Cell Biology Flashcards
What is a eukaryotic cell?
A cell with genetic material (DNA) enclosed in a nucleus
What is a prokaryotic cell?
A cell where genetic material (DNA) is not enclosed in the nucleus. E.g bacterial cell
Compare eukaryotic and prokaryotic cells
- Eukaryotic has a nucleus
- Prokaryotic does not have a nucleus, but a single loop of DNA or plasmids.
- Eukaryotic > prokaryotic
- Both contain cytoplasm.
What is a specialised cell?
Most cells are specialised. They have other adaptations to help them carry out a certain function.
What do you scientists call a cell that has been specialised?
Differentiation.
Job of the sperm cell?
To join in with an ovum, egg cell. This is called fertilisation.
Where do sperms cells store the genetic material?
It is stored in their nucleus but sperms cells contain only half of the genetic information of a normal adult cell.
What is the order of magnitude?
How much larger something is by it being 10x greater than before.
E.g, 1 order of magnitide=10x
2 order of magnitude=100x
Plant cell extra features and adaptations
- Chloroplasts contain chlorophyll and are the site of photosynthesis.
- Cell wall is made from cellulose, which strengthens the cell.
- Vacoule is filled with cell sap, which can help give the plant its shape.
Features of sperms cells
- Long tail to help them swim to egg cell. Aslo streamlined to make this easier.
- Packed full of mitochondria to give energy needed for swimming.
- Contain enzymes that allow them to digest their way through the outer layer of the egg cell.
- Contain genetic material in nucleus. Sperm cells sonatina half of DNA of a normal adult cell
Job of nerve cells
Send electrical impulses around the body
Nerve cell adaptaions
- Axon carries the electrical impulses around one part of the body to another. They are the part along the cell.
- Myelin insulates the axon and speeds up the transmission of nerve impulses. They cover the axon.
- Synapses are located at the end of the axon. They allow impulses to pass from one nerve cell to another.
- Dendrites increase surface area so that the other nerve cells can connect more easily. Looks like a splatter on one end.
How do muscle cells contract?
They have protein fibres that can change their length. When a muscle cell contracts, the protein fibres shorten, decreasing the length of the cell.
What are muscle cells packed with?
Mitochondria to provide energy for muscle contraction.
What is the function of hair in a root hair cell?
They increase the surface area of the root so it can absorb water and dissolve minerals more effectively.