Topic 1 Cell Biology Flashcards
Key Terms/Key Knowledge
Define Active transport
The movement of substances from a more dilute solution to a more concentrated solution (against a concentration gradient) with the use of energy from respiration.
Define Cell differentiation
The process where a cell becomes specialised to its function.
Define Cell membrane
A partially permeable barrier that surrounds the cell.
Define Cell wall
An outer layer made of cellulose that strengthens plant cells.
Define Chloroplast
An organelle which is the site of photosynthesis.
Define Chromosomes
DNA structures that are found in the nucleus which are made up of genes.
Define Concentration gradient
The difference in concentration between two areas.
Define Diffusion
The spreading out of the particles of any substance in solution, or particles of a gas, resulting in a net movement from an area of higher concentration to an area of lower
concentration.
Define Embryonic stem cell
A type of stem cell that can differentiate into most types of human cells.
Define Eukaryotic cell
A type of cell found in plants and animals that contains a nucleus.
Define Magnification
How much bigger an image appears compared to the original object.
Define Meristematic cells
A type of stem cell that can differentiate into any type of plant cell.
Define Mitochondria
An organelle which is the site of respiration.
Define Mitosis
A type of cell division which produces two genetically identical daughter cells from one parent cell.
Define Nucleus
An organelle found in most eukaryotic cells that contains the genetic material of the cell and controls the activities of the cell.
Define Organelle
A specialised structure found inside a cell.
Define Osmosis
The diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane.
Define Plasmid
Loops of DNA found in the cytoplasm of prokaryotic cells.
Define Prokaryotic cell
A type of cell found in bacteria that does not contain a nucleus.
Define Resolution
The ability to distinguish two different points in a specimen.
Define Specialised cells
Cells that are adapted to perform a specific function.