Meiosis and Genetics

Question 1

What occurs during Prophase 1

Answer 1

The chromosomes condense and the nuclear envelope breaks down.

Question 2

What occurs during Prophase 2

Answer 2

A new spindle forms around the chromosomes.

Question 3

What occurs during Metaphase 1

Answer 3

Pairs of homologous chromosomes meet at the equator of the cell.

Question 4

What occurs during Metaphase 2

Answer 4

Chromosomes line up at the equator.

Question 5

What occurs during Anaphase 1

Answer 5

Homologous chromosomes move to the opposite poles of the cell.

Question 6

What occurs during Anaphase 2

Answer 6

Centromeres divide, chromatids move to opposite poles of the cell.

Question 7

What occurs during Telophase 1

Answer 7

Chromosomes gather at the poles of the cells and the cytoplasm seperates.

Question 8

What occurs during Telophase 2

Answer 8

A new nuclear envelope forms around the chromaids, and the cytoplasm seperates.

Question 9

Describe crossing over

Answer 9

During prophase 1, homologous chromosomes pair up to form a tetrad. Bits of non-sister chromatids are swapped at “random” locations. Crossing over creates more combinations of DNA than would otherwise be possible

Question 10

Describe independent assortment

Answer 10

During metaphase 1, homologous chromosomes line up together across the middle. Then, they are randomly sorted into different cells

Question 11

Describe random fertilization

Answer 11

What is the probability that any one sperm will fertilize any particular egg? 1 out of 64 trillion.

Question 12

Compare/Contrast Mitosis vs Meiosis

Answer 12

Mitosis: Growth, Repair, creates two genetically identical diploid daughter cells.
Meiosis: Sexual Reproduction, creates four genetically different Haploid cells

Question 13

How is genetic information from both parents combined in the fertilized egg to produce a new combination of genes and traits.

Answer 13

Half the genetic information for the offspring comes from the father and the other half comes from the mother, out of all the sperm cells and all the eggs there is a huge variety of the genetic combination that can be shown in the offspring.

Question 14

What is dominant vs recessive

Answer 14

Two “factors” control a trait, one is dominant and the other recessive. For the recessive trait to show both factors must be recessive, often shown by a lower case letter “a” however for the dominant trait to show there only needs to be one because it “dominates” recessive gene often shown with an uppercase letter “A”

Question 15

What is a phenotype

Answer 15

A phenotype is the observable characteristics of an individual resulting from its genotype

Question 16

What is a genotype

Answer 16

A genotype is the genetic makeup of a cell and contributes to its phenotype. Shown by a set of two letters “AA” that represents one of the two alleles in a genotype.

Question 17

What is an allele and what is its function

Answer 17

An allele is one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome. The one that produces the protein is usually the dominant one and the one that doesn’t produce a protein is recessive.

Question 18

What is the law of segregation

Answer 18

The two alleles of the parent separate during meiosis so that each gamete contains only one allele

Question 19

What is incomplete dominance

Answer 19

In complete dominance occurs when the dominant allele doesn’t fully mask the recessive one. So, for example if the color red was dominant for flower petals and white is recessive and there is incomplete dominance than the flower petals would be pink.

Question 20

What is co-dominance

Answer 20

Co-dominance occurs when both Alleles are dominant resulting in a mix of both colors like a speckled chicken shown by two uppercase letters “AB” this occurs because alleles produce the protein.

Question 21

What is multiple allele inheritance

Answer 21

Multiple allele inheritance is a situation where a gene is controlled by more than two allele Ex: Blood type (A, B, AB, and O) from 3 alleles (i, Ia, Ib)

Question 22

What is a polygenic trait

Answer 22

trait controlled by more than one gene, often deals with size, shape, form , color. For example in skin color each dominant allele makes melanin and darkens the skin by a certain amount.

Question 23

Compare/Contrast Polygenic inheritance and single gene inheritance

Answer 23

Polygenic inheritance results from multiple alleles and has a wide variety of phenotypes. Single gene inheritance results from one set of alleles and usually only has two outcomes

Question 24

How to you show someone who is affects by a trait on a pedigree

Answer 24

A shaded shape

Question 25

How to show a female on a pedigree

Answer 25

A circle

Question 26

How to show a male on a pedigree

Answer 26

A square

Question 27

How to show someone who we don’t know the sex of

Answer 27

A diamond

Question 28

How do you know if a trait is sex linked or autosomal

Answer 28

If the trait shows on both males and females or only males.

Question 29

What is the difference between sex and autosomal chromosomes

Answer 29

And autosomal chromosome in one of the 22 non sex chromosomes. The sex chromosomes dictate the sex of the offspring XY for males XX for females. The males sperm dictates the sex of the offspring.