Microscopes and Specialised Cells Flashcards
What is magnification
how many times larger the image of an object is compared to the actual size
What is resolution
the ability to distinguish between two points (how detailed or blurry an image is)
What is the difference between electron and light microscopes
electron microscopes have a greater magnification and resolution than light microscopes and allows scientists to study sub-cellular structures in more detail
Total magnification =
eyepiece lens magnification x objective lens
magnification formula
image size / actual size
how many micrometers in a milimeter
1000
what does specialised cell mean
cells with particular shapes and organelles to carry out a specific function
what is differentiation
the process by which the cells change to become specialised
nerve cell function and adaptation
Function - carry electrical impulses.
Adaptations:
- Most structures and protein synthesis are in the cell body
- Dendrites receive signals to communicate with other nerves and muscles
- Axons are covered with a fatty sheath which speed up nerve impulses and transmit signals
sperm cell function and adaptation
Function - fertilise a female egg cell (ovum)
Adaptations:
- A lot of mitochondria to have a lot of energy to swim
- Flaggeum (tail) allows them to swim
- Stream-lined head to swim quickly
- Half chromosomes so that a full set of chromosomes can be restored during fertilisation
muscle cell function and adaptation
Function - contraction for movement
Adaptations:
- All muscle cells have protein filaments that slide over each other causing muscle contraction
- Many mitochondria release energy for muscle contraction
Compare the structure of a sperm cell and muscle cell
A sperm cell’s function is to travel through the fallopian tube to fertilise an ovum. They have a lot of mitochondria to travel efficiently to the egg whereas a muscle cell has a lot of mitochondria to have enough energy to contract. A muscle cell’s function is to contract and move. This means their structure has a lot of protein filaments that slide over each other in order to move. Sperm cells do not have protein filaments to move. Instead, they have a flaggeum (tail) to swim - muscle cells only need to move in one spot. Sperm cells also have half of their chromosomes so it can be fully restored when they fertilise whereas muscle cells have a full set.
