topic 1 -cell biology Flashcards
What subcellular structures are common in both eukaryotic cells [plants and animals ]
cell membrane
cytoplasm
genetic material enclosed in a nucleus
mitochondria
ribosomes
what are cells?
the basic unit of all forms of life
prokaryotic cells
prokaryotic cells - bacteria cells
smaller than eukaryotic cells
simple
single-celled organisms
no nucleus
plasmids
no chloroplast or mitochondria
plant cells
have all the same subcellular structure as animal cells
plus
cell wall
permanent vacuole
chloroplast
what subcellular structure is the same in plants and algae
cell wall made of cellulose, which
strengthens the cell.
how are sperm cells specialized?
main function - get male DNA to the female DNA [reproduction]
they have a long tail and a streamlined head to help them swim better
they have enzymes in their head that allow it to be digested through the egg cell membrane
they have a lot of mitochondria which provide energy for them
how are nerve cells specialized?
specialized for rapid signaling
main function - to carry electrical signals from one part of the body to another
the cells are long so they cover more distance
branched connections at their ends to connect to other nerves and form connections throughout the body
how are muscle cells specialized?
specialized for contraction
main function - to contract quickly
the cells are long so they have more space to contract
lots of mitochondria to generate the energy needed to contract
how are root hair cells specialized?
specialized for absorbing water and nutrients
they are cells on the surface of a plants roots which grow long ‘hairs’ that stick out into the soil
this gives the plants large surface area for absorbing water and mineral ions from the soil
how are phloem cells specialized?
from phloem tubes
transports food around the plant
the cells are long and join end-to-end
very few subcellular structures so stuff can flow through it
how are xylem cells specialized?
from xylem tubes
transports water around the plant
they are hollow in the center so stuff can flow through them
when do Most types of animal cells differentiate at
early stage
what is differentiation
the process by which a cell changes to become specialized for its job
when do plants lose their ability to differentiate
never
what are cells in mature animals used for
repair and replace damaged cells
e.g skin or blood cells
