chapter 1 - cell structure and transport Flashcards
what kind of cell is eukaryotic?
animal and plant cells
what kind of cell is prokaryotic?
bacteria cells
what is found in the nucleus of animal and plant cells?
DNA
function of cell membrane?
to control movement of substances in and out of the cell
function of mitochondria?
the site of respiration to transfer energy to the cell
function of chloroplasts?
contain chlorophyll to absorb light energy for photosynthesis
function of cell wall?
strengthens and supports the cell
structure of main genetic material in prokaryotic cell?
a single loop of DNA
electron microscopes VS light microscopes?
electron microscopes:
- use beams of electrons instead of light
- cannot be used to view living samples
- are much more expensive
- have a much higher magnification and resolution
function of red blood cell?
to carry oxygen around the body
adaptations of red blood cell?
- no nucleus to make extra space for haemoglobin
- contains a red pigment called haemoglobin
- they have a bi-concave disc shape
function of nerve cell?
to carry electrical impulses around the body
function of sperm cell?
to fertilise an ovum (egg)
adaptations of sperm cell?
- a tail to help them swim
- lots of mitochondria to release energy for swimming
function of palisade cell?
to carry out photosynthesis in a leaf
adaptations of palisade cell?
- have lots of chloroplasts for photosynthesis
- are located at the top surface of the leaf to absorb maximum light energy
function of root hair cell?
to absorb minerals and water from the soil
adaptations of root hair cell?
- large surface area to increase the rate of diffusion and osmosis
- lots of mitochondria to release energy for active transport
what is diffusion?
the net movement of particles from an area of high concentration to an area of low concentration down a concentration gradient
> a passive process, doesn’t require energy from respiration
factors that affect the rate of diffusion?
- concentration gradient
- temperature
- membrane surface area
how are villi adapted for exchanging substances?
- a long, thin shape - increases surface area
- a one-cell-thick membrane - short diffusion pathway
- a good blood supply - maintains a steep concentration gradient
how are lungs adapted for efficient gas exchange?
- alveoli - large surface area
- moist membranes - increases rate of diffusion
- one-cell-thick membranes - short diffusion pathway
- good blood supply - maintains a steep concentration gradient
how are fish gills adapted for efficient gas exchange?
- large surface area for gases to diffuse across
- thin layer of cells - short diffusion pathway
- good blood supply - maintains a steep concentration gradient
what is osmosis?
the diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane