Organelles Flashcards
Name 4 functions of the cytoplasm
- Contains cell organelles
- Transport medium
- Fatty acid synthesis
- Metabolism of carbohydrates (glycolysis), amino acids and nucleotides using enzymes
Name 2 functions of lysosomes, and what are lysosomes rich in? Name a cell type that will have many lysosomes?
- Cellular digestion
- Detoxification & removal of waste
- Hydrolytic enzymes e.g. Proteases
- Macrophages - phagocytic
Name 3 functions of Golgi in preparing proteins from the RER?
- Modifying
- Sorting
- Packaging ready for export
What is the function of mitochondria?
ATP synthesis via Krebs Cycle
Oxidative phosphorylation
What is the major role of smooth ER, and what two kinds of cells may have an abundance of smooth ER?
- Lipid/steroid synthesis
- Adipocytes and Steroidogenic cells e.g. In gametes
What happens in the Rough ER? How does the product travel to the Golgi?
- Protein synthesis
- Pinched off in vesicles towards Golgi
Name 3 important functions of the nucleus.
- Contains cell genetic material
- DNA synthesis and repair occurs here
- Transcription (mRNA synthesis for protein synthesis) occurs here
What are two functions of the plasma membrane?
- Selective import/export of molecules to protect integrity of cell
- Cell morphology
What occurs on ribosomes? Why are there only a few types of ribosomal DNA but lots of types of mRNA?
- Protein synthesis using mRNA and tRNA on the rough ER
- Because ribosomes are the units which under control of tRNA form polypeptide chains. They have a distinct function so have limited types. mRNA is used to make 1000s different proteins for cell life, so a different mRNA is needed for each of those proteins.
Name 7 functions of plasma membrane S T E E I I S
Selective Permeability Transport of materials along cell surface Endocytosis Exocytosis Intercellular adhesion Intercellular recognition Signal Transduction
What is the limit of resolution?
The point at which two points can no longer be seen as separate. ie. they appear as one structure
What are 3 differences between Eukaryotic and Prokaryotic (e.g. Bacterial) cells?
Prokaryotic cells have no separate nucleus
They have a cell wall and plasma membrane
They lack most organelles
Do prokaryotic or eukaryotic cells have internal membranes?
Eukaryotic
How is a phospholipid molecule made up and what does amphipathic mean?
Hydrophillic phosphate head, hydrophobic fatty acid tail and it means it is both hydrophobic and phillic
What is the glycocalyx?
Cell coat made up of oligosaccharides and polysaccharides
What is the difference between where free ribosomes and ER ribosomes release proteins to?
Free - cytoplasm
Bound - into ER lumen
________ (which organelles) fuse with material requiring digestion
Lysosomes
How are lysosomes formed?
Late endosomes (from endocytosed material) + Phagosomes + Autophagosomes
What do peroxisomes do?
Detoxify (oxidise) a number of chemicals e.g. Alcohol
What is different about Mitochondrial DNA/division
It is similar to bacterial and divides on it’s own genetic information - not held in nucleus. It’s lineage is female
What do microfilaments, intermediate filaments and microtubules make up? Whats its role? What are microfilaments/intermediate filaments?
Make up cytoskeleton
Microfilaments - actin
Intermediate - can be different things e.g. Keratin
Microtubules
Role in cell shape, strength, mitosis/meiosis, transport around cell. movement.
What are microtubules made of?
Tubulin - hollow cylinders found where structures move e.g. Mitosis spindle/cilia/flagella
What is the arrangement of microtubules in cilia/flagella?
9+2 (2 in middle of circle). Dyanin arms round the circle.
What are autophagosomes vs phagosomes vs endosomes?
Endo - endocytosed material
Phagosomes - phagocytosed material
Autophagosomes - intracellular vesicular material aimed for lysosomes etc to degrade
