are

Answer 6

The same XX

Question 7

In makes the sex chromosomes

Answer 7

Are different XY

Question 8

Different genes control

Answer 8

The development of different characteristics of an organism

Question 9

Some characteristics are controlled by

Answer 9

A single gene

Question 10

Each gene may have different forms called

Answer 10

Alleles

Question 11

Genes operate at a

Answer 11

Molecular level to develop things that can be seen

Question 12

The individual is homozygous for that gene if

Answer 12

Both chromosomes in a pair contain the same allele of a gene

Question 13

The individual is heterozygous if

Answer 13

The chromosomes in a pair contain different alleles of a gene

Question 14

A dominant allele

Answer 14

Is an allele that controls the development of a characteristic when it is present in only one of the chromosomes

Question 15

A recessive allele

Answer 15

An allele that controls the develop,don’t of a characteristic only if the dominant allele is not present

Question 16

Phenotype

Answer 16

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

Question 17

Genotype

Answer 17

The genetic makeup of an individual regarding a particular characteristic

Question 18

Sexual reproduction

Answer 18

The joining (fusion) of a male and female gametes, the mixture of the genetic information from two parents leads to variety in the offspring

Question 19

Asexual reproduction

Answer 19

No fusion of gametes and only one individual is needed as the parent. There is no mixing of genetic information and so no genetic variation in the offspring. These genetically identical individuals are known as clones

Question 20

What are chromosomes made up of

Answer 20

Large molecules of DNA (deoxyribonucleic acid)

Question 21

DNA contains

Answer 21

The coded information that determines inherited characteristics

Question 22

A gene is

Answer 22

A small section of DNA

Question 23

Each gene codes for

Answer 23

A particular combination of amino acids, to make a specific protein

Question 24

DNA is made of

Answer 24

Very long strands, twisted to form a double helix, which contains four different compounds, called bases

Question 25

Some disorders are

Answer 25

Inherited

Question 26

Polydactyly

Answer 26

Having extra fingers or toes - Is caused by a dominant allele and can therefore be passed on by only one parent who has the disorder

Question 27

Cystic fibrosis

Answer 27

A disorder of cell ,embraces - is caused by a recessive allele.

Question 28

Sickle cell anaemia

Answer 28

A disorder affecting red blood cells - recessive allele

Question 29

So,e inherited conditions are caused by

Answer 29

Inheritance of abmpnotmal numbers of chromosomes, e.g Down's syndrome is caused by the presence of an. Extra chromosome

Question 30

.............. Can be screened for the ........ That cause many genetic disorders

Answer 30

Embryos can be screened for the alleles that cause many genetic disorders

Question 31

Embryo screening

Answer 31

Dna Is isolated from embryo cells A gene probe that will bind onto the gene for s specific disorder is produced. The probe usually has a fluorescent chemical attached to it. The probe I'd added to a mixture containing the Dna sample from the embryo. Uv light is used to detect the probe attached to the gene for the disorder.

Question 32

Concerns about embryo screening includes

Answer 32

The risk of miscarriages The reliability of the information from the screening procedure Decision about terminating pregnancy

Question 33

Differences in the characteristics of individuals of the same kind may be due to differences in

Answer 33

The genes they have inherited (genetic causes) The conditions in which they have developed (environmental causes) A combination of the above