Bio Test - Unit 4 - Definitions

Front 1

sexual reproduction

Back 1

reproduction involving the union of gametes.

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asexual reproduction

Back 2

reproduction, as budding, fission, or spore formation, not involving theunion of gametes.

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binary fission

Back 3

("division in half") is a kind of asexual reproduction. It is the most common form of reproduction in prokaryotes and occurs in some single-celled eukaryotes like Amoeba and Paramecium.

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cell reproduction

Back 4

is used as a means of reproduction in organisms that reproduce asexually, as by fission or spore formation, and sexually reproducing organisms form gametes through cell division

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genetics

Back 5

the study of heredity and the variation of inherited characteristics.

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heredity

Back 6

the passing on of physical or mental characteristics genetically from one generation to another.

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variation

Back 7

any difference between cells, individual organisms, or groups of organisms of any species caused either by genetic differences (genotypicvariation) or by the effect of environmental factors on the expression of the genetic potentials (phenotypic variation)

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DNA

Back 8

deoxyribonucleic acid, a self-replicating material present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information.

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gene

Back 9

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.

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chromosome

Back 10

a threadlike structure of nucleic acids and protein found in the nucleus of most living cells, carrying genetic information in the form of genes.

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genome

Back 11

genetic material of an organism

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gene pool

Back 12

the collection of genes in an interbreeding population that includes each gene at a certain frequency in relation to its alleles

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gamete

Back 13

the cells used during sexual reproduction to produce a new individual organism or zygote

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somatic cell

Back 14

any cell of a living organism other than the reproductive cells.

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karyotype

Back 15

the number and visual appearance of the chromosomes in the cell nuclei of an organism or species.

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homologous chromosomes

Back 16

chromosome pairs, one from each parent, that are similar in length, gene position, and centromere location. The position of the genes on eachhomologous chromosome is the same, however the genes may contain different alleles.

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autosome

Back 17

any chromosome that is not a sex chromosome.

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sex chromosome

Back 18

a chromosome involved with determining the sex of an organism, typically one of two kinds.

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meiosis

Back 19

a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores.

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haploid

Back 20

having a single set of unpaired chromosomes.

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diploid

Back 21

containing two complete sets of chromosomes, one from each parent.

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meiosis 1 and 2

Back 22

which four daughter cells that have the haploid chromosome number (23 in humans) are formed. As in mitosis (somatic cell division), meiosis I and II are each divided into four phases: prophase, metaphase, anaphase, and telophase.

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crossing over

Back 23

occurs between prophase 1 and metaphase 1 and is the process where homologous chromosomes pair up with each other and exchange different segments of their genetic material to form recombinant chromosomes.

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tetrad

Back 24

a group or set of four.

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independent assortment

Back 25

formation of random combinations of chromosomes in meiosis and of genes on different pairs of homologous chromosomes

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random fertilization

Back 26

the concept that alleles are separate from each other when characteristics are being passed down

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genetic recombination

Back 27

the production of offspring with combinations of traits that differ from those found in either parent

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trisomy 21

Back 28

the most common form of Down syndrome, caused by an extra copy of chromosome number 21.

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nondisjunction

Back 29

the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal distribution of chromosomes in the daughter nuclei.

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klinefelter syndrome

Back 30

is a genetic disorder that affects males. Klinefelter syndrome occurs when a boy is born with one or more extra X chromosomes. Most males have one Y and one X chromosome. Having extra X chromosomes can cause a male to have some physical traits unusual for males.

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metafemale

Back 31

is a low viability Drosophila fruit fly with a female phenotype in which the ratio of X chromosomes to sets of autosomes (A) exceeds 1.0.

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turner syndrome

Back 32

is a chromosomal condition that alters development in females. Women with this condition tend to be shorter than average and are usually unable to conceive a child (infertile) because of an absence of ovarian function.

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apoptosis

Back 33

the death of cells that occurs as a normal or controlled part of an organism's growth or development

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angiogenesis

Back 34

process in which new blood vessels form from pre existing vessels

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protoncogene

Back 35

regulate cell cycle, code for proteins that increase the rate of cell cycle during periods or growth or wound healing or pregnancy

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oncogene

Back 36

a mutated proto oncogene that upregulates cell division more than normal

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tumor suppressor gene

Back 37

code for proteins that act at the three checkpoints and stop the cell cycle if dna damage is detected

Front 38

what kind of dna mutations may be involved in cancer

Back 38

- mutated protooncogenes

- tumor suppresor genes

- dna repair enzymes

- genes involved in apoptosis

- genes that increase angiogenesis

- genes that regulate the immune response

Front 39

describe how p53 prevents cancer cells

Back 39

stopping cell division at G1, immune systems role, natural killer WBCs specific to kill cancer