Chapter 8 (The Cellular Basis Of Reproduction And Inheritance)

Front 1

What is cell division?

Back 1

- reproduction of a cell through duplication of the genome and division of the cytoplasm.

Front 2

What are chromosomes?

Back 2

- threadlike, gene carrying structure found in the nucleus of a eukaryotic cell and most visible during mitosis and meiosis
- main gene carrying structure of a prokaryotic cell
- consists of 1 very long piece of chromatin; combination of DNA and protein

Front 3

What is asexual reproduction?

Back 3

creation of genetically identical offspring by a single parent, without the participation of sperm and egg

Front 4

- in the amoeba it does reproduction
- in the body it does development, growth, and repair

Back 4

What function does cell division play in amoeba? What function does it play in your body?

Front 5

What is binary fission?

Back 5

means of asexual reproduction in which a parent organism, often a single cell, divides into 2 gentically identical individuals of about equal size.

Front 6

because the genetically identical offspring inherit their DNA from a single parent.

Back 6

Why is binary fission classified as asexual reproduction.

Front 7

What are sister chromatids?

Back 7

- 1 of the 2 identical parts of a duplicated chromosome in a Eukaryotic cell.
- prior to mitosis, they remain attached to each another at the centromere

Front 8

What is a centromere?

Back 8

- region of a duplicated chromosome where 2 sister chromatids are joined and where spindle microtubules attach during meiosis and mitosis
- divison at the onset of anaphase during mitosis and anaphase 2 during meiosis.

Front 9

- when the cell is preparing to divide and has duplicated its chromosomes, but before the duplicate actually separate.

Back 9

When does a chromosome consist of 2 identical chromatids?

Front 10

What is cell cycle?

Back 10

ordered sequence of events (including the interphase and the mitotic phase) that extends from the time a eukaryotic cell is first formed from a dividing parent until its own division into 2 cells.

Front 11

What is interphase?

Back 11

- period in the eukaryotic cell cycle when the cell is not actually dividing.
- constitutes the majority of the time spent in the cell cycle

Front 12

What is the mitotic phase?

Back 12

- part of the cell cycle when the nucleus divides (via mitosis), its chromosomes are distributed to the daughter nuclei, and the cytoplasm divides (via cytokineses), producing 2 daughter cells

Front 13

What is mitosis?

Back 13

- divison of a single nucleus into 2 genetically identical nuclei
- this and cytokinesis make up the mitotic (M) phase of the cell cycle.

Front 14

What is cytokinesis?

Back 14

- division of the cytoplasm to form 2 separate daughter cells
- usually occurs in conjunction with telophase of mitosis
- this and mitosis make up the mitotic (M) phase of the cell cycle

Front 15

What are the 5 stages of mitosis?

Back 15

- Prophase
- Prometaphase
- Metaphase
- Anaphase
- Telophase

Front 16

What is prophase?

Back 16

first stage of mitosis, during which the chromatin condenses to form strucutres (sister chromatoids) visible with a light microscope and the mitotic spindle begins to form, but the nucleus is still in tact

Front 17

What is prometaphase?

Back 17

- second stage of mitosis, during which the nuclear envelope fragments and the spindle microtubules attach to the kinetochores of the sister chromatoids

Front 18

What is the metaphase?

Back 18

- third stage of mitosis, during which all the cell's duplicated chromososmes are lined up at an imaginary plane equidistant between the poles of the mitotic spindle

Front 19

What is the anaphase?

Back 19

- fourth stage of mitosis, beginning when sister chromatoids separate from each other and ending when a complete set arrive at each of the 2 poles of the cell.

Front 20

What is the telophase?

Back 20

- fifth and final stage of mitosis, during which daughter nuclei form at the 2 poles of a cell
- usually occurs together with cytokinesis

Front 21

What is mitotic spindle?

Back 21

- football-shaped structure formed of microtubules, and associated proteins that is involved in the movement of chromosomes during mitosis and meiosis.

Front 22

What are centromeres?

Back 22

- material in the cytoplasm of a Eukaryotic cell that gives rise to microtubules; important in mitosis and meiosis
- aka microtubule organizing center

Front 23

What is a cleavage furrow?

Back 23

- 1st sign of cytokinesis during cell division in an animal cell
- shallow groove in the cell surface near the old metaphase plate

Front 24

What is cell plate?

Back 24

double membrane across the midline of a dividing plant cell, between which the new wall forms during cytokinesis.

Front 25

- in animals, cytokinesis involves a cleavage furrow in which the contractuary microfilaments pinch the cells in two.
- in plants, it involves formation of a cell plate, a fusion of vesicles that forms new plasma membranes and new cell walls between the cells

Back 25

What is the difference in cytokineses between plant and animal cells?

Front 26

What is growth factor?

Back 26

protein secreted by certain body cells that stimulates other cells to divide

Front 27

What is density-dependent inhibition?

Back 27

- ceasing of cell divison that occurs when cells touch one another

Front 28

What is anchorage dependence?

Back 28

requirement that to divide, a cell must be attach to a solid surface

Front 29

What is cell cycle control system?

Back 29

cyclically operating set of proteins that triggers and coordinate events in the eukaryotic cell cycle

Front 30

What is a tumor?

Back 30

abnormal mass of rapidly growing cells that forms within otherwise normal tissue

Front 31

What is a benign tumor?

