BIO P1 Flashcards
What is a eukaryotic cell?
A cell that contains a nucleus
Name 2 features of a prokaryotic cell
Doesn’t contain a nucleus
Smaller than a eukaryotic cell
describe 3 differences between prokaryotic cells and eukaryotic cells
Eukaryotic cells contain a nucleus and mitochondria
Prokaryotic cells contain plasmids (loop DNA)
Describe the function of ribosomes
Proteinsynthesis
Describe the location and function of mitochondria
Found in the cytoplasm, site of aerobic respiration
Describe 3 differences between plant and animal cells
Plant cells have a permanent vacuole, a cell wall and chloroplasts
What structures keep plant cells rigid?
Permanent vacuole
Cell wall
Describe the function of chloroplasts
Site of photosynthesis
Contains chlorophyll (green pigment) which absorbs light
Describe the function of the cell membrane
Controls what substances enter and leave the cell
Describe an advantage of an electron microscope over a light microscope
It has a higher magnification
It has a higher resolution
What is a concentration gradient?
A measurement of how a concentration of a substance changes from one place to another
What is a passive process?
No additional energy is needed
It occurs naturally
Define the term diffusion
Movement of particles from a higher concentration to a low concentration
Name the adaptations alveoli has to help diffusion
Large surface area
Moist membranes
Lining is one cell thick
Rich blood supply
Explain why diffusion in insects is so small
Maximum size of insects is determined by how quickly oxygen can quickly diffuse into their cells
Define the term osmosis
Water moving from a higher concentration to a lower concentration across a partially permeable membrane
Define the term partially permeable membrane
Only allows substances of a certain size through
What is meant by isotonic
Two solutions have the same concentrations across a partially permeable membrane so there is no overall movement of water
What is active transport?
The movement of particles from a low concentration to a high concentration using energy
Where does active transport happen in humans
Absorption of sugar by the small intestine after a low carbohydrate meal
Where does active transport occur in plants
Uptake of minerals by root hair cells
Describe the role of the small intestine
Absorbs small food molecules
Describe bile and its 2 functions
Green liquid produced by liver released into small intestine
Emulsifies fats
Neutralises hydrochloric acids from stomach
Describe two functions of stomach acid
Provides optimum pH for protease enzymes to work
Kills pathogens
Describe the function of the large intestines
Absorbs water
Describe peristalsis
Rhythmic contracting and relaxing of muscles lining the digestive system
Where is protease produced?
Stomach and pancreas
Where is carbohydrase produced?
Salivary glands and pancreas
Where is lipase produced?
Pancreas
Describe the location of the villi and its function
Lines the small intestine
Massively increase surface area of small intestine to increase absorption of food molecules
Describe the role of the vena cava
The blood vessel that carries blood from the body to the heart
Describe the role of the pulmonary artery
Carries blood from the heart to the lungs
Describe the role of the aorta
Blood vessel that carries blood from the heart to the body