Chapter 1- Life Processes Flashcards
What are the eight life processes?
Require nutrition Excrete Move Grow and develop Respire Respond to stimuli Reproduce Control
What is the definition of a cell?
The smallest unit of life
The living material that makes up a cell is called…?
Cytoplasm
An animal cell contains what organelles?
Nucleus
Cell membrane
Mitochondria
Cytoplasm
A plant cell contains what organelles?
Cell wall Cell membrane Vacuole Cytoplasm Mitochondria Chloroplasts Nucleus
What is meant by selectively permeable?
Controls which substances pass in either direction
What is the role of the mitochondria?
They carry out some of the reactions of respiration
The cell wall is made out of what non-living material?
Cellulose
What is meant by freely permeable?
There is no barrier to water or dissolved substances
What are enzymes?
A group of proteins that control the chemical reactions that go on in a cell
What is a substrate?
A molecule that an enzyme acts on
What is an active site?
A small area on the enzymes surface where the substrate attaches to
List the factors that effect enzymes
Temperature - 37 degrees is the optimum temperature. Increasing temperature speeds up the rate of reaction.
Raising the concentration of the enzyme or the substrate
pH
What is cell respiration?
The break down of food molecules to release the stored chemical energy that it contains.
The chemical energy from respiration can be used for?
- Contraction of muscle cells, producing movement
- active transport of molecules and ions
- building large molecules, such as proteins
- cell division
