Cell Biology and Metabolism Review

Flashcards covering key vocabulary terms related to cell biology, DNA, RNA, protein synthesis, cell division, membrane transport, metabolism, and enzyme function, based on lecture notes.

Plasma membrane

A fluid, oily 'thing' that encloses the cell and makes up the cell membrane.

Mitochondria

An organelle that uses oxygen to create ATP through aerobic respiration.

Rough Endoplasmic Reticulum

An organelle with ribosomes for protein synthesis, where proteins enter its lumen and are moved to other organelles.

Smooth Endoplasmic Reticulum

An organelle containing enzymes for fatty acid and steroid synthesis, and which stores and releases calcium.

Golgi Apparatus

Often called the 'UPS of the cell,' it sends 'packages' outside the cell or brings 'packages' in.

Cytoskeleton

Composed of microfilaments, intermediate filaments, and microtubules, providing structural support to the cell.

Microfilaments

The smallest components of the cytoskeleton, made from actin.

Intermediate filaments

Components of the cytoskeleton made from various different proteins.

Microtubules

Components of the cytoskeleton made of Alpha & Beta Tubulin, having positive and negative ends.

Kinesin

A motor protein that carries a vesicle towards the positive end of microtubules.

Nucleus

An organelle enclosed by a double membrane that stores DNA, where mRNA passes between it and the cytoplasm through nuclear pores.

Nucleolus

The site of ribosomal RNA synthesis within the nucleus.

Chromosomes

Structures found in the nucleus, consisting of 22 autosomal pairs and one pair of sex chromosomes.

Nucleosome

A 'hair curler' for DNA that packs DNA into a mitotic chromosome.

Transcription

The process of creating RNA from a DNA template.

Intron

A part of pre-mRNA that is removed during RNA modification (the part you don't want).

Translation

The process of converting mRNA into proteins.

Codons

Three-nucleotide sequences on mRNA that specify which amino acids are used to make proteins.

AUG

The START codon in protein synthesis.

UGA, UAA, UAG

The primary STOP codons in protein synthesis.

DNA Bases

Adenine (A), Cytosine (C), Thymine (T), Guanine (G), with Uracil (U) replacing Thymine in RNA.

Mitosis

A type of cell division resulting in two identical daughter cells (clones), typically involving stages PMAT: Prophase, Metaphase, Anaphase, Telophase.

Meiosis

A type of cell division that results in four daughter cells, each with half the number of chromosomes of the parent cell, involving two rounds of division.

Chiasmata

The points where exchange occurs between chromatids during meiosis.

Facilitated Diffusion

A process that allows substances to cross the cell membrane by utilizing specific protein channels or protein carriers.

Gated channels

Protein channels that are triggered to open in response to a specific stimulus, used in facilitated diffusion.

Primary Active Transport

A type of transport where carrier proteins within the membrane become phosphorylated as energy is released from ATP molecules, often moving ions against their gradient.

Secondary Active Transport

A type of transport that couples the movement of one substance following its concentration gradient to move another substance against its gradient.

Exergonic reaction

A metabolic reaction where reactants end with less energy than they started, e.g., cell respiration, catabolism.

Endergonic reaction

A metabolic reaction that consumes chemical energy, e.g., active transport, cell movement.

Enzymes

Proteins that act as biological catalysts, lowering activation energy and increasing the rate of a reaction without being changed themselves.

Active site

The specific region on an enzyme where the substrate binds.

Substrate

The molecule upon which an enzyme acts.

Enzyme-Substrate complex

The temporary molecule formed when an enzyme binds to its substrate.

Saturation (Enzyme Kinetics)

The maximum rate at which catalyzed reactions can occur when all enzyme active sites are occupied by substrate.

Catalase

An enzyme that catalyzes the reaction 2 H2O2 -> 2 H2O + O2.

Amylase

An enzyme that catalyzes the reaction Starch + H2O -> Maltose.

Carbonic anhydrase

An enzyme that catalyzes the reaction H2CO3 -> H2O + CO2.

Lactate dehydrogenase

An enzyme that catalyzes the reaction Lactic acid -> Pyruvic acid + H2.

Ribonuclease

An enzyme that catalyzes the reaction RNA + H2O -> Ribonucleotides.

Enzyme Activity Control

The regulation of enzyme function, sensitive to factors such as temperature, pH, substrate concentration, and stimulatory or inhibitory effects.

Aerobic respiration

Cellular respiration that uses oxygen to completely oxidize glucose, producing H2O, CO2, and a net of 32 ATP.

Anaerobic respiration (Fermentation)

Metabolic processes that occur in the absence of oxygen, involving incomplete oxidation of glucose, producing organic compounds (like lactate or alcohol) and CO2, with a net gain of 2 ATP.

Oxidation

A chemical process where a compound loses electrons.

Reduction

A chemical process where a compound gains electrons.

NAD+

An electron transporter that turns into NADH when reduced, important in energy-producing metabolic pathways.

Glycogen

The storage form of glucose, primarily found in the liver.