B1 - Cell Biology Flashcards
Prokaryotic cells
simple cells without a nucleus
Eukaryotic cells
complex cells containing a nucleus
subcellular structures
nucleus cytoplasm cell membrane mitochondria ribosomes cell wall permanent vacuole chloroplasts plasmids
Nucleus
Controls cell and contains DNA
Cytoplasm
Gel like substance. Contains enzymes. Is where most chemical reactions take place.
Cell membrane
Controls what goes in and out. Holds cell together.
Mitochondria
Where most reactions of aerobic respiration takes place
Ribosomes
where proteins are made
Cell wall
made of cellulose. supports and strengthens cell
Permanent vacuole
Contains cells sap
Chloroplasts
Where photosynthesis takes place. Contains chlorophyll.
Plasmid
Contains DNA
Subcellular structures of an animal cell
Nucleus Cytoplasm Cell membrane Mitochondria Ribosomes
Subcellular structures of an animal cell
Nucleus Cytoplasm Cell membrane Mitochondria Ribosomes Cell wall Permanent Vacuole Chloroplasts
Subcellular structures of a bacteria cell
Cytoplasm
Cell membrane
Cell wall
Plasmids
Differentiation
Process where a cell changes to become specialised for its job
Sperm cells are specialised for…
Reproduction. Long tail to help it swim and mitochondria to provide it energy to do so. Also carries enzymes so it digests through the egg cell membrane.
Nerve cells are specialised for…
Rapid signalling. Long and have branched connections to connect to other nerve cells an form a network.
Muscle cells are specialised for…
Contraction. Long so they have space to contract. Contain lots of mitochindria to generate energy for contraction.
Root hair cells are specialised for…
absorbing water and minerals. Big surface area to absorb water and minerals.
Phloem and Xylem cells are specialised for …
Transportation. Xylems are hollow and Phloem have few subcellular structures so that they can allow stuff to flow through them.
Chromosomes
Carries genes and is in the nucleus. Body cells have two copies of each chromosomes (from mother and from father). A human cell has 46 chromosomes (23 pairs).
Cell cycle
Body cells divide to produce new cells to grow or replace damaged cells. The two mains stages of the cell cycle are: 1) Growth and DNA replication 2) Mitosis
Growth and DNA replication
1) DNA is spread out into long strings
2) Cell grows and increases its subcellulars strucures e.g. mitochondria
3) Cell duplicates it’s DNA. DNA is copied and forms X-shaped chromosomes.
