Exam Revision Sem 1 Flashcards
(101 cards)
Function of mitochondria
Double membrane
Cellular respiration
Makes energy available for the cells activities
Function of Golgi apparatus?
Modifies proteins and packages them for secretion from the cell
Centrioles:
Involved in the reproduction of the cell
Endoplasmic reticulum:
Provides a surface for chemical reactions
Lysosomes:
Contain digestive enzymes
When particles/liquids enter the cell they form vesicles in cytoplasm, lysosomes join these vesicles and break down material
Nucleus:
Membrane separates from cytoplasm, stores energy and genetic information (DNA)
Why are cells so small?
All the requirements of a cell and the organelles must pass across the membrane
Inclusions?
Chemical substances occurring as granules or liquid droplets in the cytoplasm
Structure of the cell membrane?
Semipermeable
Separates cell from neighbouring cell
Separates intercellular fluid and extracellular fluid
Gives the cell structure
Passive process?
Requires no energy, moves with the concentration gradient examples include diffusion, osmosis
Active processes?
Require energy, move against the concentration gradient
Examples are active transport, vesicular transport
What is osmosis?
Diffusion of water, requires channel proteins
Movement of water from a region of high water concentration to a region of low water concentration
What is carrier-mediated transport?
When large molecules are too big to pass through channels, they attach to a binding site on the carrier (proteins are specific)
What is vesicular transport?
Movement of substances in vesicles across the membrane.
What is exocytosis?
Removing a liquid/solid out of the cell
Vesicle formed inside the cell via the Golgi apparatus
Vesicle then fuses with cell membrane and contents are pushed outside into extracellular fluid.
What is endocytosis?
Taking liquids/solids into a cell
Cell membrane folds around the particle and encloses, forming a vesicle
Vesicle then suspended in the cytoplasm
Pinnocytosis?
Movement of liquid into cell
Phagocytosis?
Movement of solids into a cell
What is homeostasis?
Where the body systems work together to make sure the cellular environment stays constant. (Temperature and fluid concentration)
What is facilitated diffusion?
A passive process where particles move from an area of high concentration to low concentration, require no energy and move against the concentration gradient
Three types of osmotic solutions?
Isotonic
Hypotonic
Hypertonic
Isotonic:
There is the same concentration of solute molecules inside and outside the cell
Hypotonic:
Solute outside the cell is low concentration (10%) inside the cell higher solute conc (90%)
When water moves into the cell osmotic pressure increases
Hypertonic:
Greater concentration of solute molecules outside the cell rather than inside
Water moves outside the cell causing it to shrink.