B1 Flashcards
Name the independent variable in the osmosis and potato RP
Concentration
Name the dependent variable in the osmosis and potato RP
Change in mass
Name the control variable in the osmosis and potato RP
Temperature
Time
What is the role and adaptation of a sperm cell?
Role: transport male DNA to the female DNA
Adaptation: long tail, lots of mitochondria for energy
What is the role and adaptation of a nerve cell?
Role: send electrical impulses around the body
Adaptation: long to cover more distance, branched connections to connect in a network
What is the role and adaptation of a muscle cell?
Role: contract quickly
Adaptation: long, lots of mitochondria for energy
What is the role and adaptation of a root hair cell?
Role: absorb water from soil
Adaptation: large surface area to absorb more water
What is the role and adaptation of a phloem?
Role: transport substances around the plant
Adaptation: cells are long and joined end-to-end
What is the role and adaptation of a xylem?
Role: transport water through the plant
Adaptation: hollow center, strengthened with lignin
What’s the difference between an electronic microscope and a light microscope?
Electronic microscope:
more expensive
higher resolution
need training to use
can see sub-cellular structures
Light microscope:
cheaper
lower resolution
don’t need training to see
can’t see sub-cellular structures
How do you convert millimeters to micrometers?
Multiply by 1000
Give 2 examples of a eukaryotic cell
Animal cell
Plant cell
Give an example of a prokaryotic cell
Bacteria
Describe an animal cell
Nucleus (genetic material)
Ribosomes (proteins)
Mitochondria (aerobic respiration)
Cell membrane (controls what goes in and out)
Cytoplasm (chemical reactions)
What features does ONLY a plant cell have?
Rigid cell wall (support)
Vacuole (cell sap)
Chloroplasts (photosynthesis)
Describe a bacterial cell
Cell wall
Single strand of DNA
Cell membrane
Plasmids
Cytoplasm
Define differentiation
A cell changes to become specialised for its job
What is a sperm cell specialised for?
Reproduction
What is a nerve cell specialised for?
Rapid signaling
What is a muscle cell specialised for?
Contraction
What is a root hair cell specialised for?
Absorbing water and minerals
What are xylem and phloem specialised for?
Transporting water and substances
Where is genetic material contained?
Chromosomes
How many PAIRS of chromosomes are there in a human cell?
23
Define osmosis
The movement of water molecules from a high concentration to a low concentration
Define active transport
The movement of particles from a low concentration to a high concentration (against a concentration gradient)
Name 5 sub-cellular structures that BOTH plant and animal cells have
Nucleus
Cell wall
Cytoplasm
Ribosomes
Mitochondria
What are the 3 stages in the cell cycle?
- Replication of DNA and organelles
- Mitosis
- Cell divides
What does the DNA need to do in the cell cycle before it divides?
Duplicate
What are the two sources of human stem cells?
Adult bone marrow
Embryos
Name 2 uses of stem cells
Repair of blood cells
Making brain cells
Repairing pancreas
Why are some people against stem cells?
People feel it’s unethical because stem cells come from embryos - deterring potential life
How is the lungs adapted for gaseous exchange?
Large surface area
Moist lining
Thick supply of blood
Thin walls
Name the structure in the small intestine where nutrients are absorbed into the blood stream
Villi
What does ‘semi-permeable’ mean?
Only small molecules (water) can pass through - not salt or sugar
