biology 9

Cell division that produces reproductive cells in sexually reproducing organisms

meosis

prophase

first and longest phase of mitosis, during which the chromosomes become visible and the centrioles separate and take up positions on the opposite sides of the nucleus

metaphase

second phase of mitosis, during which the chromosomes line up across the center of the cell

anaphase

the third phase of mitosis, during which the chromosome pairs separate and move toward opposite poles

telophase

the final stage of mitosis or meiosis, during which a nuclear membrane forms around each set of new chromosomes

Phenotype

physical characteristics of an organism

Genotype

An organism's genetic makeup, or allele combinations.

crossing over

Process in which homologous chromosomes exchange portions of their chromatids during meiosis.

Metaphase I

Paired homologous chromosomes line up across the center of the cell

Anaphase I

Homologous chrmosomes move to the oppisite poles of the cell.

Telophase I

A nuclear membrane forms around each cluster of chromosomes

Interkinesis

Period of time between meiosis I and meiosis II during which no DNA replication takes place.

Metaphase II

Chromosomes line up at the equator.

Anaphase II

sister chromatids separate

Gametes

reproductive cells

nucleus

a part of the cell containing DNA and RNA and responsible for growth and reproduction

dominant genes

the genes that dictate the way a trait is expressed

dominant genes

the genes that dictate the way a trait is expressed

recessive genes

genes that are expressed only in the absence of a dominant gene

Meiosis

Cell division that produces reproductive cells in sexually reproducing organisms

prophase I

Each chromosome comes near its replicated chromosome pair. Nucleus dissolves at this stage. Crossing Over (exchange of genetic material) occurs at this phase.

Prophase II

The first phase of meiosis II. Prophase II is identical to mitotic prophase, except that the number of chromosomes was reduced by half during meiosis I.

Telophase II

Nuclear membrane reforms, cytoplasm divides, 4 daughter cells formed

haploid

An organism or cell having only one complete set of chromosomes.

diploid

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

Zygotes

the diploid product of the fusion of haploid gametes (a fertilized egg).

asexual reproduction

Faster form of reproduction, taking as little as 20 minutes to form a complete offspring.:

asexual reproduction

Offspring inherit all of the same weaknesses as the parent.

asexual reproduction

No time or energy wasted on looking for a mate.

asexual reproduction

Type of reproduction that makes uniform offspring that are all the same

Binary Fission:

When an organism splits into an exact copy

Budding

A small growth on an organism that splits and grows into a new organism.

Regeneration:

When an organism grows back all parts that it lost (like sea stars).

asexual reproduction

Offspring are an identical copy of parent.

sexual reproduction

Two parents produce offspring that are all a bit different from either parent.

sexual reproduction

The joining of male and female sex cells.

External fertilization

like how frogs make tadpoles.:

Pollination

bees carry pollen (plant sperm) from a male flower to a female flower

vegetative propagation

Cutting part of a plant, to make a new identical plant.

sexual reproduction

Offspring with genetic material from 2 parents

sexual reproduction

Requires an egg from a female and a sperm from a male