National 5 Biology - Cell Structure and Transport Across Cell Membranes

Vocabulary flashcards reviewing cell structure and transport across cell membranes based on National 5 Biology notes.

Ultrastructure

The fine structure and detail of a cell and its organelles which can only be seen using an electron microscope

Cell wall

The structure which provides structure and support. It prevents the cell from bursting

Mitochondrion

The organelle which is the site of aerobic respiration

Chloroplast

An organelle containing chlorophyll; the site of photosynthesis

Cell membrane

A selectively permeable membrane enclosing the cell cytoplasm and controlling the entry and exit of materials

Cytoplasm

A jelly-like liquid containing cell organelles and the site of many chemical reactions

Vacuole

A membrane-bound sac containing cell sap in plant cells

Ribosome

The site of protein synthesis

Nucleus

The organelle that contains the genetic information of the organism and controls cell activities

Plasmid

Circular ring of DNA present in bacterial cells and used in genetic engineering

Cellulose

The structural carbohydrate of which plant cell walls are composed

Plant, fungal and bacterial cells

The types of cells that have cell walls

Bacterial cells

Type of cells containing a plasmid

Organelles

Structures found inside the cells

Phospholipids

Two layers of phospholipid molecules which can have molecules embedded

Proteins

Structures that make up part of the cell membrane embedded in the phospholipid bilayer

Selectively permeable

Refers to a membrane feature that means to control the movement of certain molecules depending on their size

Passive transport

The movement of molecules without the need for additional energy e.g. diffusion and osmosis

Diffusion

The passive movement of molecules from an area of higher concentration to an area of lower concentration

Osmosis

The movement of water molecules from an area of higher water concentration to an area of lower water concentration through a selectively permeable membrane

Burst

When an animal cell gains water by osmosis

Shrink

When an animal cell loses water by osmosis

Turgid

A swollen plant cell with a full vacuole resulting from water intake due to osmosis

Plasmolysed

A plant cell in which the vacuole has decreased in size and the membrane has pulled away from the wall due to water loss

Active transport

The transport of molecules against their concentration gradient that requires energy

Concentration gradient

A difference in concentration between two solutions, cells or solutions and cells