Study your flashcards anywhere!

Download the official Cram app for free >

  • Shuffle
    Toggle On
    Toggle Off
  • Alphabetize
    Toggle On
    Toggle Off
  • Front First
    Toggle On
    Toggle Off
  • Both Sides
    Toggle On
    Toggle Off
  • Read
    Toggle On
    Toggle Off

How to study your flashcards.

Right/Left arrow keys: Navigate between flashcards.right arrow keyleft arrow key

Up/Down arrow keys: Flip the card between the front and back.down keyup key

H key: Show hint (3rd side).h key

A key: Read text to speech.a key


Play button


Play button




Click to flip

50 Cards in this Set

  • Front
  • Back
binary fission
bacterial reproduction into two daughter cells without the utilization of a mitotic spindle
haploid sex cell; the egg or a sperm that join during fertilization to form a zygote
male sex cell with three distinct parts at maturity: head, middle piece, and tail
diploid cell formed by the union of sperm and egg; the product of fertilization
structure in the ovary that produces the egg and, in particular, the female sex hormones, estrogen and progersterone
release of a secondary oocyte from the ovary; if fertilization occurs, the secondary oocyte becomes an egg
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
male gonad that produces sperm and the male sex hormones
seminiferous tubule
highly coiled duct within the male testes that produces and transports sperm
division of the cytoplasm following mitosis and meiosis
production of an egg in females by the process of meiosis and maturation
cap at the anterior end of a sperm that partially covers the nucleus and contains enzmes that help the sperm penetrate the egg
union of a sperm nucleus and an egg nucleus, which creates the zygote with the diploid number of chromosomes
haploid number of chromosomes
half the diploid number; the number characteristic of gametes that contain only one set of chromosomes
diploid number of chromosomes
twice the number of chromosomes found in gametes
somatic cell
a body cell; excludes cells that undergo meiosis and become a sperm of egg
homologous chromosome
similarly constructed chromosomes with the same shape and that contain genes for the same traits; also called homologues
dominant allele
allele that exerts its phenotypic eggect in the herterozygote; it maskes the expression of the recessive allele
recessive allele
hereditary factor that expresses itself in the phenotype only when the genotype is homozygous
punnet square
gridlike device used to calculate the expected results of simple genetic crosses
individual that is herterozygous for one trait; shows the phenotype of the dominant allele but carries the recessive allele
chemical stored at the ends of axons that is responsible for transmission across a synapse
part of a neuron that sends signals toward the cell body
cell body
portion of a neuron that contains a nucleus and from which dendrites and an axon extend
positive feedback
mechanism of homeostatic response in which the output intensifies and increases the likelihood of response, instead of counterin it and canceling it
new viruses bud from the cell surface
chemical signal produced in one part of the body that controls the activity of other parts
sister chromatids
one of two genetically identical chromosomal units that are the result of DNA replication and are attached to each other at the centromere
constricted region of a chromosome where sister chromatids are attached to one another and where the chromosome attaches to a spindle fiber
stages of the cell cycle (G, S1, G2) durind which growth and DNA synthesis occur when the nucleus is not actively dividing
mitotic phase during which chromosomes are aligned in the middle
mitotic phase durind which chromatin condenses so that chromosomes appear; chromosomes are scattered
mitotic phase during which daughter chromosomes move toward the poles of the spindle
mitotic phase during which daughter cells are located at each pole
type of cell division in which daughter cells receive the exact chromosome and genetic makeup of the parent cell; occurs during growth and repair
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
production of sperm in males by the process of meiosis and maturation
cleavage furrow
indentation that begins the process of cleavage, by which animal cells undergo cytokenesis
cell plate
structure that precedes the formation of the cell wall as a part of cytokinesis in plant cells
chromosomes arranged by pairs according to their size, shape, and general appearance in mitotic metaphase
trisomy 21
one more 21st chromosome
having identical alleles (AA or aa) for a given trait; pure breeding
having two different alleles (Aa) for a given trait
dihybrid cross
individual that is heretozygous for two traits; shows the phenotype governed by the dominant alleles but carries the recessive alleles
fiber of a neuron that conducts nerve impulses away from the cell body
negative feedback
mechanism of homeostatic response by which the output of a system suppresses of inhibits activity of the system
asexual reproduction
reproduction that occurs without sex
sexual reproduction
reproduction that occurs with sex
benign tumor
a ball of cells that do not spread
malignant tumor
a ball of cells that do spread