chapter 4 science terms

Nucleus

organelle that controls all the activities of a cell and contains hereditary materials made of proteins and DNA.

Mitosis

cell process in which the nucleus divides to form 2 nuclei identical to each other and identical to the original nucleus in a series of steps prophase metaphase anaphase telephase.

Asexual reproduction

is a type of reproduction fission budding and regeneration in which a new organism is produced from one organism and has DNA identical to the parent organism.

chromosome

structure in a cell's nucleus that contains hereditary material.

Organism

any living thing that uses energy is made of cells, reproduction responds, grows and develops.

Sexual reproduction

is a type of reproduction where two sex cells, usually an egg and a sperm, join to form a zygote which will develop into a new organism with a unique identity.

Sperm

haploid sex cells formed in the male reproductive organs.

egg haploid

sex cells formed in the female reproductive organs.

fertilization

in sexual reproduction the joining of a sperm and egg.

zygote

a new diploid cell formed when a sperm fertilizes an egg will divide by mitosis and develop into a new organism.

diploid

cells whose similar chromosomes occur in pairs.

Haploid

cells that have half the number of chromosomes as body cells.

meiosis

reproductive process that produces four haploid sex cells from one diploid cell and ensures offspring will have the same number of chromosomes as the parent organisms.

Hereditary

the passing of traits from parents to offspring

DNA

deoxyribonucleic acid is the genetic material of all organisms made up of two twisted strands of sugar phosphate molecules and nitrogen bases.

Rna

ribonucleic acid is a type of nucleic acid that carries codes for making proteins from the nucleus to the ribosomes.

Gene

section of DNA on a chromosome that contains instructions for making specific proteins.

Mutation

any permanent damage in a gene or chromosome of a cell may be beneficial, harmful or have little effect on the organism.