Exam_4_Study_Guide_Flashcards

Question 1

What are the four reasons for mitosis to occur, and what is the only reason for meiosis to occur?

Answer 1

Mitosis: Growth, Repair, Asexual reproduction, Development. Meiosis: Sexual reproduction.

Question 2

Why is it important for the number of chromosomes to be reduced in meiosis, from 46 to 23?

Answer 2

To ensure that the fertilized egg has the correct diploid number of chromosomes when gametes fuse.

Question 3

Which one produces two identical diploid daughter cells?

Answer 3

Mitosis

Question 4

Which one produces four haploid daughter cells (and each cell is different)?

Answer 4

Meiosis

Question 5

Which one must happen for sexual reproduction?

Answer 5

Meiosis

Question 6

Which one must happen for asexual reproduction?

Answer 6

Mitosis

Question 7

What is happening during metaphase and anaphase of mitosis?

Answer 7

Metaphase: Chromosomes align at the equator. Anaphase: Sister chromatids are pulled apart.

Question 8

What is crossing over, and when does it occur in meiosis?

Answer 8

Crossing over is the exchange of genetic material between homologous chromosomes, occurring during prophase I.

Question 9

What are three major differences between the daughter cells that are produced in mitosis and meiosis?

Answer 9

Mitosis: 2 diploid, identical daughter cells. Meiosis: 4 haploid, genetically different daughter cells.

Question 10

What is a karyotype?

Answer 10

A visual display of an individual’s chromosomes, arranged by size and number.

Question 11

What is non-disjunction?

Answer 11

The failure of chromosomes or chromatids to separate properly during meiosis.

Question 12

What is a trait? What is an allele?

Answer 12

A trait is a characteristic that can be inherited. An allele is a variant form of a gene.

Question 13

What does it mean when we say an allele is dominant? How about recessive?

Answer 13

Dominant allele masks the expression of a recessive allele in a heterozygous individual. Recessive only expresses when homozygous.

Question 14

What does homozygous mean in genetics? How about heterozygous?

Answer 14

Homozygous means having two identical alleles. Heterozygous means having two different alleles.

Question 15

What is genotype? What is phenotype?

Answer 15

Genotype refers to the genetic makeup (allele combination). Phenotype refers to the observable traits.

Question 16

What is meant by homologous chromosomes?

Answer 16

Chromosomes that are similar in shape, size, and genetic content.

Question 17

What percent of their future children would you predict would have six fingers and toes? (Show the Punnett square)

Answer 17

50% (Father: Ff, Mother: ff)

Question 18

Alkaptonuria: Genotypes of Sally, her mother, her father, and her brother?

Answer 18

Sally: Aa, Mother: AA, Father: aa, Brother: aa.

Question 19

Mary is blood type A, her baby is blood type A, what can you conclude about the father’s blood type?

Answer 19

Father must have blood type A.

Question 20

What is the difference between incomplete dominance and codominance?

Answer 20

Incomplete dominance: Neither allele is fully dominant. Codominance: Both alleles are fully expressed.

Question 21

Polygenic inheritance vs. multiple alleles?

Answer 21

Polygenic inheritance: Multiple genes affect a single trait. Multiple alleles: More than two alleles exist for a gene.

Question 22

Color deficiency: From which parent did a man receive the gene?

Answer 22

From his mother, because males inherit X chromosomes from their mothers.

Question 23

Punnett square for color blindness: woman is color blind, man has normal vision

Answer 23

Daughters: 100% carriers (XᴮXᴺ), Sons: 100% color blind (XᴮY).