Basic genetics and Mendel's Law

Question 1

phenotype

Answer 1

observable characteristic of an organism

Question 2

gene

Answer 2

an inherited factor that determines a characteristic

Question 3

allele

Answer 3

alternative versions of a gene

Question 4

homozygous

Answer 4

when the alleles are the same

Question 5

heterozygous

Answer 5

when the alleles are different

Question 6

dominant allele

Answer 6

the allele that expresses itself

Question 7

recessive allele

Answer 7

allele which is unable to express itself

Question 8

who stated the basics of genetics and hereditary?

Answer 8

Gregor Mendel

Question 9

why did Gregor Mendel analyze pisum sativum (pea plants)?

Answer 9

1. easy plant to grow
2. many different characteristics present in 2 alternative forms
3. each plant can generate many other plants

Question 10

how many characteristics did Gregor Mendel analyze?

Answer 10

7

Question 11

describe the cross between pea plants of different pure lineages for the same pure characteristic.

Answer 11

1. 2 diploid individuals with opposite phenotypes produce haploid gametes during meiosis
2. the fusion of the male and female gametes produces zygotes from which diploid individuals of the progeny originate
3. the analysis of the phenotypes of the progeny gives information regarding how the phenotypes are passed to the progeny

Question 12

describe Gregor Mendel’s experiment

Answer 12

he started with crosses between plants of the same pure lineages. then he crossed pea plants of different pure lineages for the same characteristic. in the F1 generation, only one of the 2 phenotypes is visible. then he crossed the pea plants of the F1 generation and in the F2 generation both phenotypes were observed in the ratio 3:1

Question 13

what were the conclusions from Gregor Mendel’s experiment?

Answer 13

1. law of segregation
2. law of independent assortment
3. some alleles are dominant others are recessive

Question 14

law of segregation

Answer 14

when an organism makes gametes, each gamete receives just one copy which is selected randomly

Question 15

law of independent assortment

Answer 15

the alleles of one gene sort into gametes independently of the alleles of another gene