MCAT: Cell Biology Exam Questions and Answers

MCAT: Cell Biology Exam Questions and Answers Cell Theory - Correct Answer️️ -1) All living things are made of cells 2) Cell is the basic functional unit of life 3) Cells are formed from other cells 4) Cells contain DNA (genetic information) Are viruses living organisms? - Correct Answer️️ -No. They dont contain DNA (they have RNA), and they are not able to reproduce on their own (violates 3 and 4 of cell theory) Eukaryotic cells vs Prokaryotic cells - Correct Answer️️ -Eu: Nucleus. Pro: No nucleus Nucleus - Correct Answer️️ --contains all of the necessary information for replication -surrounded by the nuclear envelope that protects nucleus from cytoplasm Nucleolus - Correct Answer️️ --makes up 25% of the nucleus -rRNA synthesis Mitochondria - Correct Answer️️ --power plant of the cell, provides energy -outer membrane, inner membrane (cristae), intermembrane space, michondrial matrix -semi-autonomous - have their own DNA and can replicate through binary fision = cytoplasmic/extranuclear inheritance **RBCs don't have mitochondria - their only source of energy is from glycolysis Apoptosis - Correct Answer️️ --programmed cell death -mitchondria can do apoptosis, as well as lysosomes Lysosomes - Correct Answer️️ --have hydrolytic enzymes that can degrade substrates -autolysis Rough ER - Correct Answer️️ --has ribosomes -place of protein translation Smooth ER - Correct Answer️️ --no ribosomes -important for lipid synthesis, detoxification of drugs/proteins -transfer proteins from the RER to the Golgi Apparatus Golgi Apparatus - Correct Answer️️ --packages and modifies the proteins, then sends them to their corresponding cell part -if secretory proteins, packaged in secretory granules and released into the blood stream via exocytosis Peroxisomes - Correct Answer️️ --have H2O2 in them -very important in the B oxidation of fatty acids Cytoskeleton: 3 Parts - Correct Answer️️ -1) Microfilaments 2) Microtubules 3) Intermediate filaments Microfilaments - Correct Answer️️ --part of the cytoskeleton -primary protein is ACTIN -actin filaments can react with myosin for muscle contraction -also important in cytokinesis - the cleavage furrow is formed by actin filaments Microtubules - Correct Answer️️ --part of the cytoskeleton -primary protein is TUBULIN -cilia and flagella made of microtubules - 9+2 pattern -centrioles (form the mitotic spindles) - 9 triplets -where motor proteins like kinesin and dynein walk on Intermediate Filaments - Correct Answer️️ --part of cytoskeleton -important for cell-cell adhesion, anchor organelles, makes the cell rigid ex- keratin, lamin 4 types of tissue - Correct Answer️️ -1) Epithelial 2) Nervous 3) Connective 4) Muscle Epithelial Tissue - Correct Answer️️ --covers the bodies, lines its cavities -epithelial cells are tightly joined together and to an und