Vocabulary Quiz 3

Front 1

binary fission

Back 1

bacterial reproduction into two daughter cells without the utilization of a mitotic spindle

Front 2

gamete

Back 2

haploid sex cell; the egg or a sperm that join during fertilization to form a zygote

Front 3

sperm

Back 3

male sex cell with three distinct parts at maturity: head, middle piece, and tail

Front 4

zygote

Back 4

diploid cell formed by the union of sperm and egg; the product of fertilization

Front 5

follicle

Back 5

structure in the ovary that produces the egg and, in particular, the female sex hormones, estrogen and progersterone

Front 6

ovulation

Back 6

release of a secondary oocyte from the ovary; if fertilization occurs, the secondary oocyte becomes an egg

Front 7

ovary

Back 7

in animals, the female gonad, the organ that produces eggs, estrogen, and progesterone; in flowering plants the base of the pistil that protects ovules and, along with associated tissues, becomes a fruit

Front 8

testis

Back 8

male gonad that produces sperm and the male sex hormones

Front 9

seminiferous tubule

Back 9

highly coiled duct within the male testes that produces and transports sperm

Front 10

cytokenesis

Back 10

division of the cytoplasm following mitosis and meiosis

Front 11

oogenesis

Back 11

production of an egg in females by the process of meiosis and maturation

Front 12

acrosome

Back 12

cap at the anterior end of a sperm that partially covers the nucleus and contains enzmes that help the sperm penetrate the egg

Front 13

fertilization

Back 13

union of a sperm nucleus and an egg nucleus, which creates the zygote with the diploid number of chromosomes

Front 14

haploid number of chromosomes

Back 14

half the diploid number; the number characteristic of gametes that contain only one set of chromosomes

Front 15

diploid number of chromosomes

Back 15

twice the number of chromosomes found in gametes

Front 16

somatic cell

Back 16

a body cell; excludes cells that undergo meiosis and become a sperm of egg

Front 17

homologous chromosome

Back 17

similarly constructed chromosomes with the same shape and that contain genes for the same traits; also called homologues

Front 18

dominant allele

Back 18

allele that exerts its phenotypic eggect in the herterozygote; it maskes the expression of the recessive allele

Front 19

recessive allele

Back 19

hereditary factor that expresses itself in the phenotype only when the genotype is homozygous

Front 20

punnet square

Back 20

gridlike device used to calculate the expected results of simple genetic crosses

Front 21

monohybrid

Back 21

individual that is herterozygous for one trait; shows the phenotype of the dominant allele but carries the recessive allele

Front 22

neurotransmitter

Back 22

chemical stored at the ends of axons that is responsible for transmission across a synapse

Front 23

dendrite

Back 23

part of a neuron that sends signals toward the cell body

Front 24

cell body

Back 24

portion of a neuron that contains a nucleus and from which dendrites and an axon extend

Front 25

positive feedback

Back 25

mechanism of homeostatic response in which the output intensifies and increases the likelihood of response, instead of counterin it and canceling it

Front 26

budding

Back 26

new viruses bud from the cell surface

Front 27

hormone

Back 27

chemical signal produced in one part of the body that controls the activity of other parts

Front 28

sister chromatids

Back 28

one of two genetically identical chromosomal units that are the result of DNA replication and are attached to each other at the centromere

Front 29

centromere

Back 29

constricted region of a chromosome where sister chromatids are attached to one another and where the chromosome attaches to a spindle fiber

Front 30

interphase

Back 30

stages of the cell cycle (G, S1, G2) durind which growth and DNA synthesis occur when the nucleus is not actively dividing

Front 31

metaphase

Back 31

mitotic phase during which chromosomes are aligned in the middle

Front 32

prophase

Back 32

mitotic phase durind which chromatin condenses so that chromosomes appear; chromosomes are scattered

Front 33

anaphase

Back 33

mitotic phase during which daughter chromosomes move toward the poles of the spindle

Front 34

telophase

Back 34

mitotic phase during which daughter cells are located at each pole

Front 35

mitosis

Back 35

type of cell division in which daughter cells receive the exact chromosome and genetic makeup of the parent cell; occurs during growth and repair

Front 36

meiosis

Back 36

type of nuclear division that occurs as part of sexual reproduction in which the daughter cells receive the haploid number of chromosomes in varied combinations

Front 37

spermatogenesis

Back 37

production of sperm in males by the process of meiosis and maturation

Front 38

cleavage furrow

Back 38

indentation that begins the process of cleavage, by which animal cells undergo cytokenesis

Front 39

cell plate

Back 39

structure that precedes the formation of the cell wall as a part of cytokinesis in plant cells

Front 40

karyotype

Back 40

chromosomes arranged by pairs according to their size, shape, and general appearance in mitotic metaphase

Front 41

trisomy 21

Back 41

one more 21st chromosome

Front 42

homozygous

Back 42

having identical alleles (AA or aa) for a given trait; pure breeding

Front 43

heterozygous

Back 43

having two different alleles (Aa) for a given trait

Front 44

dihybrid cross

Back 44

individual that is heretozygous for two traits; shows the phenotype governed by the dominant alleles but carries the recessive alleles

Front 45

axon

Back 45

fiber of a neuron that conducts nerve impulses away from the cell body

Front 46

negative feedback

Back 46

mechanism of homeostatic response by which the output of a system suppresses of inhibits activity of the system

Front 47

asexual reproduction

Back 47

reproduction that occurs without sex

Front 48

sexual reproduction

Back 48

reproduction that occurs with sex

Front 49

benign tumor

Back 49

a ball of cells that do not spread

Front 50

malignant tumor

Back 50

a ball of cells that do spread