Unit 5

Question 1

What is the study of heredity and hereditary variation called?

Answer 1

Genetics

Genetics encompasses the mechanisms and processes that govern the inheritance of traits.

Question 2

Define heredity.

Answer 2

The transmission of traits from one generation to the next

Heredity explains how characteristics are passed down through generations.

Question 3

How are traits passed from parent to offspring?

Answer 3

Through genes

Genes are the fundamental units of heredity that carry information for specific traits.

Question 4

What are segments of DNA that code for basic units of heredity called?

Answer 4

Genes

Genes are responsible for the inheritance of specific traits and characteristics.

Question 5

How do offspring acquire genes from their parents?

Answer 5

By inheriting chromosomes

Chromosomes are structures that contain genes and are passed from parents to offspring during reproduction.

Question 6

What type of reproduction involves a single individual?

Answer 6

Asexual reproduction

Asexual reproduction does not require the fusion of gametes.

Question 7

In asexual reproduction, what is the only source of variation?

Answer 7

Mutations

Offspring are clones, being exact copies of the parent.

Question 8

How do organisms reproduce asexually?

Answer 8

Through mitosis

Mitosis allows for the generation of clones.

Question 9

What type of reproduction involves two parents?

Answer 9

Sexual reproduction

Sexual reproduction involves male and female gametes.

Question 10

What is a key characteristic of offspring produced through sexual reproduction?

Answer 10

Unique combinations of genes

Offspring are genetically varied from both parents and siblings.

Question 11

True or False: In sexual reproduction, offspring are clones of the parents.

Answer 11

False

Offspring from sexual reproduction are genetically unique.

Question 12

What are homologous chromosomes?

Answer 12

A pair of chromosomes that carry the same genetic information

They are the same size, length, and have the same centromere position.

Question 13

How many homologous chromosomes does each individual inherit?

Answer 13

Two homologous chromosomes, one from each parent

One homologous chromosome is inherited from mom and one from dad.

Question 14

True or False: Homologous chromosomes have different genetic information.

Answer 14

False

Homologous chromosomes carry the same genetic information.

Question 15

Fill in the blank: Homologous chromosomes are characterized by having the same _______.

Answer 15

genetic information

They also have the same size, length, and centromere position.

Question 16

What is inherited from the mother in terms of homologous chromosomes?

Answer 16

One homologous chromosome

The other homologous chromosome is inherited from the father.

Question 17

What is inherited from the father in terms of homologous chromosomes?

Answer 17

One homologous chromosome

The other homologous chromosome is inherited from the mother.

Question 18

What is the centromere?

Answer 18

Specific area of chromosome where the chromatids attach

The centromere plays a crucial role during cell division.

Question 19

What is the kinetochore?

Answer 19

The protein complex that assembles at the centromere

The kinetochore is essential for the movement of chromosomes during cell division.

Question 20

What are spindle fibers?

Answer 20

Structures that help separate chromosomes during cell division

Spindle fibers are formed from microtubules and play a key role in mitosis and meiosis.

Question 21

Close up image of chromosome

Answer 21

Question 22

What’s a karyotype of chromosome?

Answer 22

A display of chromosome pairs ordered by size and length

Question 23

What type of cells are somatic (body) cells?

Answer 23

Autosomes

Somatic cells make up most of the body tissues and organs.

Question 24

What does diploid (2n) mean?

Answer 24

Two complete sets of each chromosome

Question 25

What is the diploid number of chromosomes in humans?

Answer 25

2n = 46 ## Footnote This includes all autosomes.

Question 26

What are gametic cells?

Answer 26

Sex cells ## Footnote Gametic cells include sperm and eggs.

Question 27

What does haploid (n) mean?

Answer 27

One set of each chromosome ## Footnote Haploid cells contain half the number of chromosomes.

Question 28

What is the haploid number of chromosomes in humans?

Answer 28

n = 23 ## Footnote This is the number of chromosomes in human sperm and eggs.

Question 29

What are the two types of chromosomes?

Answer 29

Autosomes: chromosomes that don’t determine the sex Sex Chromosomes: X and Y Eggs: X (humans: 22+X) Sperm: X or Y (humans: 22+X or 22+Y)

Question 30

What’s is commons in all sexually reproducing organisms regarding the amount of diploids and haploids?

Answer 30

Both have a diploid and haploid number

Question 31

Define life cycle

Answer 31

Sequence of stages in the reproductive history of an organism from conception to its own reproduction

Question 32

What alternates in sexual life cycles?

Answer 32

Fertilization and meiosis

Question 33

Define fertilization

Answer 33

When a sperm cell (haploid) fuses with an egg (haploid) to form a zygote (diploid)

Question 34

What is meiosis?

