Edexcel Biology GCSE Topic 1: Key Concepts in Biology Vocabulary

Flashcards on key vocabulary terms from Edexcel Biology GCSE Topic 1: Key Concepts in Biology lecture notes.

Organelles

Structures in a cell that have different functions.

Nucleus

Contains DNA coding for a particular protein needed to build new cells; enclosed in a nuclear membrane.

Cytoplasm

Liquid substance in which chemical reactions occur; contains enzymes; organelles are found in it.

Cell membrane

Controls what enters and leaves the cell.

Mitochondria

Where aerobic respiration reactions occur, providing energy for the cell.

Ribosomes

Where protein synthesis occurs; found on a structure called the rough endoplasmic reticulum.

Differentiation

process that involves the cell gaining new sub-cellular structures in order for it to be suited to its role.

Chloroplasts

Where photosynthesis takes place, providing food for the plant; contains chlorophyll pigment which harvests the light needed for photosynthesis.

Permanent vacuole

Contains permanent vacuole; found within the cytoplasm; improves cell’s rigidity.

Cell wall

Made from cellulose; provides strength to the cell.

Cell wall (in bacterial cells)

Made of a different compound (peptidogylcan).

Plasmids

Small rings of DNA - code for extra genes to those provided by chromosomal DNA

Flagella

Long, thin ‘whip-like’ tails attached to bacteria that allow them to move

Acrosome

Top of the head of a sperm cell that has digestive enzymes which break down the outer layers of membrane of the egg cell

Haploid Nucleus

Having 23 chromosomes, rather than the 46 that most other body cells have

Cilia

Long, hair-like processes that waft bacteria trapped by sticky mucus (produced by nearby goblet cells) down to the stomach

Lignin

A chemical is deposited which causes the cells to die, become hollow and are joined end-to-end to form a continuous tube so water and mineral ions can move through

Sieve plates

Cell walls of each cell when they break down form structures allowing the movement of substances from cell to cell

Microscopes

Enlarges the image of extremely small structures such as cells which cannot be seen without them

Resolving power

The ability to distinguish between two points

Biological catalysts

A substance that increases the rate of reaction without being used up

Active site

Enzyme's uniquely shaped location where the substrate binds

Enzyme-substrate complex

The shape of the substrate is complementary to the shape of the active site, so when they bond it forms