3.2.1 Cell Structure Flashcards
What are the inner folds of mitochondria called?
Cristae
What is the function of the Golgi Apparatus?
To process & package new proteins & lipids; makes lysosomes.
What is the function of a lysosome?
Contain enzymes- lysozymes used to digest broken/invaded cells.
What is a ribosome made of?
Proteins, RNA
What is the function of a ribosome?
Protein synthesis
Describe the difference between smooth & rough endoplasmic reticulum.
Smooth= no ribosomes
What is the function of the smooth ER?
Synthesises & processes lipids
What makes up the cell wall of plants & algae?
Cellulose
What is a tonoplast?
The membrane of a vacuole
Why would an epithelial cell in the small intestine need lots of mitochondria?
Respiration, to give energy needed for absorption of nutrients by active transport
What is a tissue?
A group of similar cells performing a similiar function e.g. epithelial cells form epithelial tissue
What is an organ?
A group of similar tissues working together e.g muscular, epithelial & glandular tissues form the stomach.
Describe the function of the nucleolus.
Makes ribosomes
Give 2 differences between plant & fungal cells.
Fungi= no chloroplasts & chitin cell wall not cellulose
List 3 differences between eukaryotic & prokaryotic cells.
Prokaryotic = no membrane bound organelles, no nucleus, smaller ribosomes, murein cell wall
What is a plasmid?
A loop of DNA NOT part of main chromosomal DNA e.g. genes for antibiotic resistance. Not in all bacterial cells.
Why might a bacterial cell have a slime capsule?
To give protection against the cells of the immune system, to stop too much water leaving the cell and to protect against antibiotics
Why do prokaryotes undergo Binary Fission?
Bacteria replicate using binary fission
What replicates in Binary fission?
Chromosomal DNA replicates once- plasmids may replicate many times
What is the role of the attachment proteins of a virus?
To allow viruses to invade host cells, by using complemetary binding to receptors on host cells.
Briefly describe the steps of viral replication.
- Viruses attach to host cells using attachment proteins 2. Genetic material is released into host cell 3. Host cell machinery replicates viral DNA/RNA/proteins 4. Viruses assemble & replicate 5. Viruses leave host cell
Describe the term resolution.
Level of detail seen in an image- how close together 2 objects are to be seen as separate.
Describe the term magnification.
The number of times larger an image of an object is compared with the actual size.
Describe 2 differences between a light microscope & SEM.
SEM- higher resolution (3-10nm rather than 200nm), higher magnification (200,000 rather than 2000), uses electrons rather than light, can see surface of cells- 3D image
Write down the formula for magnification.
magnification = size of image/ size of real object
1mm = ? μm
1mm = 1000 μm
50 μm = ? cm
0.005 cm
1mm = ? nm
1mm = 1,000,000m
Use standard form to write the number 0.00002 mm
2 x 10-5
List 3 organelles you cannot view with a light microscope.
ribosomes, ER, lysosomes
Describe when you would use a TEM.
To view a thin specimen, high resolution to see small objects.