inheritance

Question 1

what is the genotype

Answer 1

the genetic information of an organism and describes all the alleles an organism has

Question 2

what is phenotype

Answer 2

observable biochemical characteristics of an organism it is the interaction between the genes and the enviroment

Question 3

what is a gene

Answer 3

a section of dna which codes for a protien

Question 4

what are allele

Answer 4

different versions of the same gene

Question 5

what is a locus

Answer 5

the position of a gene on a chromosome

Question 6

what happens when hetrozygous is present

Answer 6

only one of the alele is shown in the phenotype the allele that is expressed is thought to be dominanes and the not expressed iis recessive

Question 7

when is reccessive expressed

Answer 7

when the gentype is homologous recesive

Question 8

what is codominance

Answer 8

when two genes contribute to the phenotype

Question 9

what is pure breeding

Answer 9

must be homozygous for either recessive or dominant

Question 10

what is the law of segregation

Answer 10

in diploid organism the characterisitcs are determined by alleles that occur in pairs only one of each pair of allels can be present in one gamete

Question 11

how to produce 3:1 ratio

Answer 11

when the pure bred reccesive and dominant are bred together, all the offsprings will have a heterozygous genotype and all will have same phenotype, when these f1 generation are bred together will produce a 3:1 ratio

Question 12

whatis monohybrid

Answer 12

is the inheritance of a single gene

Question 13

what is dihybrid

Answer 13

two characteristics are determined by two different genes and are inherited located on two different chromosomes

Question 14

what is the usual dihybrid ration

Answer 14

9:3:3:1

Question 15

what is multiple alleles

Answer 15

more than two alleles of which only two may be present at the locus of individual homologous chromosome

Question 16

what are the male sex chromosome

Answer 16

they are x and y

Question 17

what gamete do women and male produce

Answer 17

females have two x chromosomes so only pass on x chromosomes, males have one x and one y chromosome and there is 50/50 chance that either a y or a x will be passed on so it is 50/50 chance girl or boy

Question 18

what is sex linked

Answer 18

a gene that carries the x or y chromosome

Question 19

why is sex linked disease usually seen in boys

Answer 19

the x chromosome is usually longer than the y chromosome which means that for the most of length of the x chromosome there is no equivalent homologous portion of the y chromosome so even when the characteristics are recessive there is no dominant allele to overide the recessive feature

Question 20

what is haemophillia

Answer 20

the blood clot is slow and infrequent as there may be internal bleeding usually fatal when females mensturate

Question 21

what is the law of assortment

Answer 21

each member of a pair of allele can randomly combine with another pair

Question 22

what is autosomal linkage

Answer 22

two gene that occur on the same chromosome is thought to be linked

Question 23

ration when two hetrozygous parents produce offsprings no crossing over

Answer 23

3:1

Question 24

what happens when two hetrozygous alleles occur on the same chromosome

Answer 24

produce 2 different gametes

Question 25

what does a gene determine

Answer 25

the limit of the expresion and the infleuce of the enviroment

Question 26

what is epistasis

Answer 26

when an allele of one gene masks the expression of another allele