Answer 34

A process that creates haploid gamete cells in sexually reproducing diploid organisms ## Footnote Meiosis is essential for sexual reproduction.

Question 35

What is the result of meiosis in terms of chromosome number?

Answer 35

Daughter cells with half the number of chromosomes as the parent cell ## Footnote This reduction is crucial for maintaining the species' chromosome number through generations.

Question 36

What is the diploid chromosome number in humans?

Answer 36

2n = 46 ## Footnote This means humans have 46 chromosomes in their somatic (body) cells.

Question 37

What type of cells does meiosis produce?

Answer 37

Sperm and eggs that are haploid: n = 23 ## Footnote Haploid cells contain only one set of chromosomes.

Question 38

How many rounds of division are involved in meiosis?

Answer 38

Two rounds of division ## Footnote These rounds are referred to as Meiosis I and Meiosis II.

Question 39

What is the significance of producing haploid gametes?

Answer 39

It allows for genetic diversity and maintains chromosome number upon fertilization ## Footnote When two haploid gametes fuse during fertilization, they form a diploid zygote.

Question 40

Fill in the blank: Meiosis produces _______ gamete cells.

Answer 40

haploid ## Footnote Haploid cells are essential for sexual reproduction.

Question 41

True or False: Meiosis results in daughter cells that are diploid.

Answer 41

False ## Footnote Meiosis results in haploid daughter cells.

Question 42

What type of cells does meiosis occur in?

Answer 42

Gametes (sperm/egg) ## Footnote Meiosis is specifically involved in the formation of reproductive cells.

Question 43

How many divisions occur during meiosis?

Answer 43

2 divisions ## Footnote Meiosis consists of two rounds of cell division.

Question 44

What is the result of meiosis in terms of daughter cells?

Answer 44

4 haploid daughter cells ## Footnote Haploid cells contain half the number of chromosomes.

Question 45

What type of cells does mitosis occur in?

Answer 45

Somatic cells ## Footnote Mitosis is responsible for growth and repair in the non-reproductive cells.

Question 46

How many divisions occur during mitosis?

Answer 46

1 division ## Footnote Mitosis involves a single round of division to produce daughter cells.

Question 47

What is the result of mitosis in terms of daughter cells?

Answer 47

2 diploid daughter cells ## Footnote Diploid cells have a full set of chromosomes.

Question 48

Are daughter cells genetically identical in mitosis?

Answer 48

Yes ## Footnote Mitosis produces genetically identical daughter cells.

Question 49

Are daughter cells genetically identical in meiosis?

Answer 49

No, they are genetically unique ## Footnote Meiosis results in genetic variation among daughter cells.

Question 50

What happens in prophase 1 of meiosis 1?

Answer 50

Question 51

What happens in metaphase 1 and anaphase 1 of meiosis 1?

Answer 51

The image for anaphase is incorrect and the membrane should not be pinching in

Question 52

What is telophase 1 and cytokinesis in meiosis 1?

Answer 52

Note in telophase the membrane starts pinching in

Question 53

What’s happens in prophase 2 in meiosis 2?

Answer 53

Question 54

What’s happens in metaphase 2 in meiosis 2?

Answer 54

Question 55

What’s happens in anaphase 2 in meiosis 2?

Answer 55

Note the membrane DOES NOT start pinching yet

Question 56

What’s happens in telophase 2 and cytokinesis in meiosis 2?

Answer 56

Note the membrane starts pinching in in telophase 2

Question 57

What are the three ways Meiosis leads to genetic variation and how do they?

Answer 57

1. Crossing over which produces recombinant chromosomes: they exchange genetic material 2. Independent assortment of chromosomes where chromosomes are randomly oriented along the metaphase plate during metaphase 1. (Each can orient with either the maternal or paternal chromosomes closer to the given pole) 3. Random fertilization: any sperm can fertilize the egg

Question 58

What process ensures genetic diversity in sexually reproducing organisms?

Answer 58

Meiosis followed by fertilization ## Footnote This process provides genetic variation that plays a role in natural selection.

Question 59

What role does genetic variation play in evolution?

Answer 59

It plays a role in natural selection ## Footnote Genetic variation allows populations to adapt to changing environments.

Question 60

What drives the cellular process of meiosis?

Answer 60

The interaction of subcellular components and free energy ## Footnote Free energy is required for the growth and reproduction of living systems.

Question 61

Fill in the blank: _______ followed by fertilization ensures genetic diversity.

Answer 61

[Meiosis]

Question 62

True or False: Meiosis is not essential for genetic variation in sexually reproducing organisms.

Answer 62

False

Question 63

What is required for the growth and reproduction of living systems?

Answer 63

Free energy ## Footnote Free energy is necessary for various cellular processes, including meiosis.