BIOL 101 Exam 2 Study Guide, Fall 2023

Flashcards based on key terms and concepts from the lecture notes for BIOL 101 Exam 2.

Cell Theory

1. All organisms are composed of cells. 2. Cells are the basic unit of structure and function in an organism. 3. All cells come from preexisting cells.

Prokaryotic Cells

Single-celled organisms without a nucleus or membrane-bound organelles. Examples include bacteria and archaea.

Eukaryotic Cells

Organisms containing a nucleus and membrane-bound organelles. Include multicellular organisms like plants, animals, and fungi, as well as unicellular organisms like amoeba.

Endosymbiotic Theory

Explains how eukaryotic cells arose from prokaryotic cells; involves one cell consuming another for beneficial functions.

Nucleus

Contains most of the cell's DNA; surrounded by the nuclear envelope, has nuclear pores for transport, and includes chromatin and nucleolus.

Ribosomes

Organelles that synthesize proteins; can be free (in cytosol) or bound (to rough endoplasmic reticulum).

Endomembrane System

Collection of membranes involved in protein synthesis, transport, metabolism of lipids, detoxification, and cellular waste removal.

Golgi Apparatus

Functions as the cell’s 'post office'—receives, processes, and ships cellular products.

Lysosomes

Sacs of enzymes that digest macromolecules; found only in animal cells.

Vacuoles

Storage sacs found in cells, significant in plants and fungi for various functions including turgor pressure.

Mitochondria

Energy-producing organelles involved in cellular respiration, converting sugars and fats into ATP.

Chloroplasts

Organelles responsible for photosynthesis; convert solar energy into chemical energy.

Cytoskeleton

Network of protein fibers providing structural support and transport within the cell; includes microtubules, microfilaments, and intermediate filaments.

Cell Wall

Protective layer external to the plasma membrane, found in plant cells, prokaryotes, fungi, and some protists.

Plasma Membrane

Selectively permeable barrier that regulates transport into and out of the cell.

Fluid Mosaic Model

Describes the plasma membrane as flexible with varied components allowing movement and function.

Phospholipids

Key component of plasma membranes, amphipathic with hydrophilic heads and hydrophobic tails.

Active Transport

Movement of substances against their concentration gradient, requiring energy, usually in the form of ATP.

Diffusion

Movement of molecules from an area of high concentration to an area of low concentration.

Osmosis

Diffusion of water across a selectively permeable membrane.

Tonicity

The solute concentration of a solution surrounding a cell, affecting water movement and cell shape.

Metabolism

The sum of all chemical reactions within an organism, including catabolism and anabolism.

ATP (Adenosine Triphosphate)

Energy-carrying molecule that drives cellular activities; produced during cellular respiration.

Enzymes

Biological catalysts that speed up reactions by lowering activation energy.

Photosynthesis

Process converting light energy into chemical energy stored in sugars; occurs in chloroplasts.

Cellular Respiration

Process of breaking down organic molecules to produce ATP; includes glycolysis, citric acid cycle, and oxidative phosphorylation.

Fermentation

Anaerobic process that allows glycolysis to continue by recycling NAD+, producing less ATP.

Redox Reactions

Chemical reactions involving the transfer of electrons; include oxidation (loss of electrons) and reduction (gain of electrons).

Electrogenic Pump

Transport proteins that generate voltage across a membrane, such as the sodium-potassium pump.