B1 - Cell Biology Flashcards
(38 cards)
Define Prokaryotic organisms.
Small, simple celled organisms.
Define Eukaryotic organisms.
Complex celled organisms.
Give an example of Eukaryotic cells.
Animal or Plant cells.
Give an example of Prokaryotic cells.
Bacteria.
Name the 5 parts of an animal cell.
- Nucleus
- Cytoplasm
- Cell membrane
- Mitochondria
- Ribosomes
The plant cell has all the parts of the animal cell plus three extra. Name those extra three parts.
- Cell wall
- Permanent vacuole
- Chloroplasts
What five parts don’t Bacteria cells have that plant cells do.
- Ribosomes
- Mitochondria
- Chloroplasts
- Vacuole
- Nucleus
Bacterial cells don’t have a “true” nucleus - instead they have a …
single circular strand of DNA that floats freely in the cytoplasm.
What might bacterial cells also contain?
Plasmids.
What is the purpose of a microscope?
To help us see what we cannot see with the naked-eye.
Light microscopes use…
Light and lenses to form an image of a specimen and magnify it.
Electron microscopes use…
Electrons instead of light to form an image with higher magnification than light microscopes.
What is “higher resolution”?
The ability to distinguish between two points and give a sharper image.
What is the importance of electron microscopes?
To see smaller things in more detail like the internal structure of mitochondria.
What is the formula for Magnification?
Magnification = Image size / real size
What is differentiation?
The process by which a cell changes to become specialised for its job.
What happens as a cell changes?
They develop different subcellular structures and turn into different types of cells, allowing them to carry out specific functions.
What are the cells that differentiate in mature animals mainly used for?
Repairing and replacing cells such as skin or blood cells.
What are the five required examples of specialised cells and their specialisations?
- Sperm cells (reproduction)
- Nerve cells (rapid signalling)
- Muscle cells (contraction)
- Root hair cells (absorbing water and minerals)
- Phloem and Xylem cells (transporting substances)
How does the nucleus contain the genetic material of someone?
In the form of chromosomes.
What are chromosomes?
Coiled up lengths of DNA molecules.
What does each chromosome carry?
A large number of genes.
What do genes in chromosomes do?
Different genes control the development of different characteristics.
How many chromosomes are in the human cell?
46 (23 pairs).