Back 31

abnormal mass of cells that remains at its orginal site in the body

Front 32

What is a malignant tumor?

Back 32

- abnormal tissue mass that can spread into neighboring tissue and to other parts of the body
- cancerous tumor

Front 33

What is cancer?

Back 33

disease characterized by the presence of malignant tumors (rapidly growing and spreading of abnormal body cells) in the body

Front 34

What is metastasis?

Back 34

spread of cancer cells beyond their original site

Front 35

What is carcinomas?

Back 35

cancer that originates in the coverings of the body, such as skin or the lining of the intestinal tract

Front 36

What are sarcomas?

Back 36

cancer of the supportive tissues, such as bone, cartillage, and muscle

Front 37

What is leukemia?

Back 37

- type of cancer of the blood forming tissues, characterized by an excessive production of white blood cells and an abnormally high number of them in the blood

Front 38

What is lymphocytes?

Back 38

- type of white blood cell that is chiefly responsible for the acquired immune response and is found mostly in the lymphatic system
EX: b-cell, t-cell

Front 39

What is a somatic cell?

Back 39

any cell in a multicellular organism except a sperm/egg or a cell that develops into sperm/egg

Front 40

What is homologus chromosome?

Back 40

- two chromosomes that make up a matched pair in a diploid cell
- are of the same length, centromere position, and and staining pattern and posesses genes for the same characteristic at corresponding loci
- one inherited from the father, the other is from the mother

Front 41

What is locus?

Back 41

- particular site whre a gene is found on a chromosome
- have corresponding gene loci

Front 42

What are sex chromosomes?

Back 42

chromosome that determines whether an individiual is a male or female

Front 43

What are autosomes?

Back 43

- chromosome not directly involved in determining the sex of an organism
EX: any chromosome other than X and Y

Front 44

What is life cycle?

Back 44

entire sequence of stages in the life of an organism, from the adults of 1 generation to the adults of the next

Front 45

What is a diploid?

Back 45

- orgnaism that reproduces sexually, a cell containing two homologous sets of chromosomes, one set inherited from each parent

Front 46

What are gametes?

Back 46

- sex cell; haploid egg/sperm
- union of two of these of opposite sex (fertilization) produces a zygote

Front 47

What is fertilization?

Back 47

union of the nucleus of a sperm cell with nucleus of an egg cell, producing a zygote

Front 48

What is zygote?

Back 48

diploid fertizlized egg, which results from the union of the sperm and egg cell nucleus

Front 49

What is meiosis?

Back 49

- in a sexually reproducing organism, the divison of a single diploid nuclues into 4 haploid daughter nuclei
- this and cytokinesis produce haploid gamets from diploid cells in the reproductive organs of the parents

Front 50

What are tetrads?

Back 50

- paired set of homologous chromosomes, each composed of two sister chromatids
- some may form during prophase 1 of meiosis, when crossing over may occur

Front 51

What is a chiasma?

Back 51

microscopically, visible iste where crossing over has occured between chromatids of homologous chromosomes during prophase 1 of meiosis

Front 52

What does crossing over mean?

Back 52

- exchange of segments between chromatids of homologus chromosomes during synapsis in prophase 1 of meiosis
- also the exchange of segments between DNA molecules in prokaryotes

Front 53

What is genetic recombination?

Back 53

- production, by crossing over and or interdependent assortment of chromosomes during meiosis, of offspring with allele combinations different from those in the parents
- the term may also be used more specifically to mean the production by crossing over of eukarytoic or prokaryotic chromosomes with gene combinations different from those in the original chromosome

Front 54

What is a karyotype?

Back 54

- display of micrographs of the metaphase chromomes of a cell, arranged by size and centromere position
- used to identify certain chromosomal abnormalities

Front 55

What is down syndrome?

Back 55

- human genetic disorder resulting from the presence of an extra chromsome 21.
- chracterized by heart and respiartorial defects and varying degrees of mental retardation

Front 56

What is nondisjunction?

Back 56

- accident of meiosis or mitosis in which a piar of homologous chromosomes or a pair of sister chromatids fail to separate at anaphase

Front 57

diploid gamete would result if the nondisjunction affects all the chromosomes during one of the miotic division.

Back 57

How could nondisjunction result in diploid gamete?

Front 58

What is a polyploid organism?

Back 58

1 with more than 2 sets of homologous chromosomes in its body cells

Front 59

What is deletion?

Back 59

- loss of 1 or more nucleotides from a gene by mutation
- loss of a fragment of a chromosome

Front 60

What is duplication?

Back 60

- repetition of part of a chromosome resutling from fusion with a fragment from a homologous chromosome
- result from an error in meiosis or from mutagenesis

Front 61

What is inversion?

Back 61

- change in a chromosome resulting from reattachment of a chromosme fragment to the original chromosome, but in a reverse direction
- mutagens and erros during meiosis can cause these

Front 62

What is translocation?

Back 62

- during protein synthesis, the movement of tRNA molecule carrying a growing polypeptide chain from the A site tot he P site on a ribosome
- change in a chromosome resulting from a chromosomal fragment attach to a nonhomologous
= can result of an error in meiosis or from mutagenesis

Front 63

- reciprical translocation swaps chromosome segments between nonhomologous chromosome
- crossing over normally exchangers corresponding segments between homologus chromosmes

Back 63

How is recipricol translocation different from normal crossing over?