MCAT Biology

Bio Section

262 cards   |   Total Attempts: 188
  

Cards In This Set

Front Back
Prokaryotes
Unicellular with simple structureNo true nucleusnucleoid with DNAPlasmids30S and 50S RibosomesNo Membrane Bound Organelles
Eukaryotes
Nucleus w/ DNA in chromosome40S and 60S ribosomesMembrane bound organelles
Cell Membrane
Answer 3
Phospholipid bilayerSelective Permeability: Small, nonpolar but not charged ions or large moleculesCAMS: cell adhesion moleculesRecepotrs: complex proteins on surface that bind molecules in environment
Nucleus
Answer 4
Nuclear membraneNuclear poresNucleolus - where rRNA synthesis occurs
Ribosomes
Site of protein production2 subunitsFree : in CytoplasmBound : in ER
Endoplasmic Reticulum
Network of Membrane Enclosed spaces connected with nuclear membraneRough ER: ribosomes- Makes proteins and intracellular TransportSmooth ER: no ribosomes- Lipid synthesis and Detox
Golgi Apparatus
Receives vesicles and contents from SERModifies + Packages into vesiclesDistributes them
Lysosomes
Membrane bound vesicles with hydrolytic enzymesmax effectivity at pH5 (why it needs to be enclosed)break down old componentsAutolysis - rupturing lysosome membrane -> release hydrolytic enzymes
Microbodies
Containers for metabolic rxnsPeroxisomes - have oxidative enzymes involving hydrogen peroxideGlyoxysomes - convert fats into sugars until seedling is mature enough to produce its own sugars
Mitochondria
Answer 10
Site of aerobic respiration(Inheritance from oocyte)semiautonomous - has its own DNA and ribosomesIntermembrane space, Cristae (the convolutions) and Matrix (inner part, where many reactions occur)
Centrioles
Specialized type of microtubule involved in spindle organization during cell divisionPlants don't have centriolesAnimals have a pair of centrioles oriented at right angles to each other in the centrosomeComposed of microtubules
Cytoskeleton: Microtubule
Hollow rods of tubulin. Provides framework for organelle movement in the cell.
Cytoskeleton: Microfilaments
Solid rods of actin invovled in cell movement and support(e.g. Muscle contraction actin-myosinmove materials across plasma membrane
Cytoskeleton: Intermediate filaments
Involved in maintenance of cytoskeletal integrity
Simple Diffusion
Net movement of particles down their concentration gradients (Passive)Osmosis - Water from low to high solute concentration