cell biology Flashcards
what are cells?
they’re the smallest unit of life that can replicate independently
why do animal/plant cells divide?
they do it to grow and replace dead cells instead of making whole new organisms.
structure of an animal cell:
cell membrane, nucleus, cytoplasm, mitochondria and ribosomes.
structure of a plant cell:
cell wall, cell membrane, nucleus, cytoplasm, mitochondria, ribosomes, chloroplasts (contain chlorophyll) and a permanent vacuole.
what does a cell membrane do?
controls which substances pass in and out of the cell
what does a nucleus do?
contains the genetic material/ DNA.
what does cytoplasm do?
jelly like substance where the chemical reactions take place
what does mitochondria do?
provide cells with the energy they need to function
what is a ribosome?
where proteins are made
what does a cell wall do?
supports and provides structure to the cell
what does chloroplast do?
it is where photosynthesis takes place and it contains chlorophyll which gives it its green pigment.
what does a vacuole do?
contains cell sap (mixture of sugars, salts and water)
structure of a bacterial cell (and what does each thing do):
cell wall (supports and provides structure to the cell), cell membrane (controls which substances pass in and out of the cell), ribosomes (where proteins are made), cytoplasm (jelly like substance where the chemical reactions take place), circular strand of dna (contains genes that they need to survive), plasmids (they are extra genes that give it antibiotic resistance) and flagella (propels the bacteria).
units of length:
km=10^3 (/1000) meter=0 (/1000) mm=10^-3 (/1000) μm=10^-6 (/1000) nm=10^-9
what is resolution?
the shortest distance between two points on a specimen, that can still be distinguished as two separate entities.
