Cell Biology and transport quick questions Flashcards
What are two types of eukaryotic cells
animal & plant
What type of cell are bacteria
prokaryotic
Where is DNA found in animal and plant cells
nucleus
What is the function of the cell membrane
controls movement of substances in and out of the cell
What is the function of the mitochondria
Site of respiration to transfer energy for the cell
What is the function of chloroplasts
Contains chlorophyll to absorb light energy for photosynthesis
What is the function of ribosomes
Enables production of proteins (protein synthesis)
What is the function of the cell wall
strengthens and supports the cell
What is the structure of the main genetic material in a prokaryotic cell
single loop of DNA
How are electron microscopes different to light microscopes
-use beams of electrons instead of light
-can only view dead things
-higher resolution
-higher magnification
-more expensive
What is the function of a red blood cell
transporting oxygen around the body
Give 3 adaptations of a red blood cell
-biconcave shape
-no nucleus
-contains haemoglobin
What is the function of a nerve cell
carries electrical impulses around the body
Give two adaptations of a nerve cell
-branched endings
-myelin sheath insulates the axon
What is the function of a sperm cell
fertilises an ovum (egg)
GIve 2 adaptations of a sperm cell
-flagellum (tail)
-contains lots of mitochondria
What is the function of a palisade cell
carries out photosynthesis in a leaf
Give 2 adaptations of a palisade cell
-lots of chloroplasts
-located at the top surface of the leaf
What is the function of a roothair cell
absorb minerals and water from the soil
Give 2 adaptations of a root hair cell
long projection, lots of mitochondria
What is diffusion
-net movement of particles from an area of high concentration to an area of low concentration along a concentration gradient
-this is a passive process and does NOT require energy from respiration
Name 3 factors that affect the rate of diffusion
-temperature
-concentration gradient
-membrane surface area
How are villi adapted for exchanging substances
-long and thin- increase surface area
–one cell thick- short diffusion pathway
-good blood supply- maintains a steep concentration gradient
how are the lungs adapted for efficient gas exchange
> alveoli- large surface area
moist membranes- increase rate of diffusion
one cell thick membrane- 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 bloody supply- maintains steep concentration gradient
What is osmosis
diffusion of water from a dilute solution to a concentrated solution through a semi-permeable membrane
Give one examples of osmosis in a plant
water moves from the soil into the root hair cell
WHat is active transport
movement of particles against a concentration gradient- to form a dilute solution to a more concentrated solution- using energy from respiration
WHy is active transport needed in plant roots
concentration of mineral ions in the soil is lower than inside the root hair cells
-the mineral ions must move against the concentration gradient to enter the root hair cells
WHatis the purpose of active transport in the small intestine
sugars can be absorbed when the concentration of sugar in the small intestine is lower than the concentration of sugar in the blood
An organism such as a bacterium with no nucleus
prokaryote
organelles which carry out respiration and produce energy in the form of ATP
mitochondria
a
