Cell Biology Flashcards
What is a eukaryotic cell - give 2 examples
A cell in which the genetic material is enclosed in a nucleus - plant and animal cells (eukaryotic cells are the bigger type) 10-100 um
What is a prokaryotic cell - give an example
A cell in which the genetic material is not enclosed in a nucleus, but instead found as a singular circular loop in the cytoplasm (in a region called the nucleoid). (prokaryotic cells are the smaller type) 1 um
List the organelles (subcellular structures) of animal cells (5)
- Nucleus
- Cytoplasm
- Cell membrane
- Mitochondria
- Ribosomes
List the organelles (subcellular structures) of plant cells (8)
- Nucleus
- Cytoplasm
- Cell membrane
- Mitochondria
- Ribosomes
- Cell Wall
- Permanent vacuole
- Chloroplasts
List the organelles (subcellular structures) of bacteria cells, and their roles (6)
- Cytoplasm
- Cell Wall
- Cell membrane
- A singular circular strand of DNA that floats freely in the cytoplasm - may also have 1+ small DNA rings called plasmids
- Flagellum
- ribosomes
What is a cell?
A cell is the smallest structural and functional unit of an organism, they are typically microscopic.
List the organelles (subcellular structures) of yeast cells (4)
- Nucleus
- Cell Wall
- Cell membrane
- Cytoplasm
1m = how many cm
100 cm
1cm = how many mm?
10mm
1mm = how many micrometres? (um)
1000 um
Magnification = ?
magnification = size of image / actual specimen size
Definition of a specialised cell
A cell that is adapted to perform a specific function
All cells in the body are g__________ i________ (which means..), except for…
All cells in the body are genetically identical (contains the same DNA) except for red blood cells and gametes
Why can cells be totally different to each other
They have different sections of their DNA “switched on/off”
Specialisations and function(s) of a sperm cell (4)
Function: To get the male DNA to the female DNA, fertilise the egg cell - they are specialised for reproduction
- Has a flagellum (tail) and streamlined head for fast movement (swimming) towards the egg cell
- Acrosome contains enzymes to digest outer layer of the egg
- Nucleus contains only half the number of chromosomes needed (23) the rest come from fusion with egg cell during fertilisation - it is a haploid cell
- Has lots of mitochondria on it’s middle section, so that lots or aerobic respiration can take place, to release lots of energy, so that the sperm cell has enough energy to move quickly.
Specialisations and function(s) of an egg cell (3)
Function: To fuse with the sperm cell and become a fertilised egg
- Nucleus contains only half the number of chromosomes needed (23) the rest will come during fusion with the sperm cell during fertilisation - it is a haploid cell
- Very large for easy location by sperm cell
- Has lot’s of resources in it’s cytoplasm for survival in the fallopian tube of the fertilised egg
Specialisations and function(s) of a nerve cell (5)
Function: To carry electrical signals from one part of the body to another
- They are very long
- Axons conduct electricity through the body, and is insulated with a fatty layer (myelin sheath)
- Lot’s of dendrites to make connections with other nerve cells
- Synapses are adapted to pass the impulses to other cells or between a nerve cell and a muscle using special transmitter chemicals
- They contain lots of mitochondria to provide the energy needed to make the transmitter chemicals
Specialisations and function(s) of a muscle cell - striated (smooth is the one that forms one of the layers of tissue in the digestive system) (3)
Function: To contract quickly
- Have lots of mitochondria (so that they can do lots of aerobic respiration and release lots of energy) becuase they need lots of energy in order to contract and move your limb quickly and efficiently
- They contain special proteins that slide over each other making the fibres contract
- They can store glycogen - a chemical that can be broken down and used in cellular respiration and by mitochondria to transfer energy needed for fibres to contract