Lecture 3.1 Flashcards
Essential Components of Animal Cells; describe the purposes of:
1) Nucleus
2) Ribosomes
3) Mitochondria (name 2 specific aspects)
1) DNA storage, transcription and synthesis, mRNA processing
2) Translation
3) Energy production; apoptosis
-Oxidative phosphorylation
-Cytochrome C
Essential Components of Animal Cells; describe the purposes of:
1) ER (for each of the two parts)
2) Golgi
3) Lysosomes
1) -Rough and smooth: Rough folds and processes proteins
-Smooth produces lipids
2) Modifies proteins for transportation
3) Digestive enzymes for macromolecules: Protein, polysaccharides, lipids, nucleic acids
Essential Components of Animal Cells; describe the purposes of:
1) Proteosomes
2) Peroxisomes
3) Cytoskeleton
4) Plasma membrane
1) Degrade proteins
2) Oxidative enzymes for long chain fatty acid metabolism
3) Cell shape, polarity (orientation), organization and movement of organelles, cell motility
4) Regulated movement of solutes, cell-to-cell interaction
What are the 3 ways lysosomes/ proteasomes are formed?
1) Through pinocytosis or receptor mediated endocytosis
2) Phagocytosis – microorganisms are engulfed to form phagosome
3) Autophagy – large proteins and organelles are surrounded by ER membrane and “fed” to the lysosome
What is the job of proteasomes?
Denatured or misfolded proteins are tagged with “ubiquitin” then disassembled here
How many different hydrolases are there to tear stuff apart?
40
1) What’s permeable to the plasma membrane?
2) What’s impermeable?
1) Very small particles, non-polar particles
-Water, O2, CO2, ethanol, steroids, vit D
2) Polar particles, large particles
-Proteins, glucose, ions
List the 4 primary ways to get through the plasma membrane
1) Passive transport
2) Active
3) Endocytosis
4) Phagocytosis
1) Passive transport: which method is fast and which is slow?
2) What mediates this?
1) Channels (fast), carriers (slow)
2) Receptors
What are the two types of endocytosis?
1) Caveolae mediated - “little cave”
2) Receptor mediated – clathrin; LDL and transferrin
What is responsible for the synthesis of transmembrane proteins and lipids?
ER/ golgi
Rough ER:
1) _______________ molecules ensure protein is properly folded.
2) Excess accumulation of misfolded proteins leads to what? What does this cause?
1) Chaperone
2) Unfolded protein response; apoptosis
Smooth ER:
1) What does it synthesize?
2) What does it catabolize?
3) What does it store?
1) Steroids (gonads and adrenals)
2) Lipid-soluble molecules (liver)
2) Calcium (muscle “sarcoplasmic reticulum”)
Golgi apparatus:
1) What does it do?
2) What added to proteins in the ER are modified here?
1) Packaging to organelles or plasma membrane
2) N-linked oligosaccharide
Mitochondria’s cytochrome C is involved in what?
Apoptosis
What are the 2 types of receptors?
Extracellular + intracellular
1) Thing that “lands” on a receptor is called what?
2) What are the two things this thing can do?
1) A ligand
2) -Either initiate a second messenger system to start intracellular functions
Or
-It can interact directly with DNA and affect transcription
List 4 types of receptors
1) Receptor tyrosine kinases (RTKs)
2) Kinase activity
3) G-protein coupled receptors
4) Steroids
1) True or false: DNA-binding domains permit specific binding to short DNA sequences
2) Sometimes transcription factors bind in what region?
1) True
2) Promoter
1) Sometimes transcription factors bind to what long-range regulatory elements? What do these do?
2) What are elements?
1)”Enhancers”; though far away, “loop back” to interact with the genes they regulate
2) Pieces of DNA
Growth Factors:
1) What do they do?
2) How do they do this?
3) What do they prevent?
1) Promote entry of cells into the cell cycle; promote replication
2) Enhance biosynthesis of cellular components
Nucleic acids, proteins, lipids, carbohydrates
Done to provide the machinery necessary to create daughter cells
3) Apoptosis
List 2 growth factors involved in regeneration and repair
1) Epidermal growth factor (EGF)
2) Vascular endothelial growth factor (VEGF)
1) What do totipotent stem cells do?
2) What can adult stem cells do?
1) Give rise to all types of differentiated tissues
2) Only have capacity to replace damaged cells of the same type
1) What type of medicine uses stem cells to heal patients?
2) Why is this difficult?
1) Regenerative medicine
2) Difficulty lies in implanting cells in patients that remain located at site of damage