Mendel

What is heredity?

Passing traits from parents to offspring

What are genes?

Units of heredity found on chromosomes

What is the law of segregation?

Alleles separate so each gamete gets one

What is the law of independent assortment?

Traits are inherited independently of each other

What did Mendel call traits?

Unit characters

Why did Mendel use pea plants?

They have clear, controllable traits

What are discrete traits?

Traits with only two possible forms

What happened in Mendel’s F1 generation?

All offspring showed the dominant trait (all purple)

What is the F2 ratio?

3:1 (dominant:recessive)

What is a dominant trait?

A trait that masks another

What is a recessive trait?

A trait that can be hidden but reappear

What is the law of segregation?

Alleles separate so each gamete gets one

What is haploid vs diploid?

Haploid = 1 set, Diploid = 2 sets

What is incomplete dominance?

A blended phenotype between two alleles

What is codominance?

Both alleles are fully expressed

What are multiple alleles?

More than two forms of a gene

What is a polygenic trait?

A trait controlled by multiple genes

What is epistasis?

One gene affects the expression of another

What is pleiotropy?

One gene affects multiple traits

What is special about blood type genetics?

It shows codominance and multiple alleles

what does polygenic traits produce in a population

continuous variation, bell shaped curve

What is sex linkage?

Traits controlled by genes on sex chromosomes

Which chromosome carries most sex-linked traits?

X chromosome

Which sex is more affected by X-linked disorders?

Males

Why are males more affected?

They only have one X chromosome

Example of a sex-linked disorder?

Color blindness

how is sicke cell anemia developed?

develops when a person inherits two mutated
copies of a gene (one from each parent) that
codes for a subunit of hemoglobin. When oxygen is low, the altered hemoglobin forms
crystal-like structures that push red blood cells into
a sickle shape
• The altered protein differs from the normal protein
by just a single amino acid

blending theory of inheritance

The idea that parental traits mix together in offspring, no recessive genes they just mix and dissapear

cross pollination

The transfer of pollen between different plants

true breeding

Producing identical offspring for a trait

What is the P generation?

The original true-breeding parents

What is the F1 generation?

Offspring of the P generation

How is the F2 generation produced?

By self-pollinating F1 individuals

What is homozygous?

Two identical alleles

What is heterozygous?

Two different alleles

What is genotype?

Genetic makeup

What is phenotype?

Physical appearance

What is a monohybrid cross?

A cross between two heterozygotes

When do you use the product rule?

For independent events happening together

When do you use the sum rule?

When multiple ways can produce the same outcome (dependent)

What is a testcross?

Crossing with a homozygous recessive to determine genotype

What ratio indicates heterozygous in a testcross?

1:1

What is a dihybrid cross ratio?

9:3:3:1

What is a locus?

Location of a gene on a chromosome

What type of inheritance is blood type?

Codominance and multiple alleles

dihybird

is an organism that is heterozygous for TWO different genes

QTLs

genes that contribute to polygenic traits (Quantitative Trait Loci)