definition of cell biology
the exploration and study of life, at
the level of the cell and how
those parts function at a
molecular level.
definition of a cell
structural and functional unit
of all living organisms
often called the building
block of life.
what order is the cell organisation
- Cell
- Tissue – group of cells functioning
together. - Organ – group of tissues
functioning together. - Organ System – group of organs
functioning together. - Organism – group of organ
systems functioning together.
what is the make up of a cell
90% water, rest 50% is protein, 15% carbohydrate,
15% nucleic acid, 10% lipid and 10% other.
what are the 2 main families of cells
prokaryotic and eukaryotic
what ways can we analyse a cell
- Cell culture
- Light microscopy
- Fluorescent microscopy
- Electron microscopy
- Many other like confocal microscopy, NMR etc.
what calls can be used as experimental models
- Bacteria: E.coli
- Yeast
- Dictyostelium: cell movement
- Nematode worm: C.elegans in development
- Drosphophila, mouse, bovine, human, zebrafish.
plasma membrane function
serves as a boundary between the cell and its external environment
it allows materials to pass i and out of the cell
nucleus function
- Regulates cell function.
- Surrounded by a double-layered membrane (nuclear envelope)
with large pores that allow materials to pass in and out of the
nucleus. - Contains chromatin – long tangles of DNA.
nucleolus function
- Found in the nucleus and responsible for ribosome production. Ribosomes are the sites of protein production
cyptoplasm function
- The jelly-like material that surrounds the organelles.
Endoplasmic reticulum function
- Folded membrane that acts as the cell’s delivery
system. - Smooth E.R. contains enzymes for lipid synthesis.
- Rough E.R. is studded with ribosomes for protein
synthesis.
Golgi apparatus function
- A series of flattened sacs where newly made lipids and proteins from the E.R. are repackaged and shipped to the plasma membrane.
Peroxisomes functions
Membrane bound packets of oxidative enzymes.
Vacuoles function
A sac of fluid surrounded by a membrane used to store food, fluid, or waste product
Lysosomes functions
- Contain a digestive enzymes.
- Can fuse with vacuoles to digest food, or can digest worn cell parts.
Mitochondria functions
- Produce the energy for the cell.
- Also known as the “powerhouse of the cell”.
- Has a highly folded inner membrane (cristae)
Cytoskeleton function
- A network of thin, fibrous materials that act as a
scaffold and support the organelles. - Microtubules – hollow filaments of protein.
- Microfilaments – solid filaments of protein.
what is involved in locomotion in specialised cells
cilia - Short, numerous, hair-like projections from the plasma membrane that move with a coordinated beating action
flagella - Longer, less numerous projections from the plasma membrane that move with a whip-like action
centrioles function
made of protein- tubulin.
play a role in the splitting of the cell into two cells. Replicate
then separate.
found in animal and fungi cells
what is the role of the mitochondria
Energy conversion using oxygen, fatty acid metabolism, the urea cycle,
biosynthesis of haemoglobin, necrosis or apoptosis
describe the shape of the mitochondria
0.5μm in diameter
* Have own circular DNA
