Unit 8

Question 1

What is a gene

Answer 1

Information for a trait passed from a parent to an offspring, requires two alleles to function in most cases

Question 2

What is an allele

Answer 2

Alternate forms of a gene ( one can be P and the other p)

Question 3

What is a Phenotype

Answer 3

The observable physical and physiological trait resulting from gene expression

Question 4

What is a genotype

Answer 4

The genetic constitution/set of allele (BB or Bb)

Question 5

What are homozygous genotypes

Answer 5

2 of the same allele

Question 6

What is a heterozygous genotype

Answer 6

Having two different allele

Question 7

What is a hemizygous genotype

Answer 7

Having only one allele because of sex-linked traits

Question 8

What is the difference between autosomes and sex chromosomes

Answer 8

Autosomes are the same, can be written as Bb, BB or bb
Sex chromosome contain X and Y, can be written like this
XBXB, XBXb, XbXb

Question 9

Name the 8 inheritance patterns

Answer 9

-simple dominance
-intermediate/incomplete pattern
-co-dominance
-epistasis
-polygenic
-pleiotropic
-multiple allele: hierarchical
-multiple allele: circular

Question 10

What did mendel contribute to genetics

Answer 10

He figured out:
-how traits are handed down from parent to offspring during gamete formation
-how alleles interact and are expressed in the offspring-simple dominance

Question 11

What are Mendels 3 principles

Answer 11

-principle of segregation
-principle of dominance
-principle of independent assortment

Question 12

What is the principle of segregation

Answer 12

Genes of one parent behaves as pairs and seperate so that each gamete contains only one of the two

Question 13

What is Principle of dominance

Answer 13

When alternate forms of a gene are together and one hides the expression of the other=dominant/recessive

Question 14

What is principle of independent assortment

Answer 14

When 2 different traits/genes are located on different chromosomes, the alleles assort independently into gametes during meiosis

Question 15

Why are garden pea plants a good genetic tool?

Answer 15

-pea hybrids could be produced and many pea varieties
-one plant produced many offspring
-pea plants are easy to grow and reach maturity after 60-70 days
-peas self fertilize, but can be cross fertilized, permitting gene control

Question 16

What does the monohybrid experiment determine?

Answer 16

The principle of segregation and the principle of dominance

Question 17

Decribe the monohybrid experiment

Answer 17

-homozygous with opposite alleles are bred
-a heterozygous is produced and then self-fertilized, where the offsprings have a 3:1 ratio

Question 18

What is a reciprocal cross

Answer 18

When you breed the same genotypes but with different sexes
In autosomal genes, it should give the same thing, but should change for sex-linked

Question 19

What is the evidence gained from the monohybrid cross

Answer 19

-even if the first generation only had purple flowers, the white flowers reappear in the second generation, thus whit was hidden but not lost
-since white is present in the second generation, it means that both alleles were present in the first generation, thus did seperate during meiosis

Question 20

What is simple dominance

Answer 20

When one allele of a gene completely hides the expression of the second allele

Question 21

How to find the genotype of dominant phenotype

Answer 21

Cross it with a homozygous recessive

Question 22

How do you make a prediction in genetics?

Answer 22

You do a punett square

Question 23

What is mendels model of inheritance

Answer 23

-each trait is controlled by one gene
-each gene only has two alleles
-there is a clear dom-res relationship between the two