Chapter 8

Question 1

Cell Reproduction

Answer 1

division of one cell into two daughter cells

Question 2

Reasons for cell reproduction

Answer 2

• cell replacement
• growth
  -reproduction

Question 3

Chromatin

Answer 3

uncondensed chromosomes, made up of histone and DNA

Question 4

Chromosome

Answer 4

Long strands of DNA loosely packed in the nucleus

Question 5

DNA Packing

Answer 5

the process by which a cell’s long DNA molecule is tightly coiled and wrapped around proteins called histones, forming a compact structure called chromatin, allowing it to fit within the small space of the cell nucleus

Question 6

Nucleosome

Answer 6

when chromatin wraps around a histone to form almost a bead on a friendship bracelet.

Question 7

Centromere

Answer 7

the “waist” at which sister chromatids are attached

Question 8

Sister Chromatids

Answer 8

Duplicated chromosomes that are still connected

Question 9

Cell Cycle

Answer 9

Composed of two phases interphase and mitotic

Question 10

Interphase

Answer 10

90% of cell’s life and has three phases: Gap 1, Synthesis phases, Gap 2

Question 11

Gap One

Answer 11

during this time, cells grow, organelles grow in numbers, and everything else functions normally

Question 12

Synthesis Phase

Answer 12

When DNA is replicated

Question 13

Gap Two

Answer 13

Proofreading of DNA, more growth in preparation for cell division

Question 14

Apoptosis

Answer 14

cell-suicide that allows the cell’s parts to be reused

Question 15

Mitosis

Answer 15

the production of two genetically identical daughter cells

Question 16

PMAT

Answer 16

phases of mitosis: prophase, (prometaphase), metaphase, anaphase, telophase

Question 17

Prophase

Answer 17

when sister chromatids condense, the nucleic membrane dissolves, and centrioles start to produce spindle fibers made of microtubules

Question 18

Metaphase

Answer 18

chromosomes align in the middle of cell and the spindle fibers attach to the centromeres (but not al of them)

Question 19

Anaphase

Answer 19

when the spindle fibers start to contract or grow and separates the sister chromatids and pushes the cell apart, creating a cleavage furrow

Question 20

Telophase

Answer 20

nucleic membrane forms to form two daughter nuclei and spindle fibers dissolve, cleavage furrow deepens

Question 21

Cytokinesis

Answer 21

the physical process of cell division, which divides the cytoplasm of a parental cell into two daughter cells

Question 22

Cytokinesis in animal cells

Answer 22

a ring of microfilaments just under the plasma membrane contract, effectively pinching the cell into two

Question 23

Cytokinesis in plant cells

Answer 23

since the cell wall prevents a cleavage furrow, vesicles of cell wall are deposited into the middle and form a cell plate until it connects to the cell wall

Question 24

Cancer

Answer 24

tumors that grow due to mutations that cause unrestricted cell growth

Question 25

Malignant tumor

Answer 25

a tumor that travels from its origin

Question 26

Benign tumor

Answer 26

a tumor that grows in one spot

Question 27

treatments for cancer

Answer 27

chemotherapy, surgery, radiation, drugs

Question 28

Homologues

Answer 28

chromosomes that code for the same trait but different alleles

Question 29

Somatic cells

Answer 29

body cells

Question 30

Germ cells /gametes

Answer 30

reproductive cells

Question 31

Autosomes

Answer 31

homologues that code for something in both genders

Question 32

Sex Chromosomes

Answer 32

XY chromosomes that determine gender (XX=girl, XY=boy)

Question 33

Metastasize

Answer 33

when cancerous cells break away from its origin and spread

Question 34

Karyotype

Answer 34

a visual representation of one's chromosomes in number order

Question 35

Haploids

Answer 35

one full set of chromosomes (n)

Question 36

Diploid

Answer 36

two full sets of chromosomes (2n)

Question 37

Ploidy

Answer 37

the number of sets of chromosomes (xn)

Question 38

Fertilization

Answer 38

when an egg (or female gamete) meets a sperm (or male gamete) and becomes a zygote

Question 39

Zygote

Answer 39

The fertilized egg

Question 40

Meiosis

Answer 40

the reproduction of sex cells

Question 41

Prophase I

Answer 41

Nuclear envelope dissolves and spindle fibers start to form

Question 42

Metaphase I

Answer 42

The homologous pairs align in the middle and spindle fibers attach to the pairs. homologous sister chromatids fuse together with specific gene alignment through special proteins, and crossing over occurs

Question 43

Anaphase I

Answer 43

when the homologous pairs separate

Question 44

Telophase I

Answer 44

chromatids move to poles of the cells and a nuclear envelope form

Question 45

Cytokinesis I

Answer 45

two haploid cells form

Question 46

Meiosis II

Answer 46

Splitting of sister chromatids

Question 47

Prophase II

Answer 47

spindle forms and nuclear envelope forms

Question 48

Metaphase II

Answer 48

Sister chromatids align in the middle and spindle fibers attach

Question 49

Anaphase II

Answer 49

Sister chromatids are separated

Question 50

Telophase II and Cytokinesis II

Answer 50

four new, unique cells form

Question 51

Causes of genetic variation

Answer 51

- independent assortment - cross-over - non-disjunction

Question 52

Independent assortment

Answer 52

how the homologous sister chromatids align during Metaphase I

Question 53

crossing over

Answer 53

when homologous pairs of chromosomes align through special proteins and gene alignment allowing alleles to switch and new genetically unique chromosomes form

Question 54

Nondisjunction

Answer 54

When a sister chromatid or homologous pair doesn't separate during one of the anaphases, causing one extra or less chromosome which can lead to mutations such as Down syndrome

Question 55

Down syndrome

Answer 55

Trisomy 21, three 21st chromosomes that cause stunted growth, and other complications

Question 56

Tetrad

Answer 56

the fused homologous sister chromatids

Question 57

Phenotype

Answer 57

the variation of traits within another trait (genotype) ex//different shades of brown eyes