Cell bioligy Flashcards
subcellular structures
the different parts of a cell
what are the subcellular structures of an animal cell
Nucleus, cytoplasm, cell membrane, mitochondria, ribosomes
what are the subcellular structures of a plant cell
usually has all the bits an animal cell and has the extra:
cell wall, permanent vacuole, chloroplasts
Nucleus
contains genetic material that controls the activities of a cell
cytoplasm
gel like substance where most of the chemical reactions happen.
it contains enzymes that control these chemical reactions
Cell membrane
holds the cell together and controls what goes in and out.
mitochondria
these are where most of the reactions for aerobic respirations happen.
respiration transfers energy that the cell needs to work
ribosomes
this is where protein synthesise occurs (where protein is made)
cell wall
made of cellulose
supports the cell and strengthens it
referred to as rigid in plant cell
permanent vacuole
contains cell sap, a weak solution of sugar and salts
chloroplasts
where photosynthesis occurs, which makes the food for the plant. They contain a green substance called chlorophyll, which absorbs the light needed for photosynthesis.
Bacterial cells subcellular structure
cell membrane, cytoplasm, cell wall, contains one or more small rings of DNA called plasmids.
differentiation
process by which a cell changes to become specialised for its job
sperm cells are specialised for ?
reproduction
nerve cells are specialised for ?
Rapid signalling
muscle cells are specialised for
Contraction
Root hair cells are specialised for ?
Absorbing water and minerals
Phloem and xylem cells are specialised for ?
Transporting substances
Chromosomes
Coiled up lengths of DNA molecules
Growth and DNA replication
- in a cell thats not dividing, DNA is all spread out in long strings
- before it divides, cell has to grow and increase amount of subcellular structures such as mitochondria and ribosomes
- It then duplicates its DNA so there’s one copy for each new cell. DNA is copied and forms X-Shaped chromosome. Each arm of chromosome is an exact duplicate of the other
Mitosis
Once its contents and DNA have been copied the cell is ready for mitosis.
4. Chromosomes line up at the centre of the cell and cell fibres pull them apart. The two arms of each chromosome go to opposite ends of the cell
5. Membranes form around each of the sets of chromosomes. These become the nuclei of the two new cells, the nucleus has divided.
6. Cytoplasm and cell membrane divide.
The cell has now produced 2 new daughter cells. The daughter cells contain exactly the same DNA
