exam_2_study_guide_

Prokaryotic Cell Structure

Lacks a nucleus, has a single DNA strand, and few membrane-bound organelles.

Plasmids

Small circular DNA molecules that carry genetic information.

Ribosomes

Protein manufacturing centers that translate RNA into proteins.

Cytoplasm

The jelly-like substance inside the cell that contains all components.

Eukaryotic Cell Structure

Contains a nucleus, multiple organelles, and is generally larger than prokaryotic cells.

Nucleus

Contains the genetic material and is surrounded by a double membrane.

Rough ER

Endoplasmic reticulum with ribosomes, involved in protein synthesis.

Smooth ER

Involved in lipid synthesis and detoxification processes.

Lysosomes

Organelles that contain enzymes to break down macromolecules.

Vacuoles

Storage sac in plant and fungal cells for nutrients and waste.

Mitochondria

The powerhouse of the cell, generates ATP, has its own DNA.

Chloroplast

Site of photosynthesis in plant cells, contains its own DNA.

Microtubules

Filaments that create tracks for movement of organelles within cells.

Microfilaments

Filaments involved in muscle contraction and cellular movement.

Intermediate Filaments

Provide structural stability to the cell.

Cell Junctions

Structures that facilitate communication and adhesion between cells.

Types of Cell Junctions

Include tight junctions, desmosomes, gap junctions, and plasmodesmata.

Signal Reception

Initial step in cell signaling where a protein changes shape after binding a signal molecule.

Signal Transduction

Process where a signal is relayed through secondary messengers inside the cell.

Signal Response

The cellular outcome of a signal which could be to activate or inhibit processes.

Signal Deactivation

Process to stop responses, often involving GTP hydrolysis or phosphatases.

Lipid-Soluble Molecules

Diffuse across cell membranes and bind to intracellular receptors.

Lipid-Insoluble Molecules

Bind to transmembrane receptors triggering a signaling pathway.

Glycolysis

The first step of cellular respiration occurring in the cytosol, breaking down glucose.

Citric Acid Cycle

Occurs in the mitochondrial matrix, generates NADH and FADH2.

Oxidative Phosphorylation

Final stage of cellular respiration that produces ATP using the electron transport chain.

Fermentation

Anaerobic process that regenerates NAD+ to sustain ATP production.

ATP Production in Glycolysis

Requires an initial investment of 2 ATP but results in a net gain of 2 ATP.

Electron Transport Chain

Series of proteins that transfer electrons to produce ATP using a proton gradient.

Photosynthesis

Process used by plants to convert light energy into chemical energy.

Light Reactions

Convert light energy into chemical energy (ATP and NADPH) using water.

Calvin Cycle

Uses ATP and NADPH to convert carbon dioxide into glucose.

Photosystems

Structures in thylakoids that capture light energy for photosynthesis.

Cyclic Electron Flow

Electron cycle in photosynthesis that generates ATP without producing NADPH.

Noncyclic Electron Flow

Flow of electrons that produces both ATP and NADPH in photosynthesis.

Rubisco

Enzyme that catalyzes the first step of the Calvin cycle but can also fix oxygen.

C3 Plants

Plants that utilize the standard Calvin cycle for carbon fixation.

C4 Plants

Plants that use PEP carboxylase for initial carbon fixation, transporting products to rubisco.

CAM Plants

Plants that fix CO2 at night and use it during the day for photosynthesis.

Oxidizing Agent

Substance that causes another atom to lose electrons.

Reducing Agent

Substance that donates electrons to another atom.

Activation Energy

The minimum energy required for a reaction to occur.

Free Energy Diagram

Graphical representation illustrating the energy changes during a reaction.

Enzyme Catalysis Steps

Include initiation, lowering activation energy, and product release.

Chemical Reaction Spontaneity

Determined by changes in enthalpy (ΔH) and entropy (ΔS).

Transport Vesicles

Membrane-bound sacs that transport proteins and other materials within the cell.

G Protein-Coupled Receptors

Receptors that activate G proteins for signal transduction.

Hormonal Signaling

Communication process using hormones as signals to regulate cellular functions.

Phosphorylation Cascade

A series of reactions where one kinase activates another through phosphorylation.

Autophagy

Cellular process that degrades and recycles cellular components.

Cellular Respiration Inputs and Outputs

Includes glycolysis, citric acid cycle, and oxidative phosphorylation producing ATP.