2.1 Cells Flashcards
What is magnification?
The number of time’s larger an image appears compared to its real size
What is resolution?
The clarity of an image and the ability to distinguish between two points
What is the formula for magnification?
Magnification=
Image size/real size
Which microscope can produce a 3D image of the surface of a specimen?
Scanning electron microscope
Which microscope can produce an image of a thin specimen?
Transmission electron microscope
What is the maximum resolution and magnification of a light microscope?
Res: 0.2um
Mag: x1500
What is the maximum resolution and magnification of a transmission electron microscope?
Res: 0.0002um
Mag: xMillion
Why can a laser scanning confocal microscope produce a much clearer image than a light microscope?
The laser is focused through a pinhole, which blocks any out of focus light
Why might you use differential staining?
To identify different cellular components and cell types, and help them stand out from the background
What is the function of the nucleus?
- Stores genetic information
- Control centre of the cell
What is the function of the nucleolus?
It makes ribosomes
What is the function of the nuclear envelope?
Nuclear envelope separates the contents of the nucleus from the rest of the cell. It is a double membrane
What is the function of the nuclear pores?
They allow larger substances such as mRNA to leave the nucleus
What is the function of the rough endoplasmic reticulum (RER)?
Folds and processes proteins that have been made at the ribosomes
What is the function of the smooth endoplasmic reticulum (SER)?
Makes and processes lipids
What is the function of the golgi apparatus?
- Processes and packages lipids and proteins
- Makes lysosomes
What is the function of mitochondria?
Site of aerobic respiration and ATP production
What is the function of chloroplasts?
Site of photosynthesis
What is the function of a vacoule?
When filled with water it makes the plant cell turgid, which gives the plant stability
What is the function of a lysosome?
- Keeps digestive enzymes separate from the rest of the cell
- Digest invading cells or old organelles
What is the function of cillia?
- Acts as an antenna, containing receptors
- Sweeps mucus in epithelial cells
- Moves sperm cells
What is the function of ribosomes?
Protein synthesis
What forms cillia?
Centrioles
What is the difference between prokaryotic and eukaryotic DNA?
Prokaryotic is circular and free in cytoplasm but Eukaryotic is linear and encased in nucleus.
Where are extracellular proteins made?
Ribosomes on rough endoplasmic reticulum
Where are intracellular (cytoplasm) proteins made?
Free ribosomes in cytoplasm
What does the RER do in protein synthesis?
Make proteins, then fold and process them
How is the cytoskeleton arranged in eukaryotes?
Protein threads arranged as microfilaments and microtubules.
What are microfilaments?
Small solid strands of protein threads
What are microtubules?
Tiny protein cylinders
What keeps cell organelles supported and in position?
Cytoskeleton
What can prevent the cytoskeleton from functioning and why?
Respiratory inhibitors, as their movement requires ATP from respiration
What can cause a cell to move?
Cytoskeleton
What is the difference between prokaryotic and eukaryotic cell walls?
Eukaryotic made from either cellulose or chitin, prokaryotic not
