Science Test - Cells

cell

The smallest unit of life; cells are the building blocks of living things and can be many different shapes and sizes.

cell membrane

The structure that encloses the contents of a cell and allows the movement of some materials in and out.

cell theory

The theory that states that all living things are made up of cells and that all cells come from pre-existing cells.

cellular respiration

A series of chemical reactions in which the chemical energy in molecules such as glucose is transferred into ATP molecules, which is a form of energy that the cells can use.

chlorophyll

The green-coloured chemical in plants, located in chloroplasts, that absorbs light energy so that it can be used in the process of photosynthesis.

chloroplasts

Oval-shaped organelles that are involved in the process of photosynthesis, which results in the conversion of light energy into chemical energy.

cytoplasm

The jelly-like material inside a cell; it contains many organelles, such as the nucleus and vacuoles.

cytosol

The fluid found inside cells.

electron microscope

An instrument used for viewing very small objects; an electron microscope is much more powerful than a light microscope and can magnify things up to a million times.

eukaryote

Any cell or organism with a membrane-bound nucleus (e.g. plants, animals, fungi and protists).

light microscope

An instrument used for viewing very small objects; a light microscope can magnify things up to 1500 times.

magnification

The number of times the image of an object has been enlarged using a lens or lens system.

metabolism

The chemical reactions occurring within an organism that enable the organism to use energy and grow and repair cells.

micrometre

One millionth of a metre.

mitochondria

Small, rod-shaped organelles that are involved in the process of cellular respiration.

multicellular

Made up of many cells.

nanometre

One billionth of a metre.

nucleus

A roundish structure inside a cell that acts as its control centre.

organelle

Any specialised structure in a cell that performs a specific function.

photosynthesis

A series of chemical reactions that occur within chloroplasts in which light energy is converted into chemical energy.

prokaryote

Any cell or organism without a membrane-bound nucleus (e.g. bacteria).

ribosomes

Small structures within a cell in which proteins such as enzymes are made.

tissue

A group of cells of similar structure that perform a specific function.

unicellular

Made up of only one cell.

vacuoles

Sacs within a cell used to store food and wastes; plant cells usually have one large vacuole.