Mendel

Question 1

Who was Gregor mendel

Answer 1

Austrian monk, naturalist, known as father of genetics

Used pea plants to demonstrate hereditary

No knowledge of chromosomes at the time

Question 2

5 reasons why mendel was successful

Answer 2

Repeated crosses many times

Used rules of Probability

Controlled pollination

Could study many generations

Pea plants have many traits that appear in 2 different forms (tall vs short)

Question 3

Trait

Answer 3

A specific characteristic or feature exhibited by an organism

Question 4

What was Mendels expierement

Answer 4

Studied self fertilizing plants to produce offspring with consistent traits generation after generation

He performed crosses, crossed true breeding plant w one form of a trait

Called these P generation (parents, generation)

Question 5

True breeding organisms

Answer 5

Pass on same traits generation after gen

Question 6

Cross

Answer 6

Fertilization of a female gamete with a male gamete

Question 7

P generation:

Answer 7

Organisms initially being crossed

Question 8

Monohybrid cross

Answer 8

Only 1 trait being looked at eg only seed colour

Question 9

Alleles

Answer 9

Different versions of a gene

Question 10

Law of dominance

Answer 10

Dominant Allele will always express itself when present in genotype

Ressesckve will only express when 2 copies of ressesive allele is present in genotype (rr)

Question 11

Why is mendel the father of genetics?

Answer 11

Established true breeding

Crossed true breedin*lines

Obvserved patterns in offsprings

Identified dominant and ressesive

Identified mathematical ratios

Came up w laws of inheritance

Question 12

Law of segregation

Answer 12

Pair of alleles for a given trait are segregated when gametes are formed

Eg Tt = gametes t and T

Each gamete contains only one of the alleles

Question 13

Test cross/back cross

Answer 13

Used when organism has dominant phenotype, and we don’t know if it is homozygous dom (FF) or hetero (Ff)

To find out, cross dominant phenotype w homozygous recessive organism (rr)

Question 14

Dihybrid cross

Answer 14

Crossing involving 2 traits, eg round and tall or wrinkled and short

Question 15

What is the dihybrid phenotypic ratio (homo dom and homo rec)

Answer 15

9:3:3:1

9 is dominant forms of both traits (YyRr)
3 is offspring of one recessive form of a trait and one dominant form of the second traits (yyRR)
3 offspring displaying opposite combo of ressesicvd and dom forms (YYrr)
1 offspring with recessive forms of both (yyrr)

Question 16

Independent assortment

Answer 16

Since all combos are seen, alleles controlling diff traits are inherited independently of eachother

Alleles of 2 or more traits seperate (assort) independently of another

Eg parent plane is TtRr then produce 4 diff gamete combos (TR, Tr, Rt, rt)

Question 17

What did boveri-sutton do and what theory

Answer 17

Chromosome theory of inheritance

Proposed that chromosomes are the basis of heredity and genes are on chromosomes (1901-2)