S1 Cells and Reproduction

Cell

basic unit of life that makes up living organisms

Cell membrane

controls what enters and leaves the cell

Cell wall

supports the plant cell. Is made of cellulose

Cytoplasm

site of chemical reactions in a cell

Chloroplast

where photosynthesis occurs in plant cells

Multicellular

made up of multiple cells

Nucleus

controls the cells activities

Photosynthesis

process which plants convert light energy into sugar

Stain

used to show cell structures more clearly when using a microscope

Unicellular

made up of only one cell

Vacuole

stores cell sap in a plant cell

Bases

four bases in DNA - A, T, G and C - that join the two strands

Chromosome

found inside nucleus made up of long strands of DNA

DNA

genetic information which controls cell function

DNA Profiling

used to identify individuals based on their DNA

Double-stranded helix

the shape of a DNA molecule

Gene

a piece of DNA with instructions how to make a protein

Inherited

genes passed on from parents e.g. eye colour.

Amniotic sac

contains amniotic fluid and protects the developing foetus

Antibody

produced by white blood cells to fight infections.

Cervix

entrance to the uterus

Colostrum

type of breastmilk which is rich in antibodies

Egg cell

female gamete which is produced in the ovaries

Fertilisation

the nucleus of the male and female gamete fuse together

Gamete

sex cells containing half the genetic information

Ovaries

where female gamete (egg cells) are produced

Oviduct

where fertilisation takes place

Penis

puts sperm in the vagina during sexual intercourse

Placenta

organ which allows substances to pass between mother and foetus

Reproduction

process where organisms produce offspring

Sperm cell

male gamete produced in the testes

Sperm duct

carries sperm from testes to penis

Testes

where sperm cells are produced

Umbilical cord

connects foetus to placenta

Uterus

where foetus develops.

Vagina

where sperm are placed during sexual intercourse

Zygote

cell created from fertilisation which has a full set of chromosomes

Allele

different versions of a gene

Continuous variation

characteristics with a whole range of numbers

Discrete variation

characteristics can be placed in distinct groups

Dominant

characteristic will always show in the individual

Mutation

random change to the DNA of a cell

Recessive

characteristic that can be masked (hidden) by a dominant gene

Variation

differences between members of a species