genetics

Question 1

gamete?

Answer 1

haploid cell capable of fusion which transmits genes from one generation to the next

Question 2

fertilisation?

Answer 2

fusion of 2 haploid gametes to form a diploid zygote which grows into a new individual

Question 3

homozygous?

Answer 3

cells that contain 2 alleles for a gene that are identical

Question 4

heterozygous?

Answer 4

cells that contain 2 alleles for a gene that are different

Question 5

progeny?

Answer 5

offspring produced

Question 6

codominance?

Answer 6

cross between 2 organisms of different phenotype that produce offspring with a third phenotype in which both parental traits appear together

Question 7

what is Mendel’s law of segregation?

Answer 7

inherited characteristics are controlled by alleles. These alleles separate from each other at gamete formation with only one member of alleles being found at each gamete

Question 8

Law of independent assortment?

Answer 8

at gamete formation, either member of a pair of alleles can combine with either member of another pair of alleles

Question 9

linkage?

Answer 9

genes are located on the same chromosome

Question 10

sex linkage?

Answer 10

means that each gene is located on a sex chromosome

Question 11

variation?

Answer 11

differences between individuals within a species

Question 12

mutation?

Answer 12

change in the amount of structure of DNA

Question 13

causes of genetic mutations?

Answer 13

mutagens= environmental agents that cause mutation

Question 14

genetic disorder?

Answer 14

disease that is caused by an abnormality in a persons DNA

Question 15

evolution?

Answer 15

Inheritable change within a population or species, by natural selection, in response to change in the environment over long periods of time

Question 16

observations of natural selection?

Answer 16

1) organisms produce far more offspring than is needed to maintain the population
2) the population of a species tends to remain the same
3) members of all population show genetic variation

Question 17

natural selection?

Answer 17

the process by which organisms with genetically controlled characteristics allow them to be well adapted to their environment, survive and reproduce to pass on their genes to following generations

Question 18

define genetic engineering?

Answer 18

the artificial manipulation or alteration of genes

Question 19

explain genetic engineering steps?

Answer 19

isolation= locating, identifying and removing a gene

cutting= cutting the DNA using restriction enzymes

introduction of base sequence changes

ligation= joining of DNA or a plasmid

transformation= uptake of DNA by host cell

expression= production of new protein