Cell Structure 1 - Victor Flashcards
What are 4 types of tissue?
Nervous, epithelial, connective, muscle
Cell -> _____ -> Organ -> ______
Tissue, Organ System
Assign ectoderm, endoderm and mesoderm to these 4 types of tissue:
- Nervous
- Epthelial
- Connective
- Muscle
- Nervous (ectoderm)
- Epithelial (ectoderm, endoderm and mesoderm)
- Connective (mesoderm)
- Muscle (mesoderm)
What is the cytoskeleton’s function?
Mechanical shape, anchors organelles/maintains spacial organization, transport of materials.
Where are ribosomes made?
Nucleolus.
What is a common lipid:protein ratio of plasma membranes?
1:1. 3:1 for neurons.
What does amphipathic mean?
Contains polar and nonpolar regions. “Path”etic polar bears.
Do cell membranes typically allow lateral diffusion of proteins?
Yes.
What kinds of molecules are membranes permeable to? Impermeable to?
Permeable to nonpolar molecules (N2, O2) small polar molecules (H2O). Impermeable to charged ions.
What are 3 general functions of membrane proteins?
Signaling, transport, adhesion.
T or F. Glycolipids are located on the inner leaflet.
False. Glycolipids are only located on the outer leaflet.
What are the 4 parts of a phospholipid?
- Amino alcohol
- Phosphate
- Glycerol
- Fatty acids
What prevents packing of the phospholipid tails?
One tail is often unsaturated, causes kink.
What are the 3 parts of cholesterol?
- Polar head group
- Steroid rings
- Nonpolar hydrocarbon tail
Name 4 ways cholesterol can affect plasma membranes.
- Provides mechanical strength
- Buffers membrane fluidity (membrane fluidity plateaus when you add high amounts of cholesterol)
- Reduces permeability to small molecules
- Contributes to lipid rafts
How does a glycolipid differ from a phospholipid?
Instead of amino alcohol + phosphate, it has sugar.
What is glycocalyx?
Sugar coating on most cells. Made of oligosaccharides and proteoglycans.
T of F. Glycolipids are found on the outer leaflet.
True, glycolipids are only found on the outer leaflet.
Tay Sachs is a defect in __________.
Ganglioside (a glycolipid) metabolism.
What is the P face and E face?
P (protoplasmic) face: inner leaflet of plasma membrane.
E (extracellular) face: outer leaflet.
When you fracture a leaflet, which face do the integral proteins typically stay on?
Proteins stay on the P face (anchored on cytoplasmic side). E face is left “hole” lol im lame.
The carbs of the glycocalyx come from what 2 sources?
- associated with Glycolipids
2. associated with proteins
What is the function of the glycocalyx?
Strong negative charge blocks infection (opsonized bacteria is covered with negatively charged Ab)
Protection from chemical and mechanical damage.
Cell to cell recognition (carbs can be markers for certain cells)
T or F. Movement of ions and small molecules (Na, K, glucose) across cell membranes is facilitated by transport proteins.
True.
T of F. Movement of macromolecules and particulate matter is controlled by endo/exocytosis.
False. Jk True.
Name 3 types of endocytosis.
- Pinocytosis (cell drinking)
- Receptor mediated endocytosis
- phagocytosis
Pinocytosis: bulk fluid uptake into ______ coated endocytic vesicles.
Clathrin.
Pinching off of vesicle driven by collar of GTPase protein called _______.
Dynamin.
T or F. Vesicles in capillary endothelial cells fuse with lysosomes.
F. Vesicles usually fuse with lysosomes first, but in this case, vesicles fuse directly with membrane (transcytosis).
Endosome + lysosome = __________
Secondary lysosome.
T of F. Phagocytosis is generally restricted to macrophages and neutrophils.
True.
T or F. Endocytosis and phagocytosis are clathrin mediated.
False, phagocytosis is actin mediated.
What is a phagosome?
Large vesicle with engulfed material.
Name 2 functions of exocytosis.
Replace membranes, secrete materials.
Name an example of constitutive exocytosis.
Mucous secretion.
Name an example of regulated exocytosis.
Release of zymogen granules.
