Cell Structure: Membrane, Cytoplasm, Nucleus, Chromosomes, DNA, Genes, and Cell Wall

Vocabulary flashcards covering key cell components and their basic features as described in the notes.

Cell membrane

Also called cell surface membrane; made of lipids and proteins; separates the cell from the environment; regulates which substances can enter or leave the cell.

Cytoplasm

Jelly-like substance between the cell membrane and the nucleus; contains mostly water and dissolved substances; site of most cell activities.

Nucleus

Central organelle containing genetic material; consists of a nuclear membrane and chromosomes; controls cell activities.

Nuclear membrane

Outer covering of the nucleus that separates it from the cytoplasm; has pores that allow substances to enter or leave the nucleus.

Chromosome

Thread-like structures in the nucleus; in humans, 46 chromosomes per cell (23 from each parent); made of proteins and DNA.

DNA (deoxyribonucleic acid)

Molecule carrying genetic information along its length; genes are segments arranged on DNA.

Gene

A unit that controls a particular characteristic in the body.

Cell wall

Plant cell structure surrounding the cell membrane; made mainly of cellulose; protects the cell and gives fixed shape; fully permeable; absent in animal cells.

Cellulose

Main component of the plant cell wall.

Permeable

Capable of allowing substances to pass through; the cell wall is fully permeable.

Pores

Openings in the nuclear membrane that allow substances to enter or leave the nucleus.