Meiosis and Inheritance

Question 1

What does a circle vs. square, shaded vs. non shaded in a pedigree mean?

Answer 1

Circle = Female
Square = Male

Shaded = Affected

Question 2

What is a gene vs. an allele?

Answer 2

A gene is… a section of DNA that codes for a protein

While an allele is… version of a gene caused by mutation and are @ same place on a chromosome.

Question 3

What is the difference between genotype and phenotype?

Answer 3

Genotype: Genetic makeup
ie) a mutated gene

Phenotype: Physical traits
ie) having LFS

Question 4

What does it mean to be homozygous vs. heterozygous?

Answer 4

homozygous: same version of same gene

heterozygous? different version of same gene

Question 5

chromatid vs sister chromatids

Answer 5

Chromatid: 1/2 of a chromosome

Sister chromatids: two identical chromatids that make up a chromosome

Question 6

What are gametes?

Answer 6

Genetically unique reproductive cells

X chromosome = egg
Y chromosome = sperm

Question 7

How are gametes made?

Answer 7

During meiosis

Question 8

How do gametes end up with only half the amount of genetic information of all other body cells?

Answer 8

Meiosis contains two rounds of cell division without DNA replication in between. This process reduces the number of chromosomes by half.

Question 9

Explain 2 processes that happen during meiosis that ensure all gametes are genetically unique?

Answer 9

Crossing over and mutation during DNA replication

Question 10

How does meiosis make offspring that are genetically similar/different from their parents?

Answer 10

23 chromosomes from each parent join together to create 46 chromosome cell

variations may occur in each chromosome from each parent, creating some genetic differences

Question 11

homologous chromosomes

Answer 11

pair of chromosomes with similar, not identical, genes