B1 Cell biology Flashcards
Eukaryotic Cells
They have DNA that forms chromosomes which are contained in a nucleus. E.g. Plant and Animal Cells- made of multiple cells
Prokaryotic Cells
- single-celled
- no nucleus, one loop of DNA
- have small rings of DNA called plasmids
- smaller than eukaryotic cells
mitochondria
THE POWERREALISER OF THE CELL
where energy is released through respiration in the form of ATP
cell membrane
controls the movement of substances in and out of the cell: a semi permeable membrane
ribosomes
site of protein synthesis
cytoplasm
jelly-like substance where chemical reactions happen
permanent vacuole
contains cell sap
not in animal cell
chloroplasts
contains chlorophyll (a green pigment) to absorb light energy for photosynthesis not in animal cell
cell wall
made of cellulose which strengthens and supports the cell
not in animal cell
flagellum
used by bacteria and sperm for movement
Tail like structure
sperm cell
fertilises an ovum (egg)
flagellum to swim to the ovum
lots of mitochondria for energy and respiration enables the sperm to swim
electron microscope
uses a beam of electrons to form photos samples can't be living expensive high magnification high resolution
light microscope
uses light to form images living samples can be used relatively cheap low magnification low resolution
red blood cell
transports oxygen around the body
no nucleus for room to carry more oxygen
contains haemoglobin (red pigment)that binds to oxygen molecules
flat bi-concave disc shape to increase surface area to volume ratio
muscle cells
contract and relax to allow movement
contains protein fibres which contract to make the cells shorter
contains lots of mitochondria to release energy for respiration for contraction
nerve cells
carry electrical impulses around the body
branched endings called dendrites allow connections to other neurones and effectors
the myelin sheath insulates the axon to increase the transmission speed of electrical impulses
root hair cells
absorb mineral ions and water from the soil
long projection speeds up the absorption of water and mineral ions by increasing the surface area of the cell
lots of mitochondria for the energy released to be used for the active transport of mineral ions
palisade cells
enables photosynthesis in the leaf
lots of chloroplasts containing chlorophyll to absorb light energy located on the top surface of the leaf where it can absorb the most light energy from the sun.