Unit 1 Study Guide

Activation Affinity

The strength of the interaction between a substrate and an enzyme.

Amino Acid

Organic compounds that serve as the building blocks of proteins.

Anabolism

The metabolic process that builds up molecules by forming larger compounds from smaller units.

ATP

Adenosine triphosphate, the primary energy carrier in living organisms.

Carbohydrate

A biological macromolecule made of sugar molecules that provides energy.

Catabolism

The metabolic process that breaks down molecules into smaller units, releasing energy.

Catalysis

The acceleration of a chemical reaction through the use of a catalyst.

Cilia

Microscopic, hair-like structures that extend from the surface of many eukaryotic cells.

Competition

The interaction between organisms that vie for the same resources in an ecosystem.

Connective Tissue

Tissue that supports, binds together, and protects tissues and organs in the body.

Cytoplasm

The gel-like substance inside a cell, excluding the nucleus, where cellular processes occur.

Cytoskeleton

A network of protein filaments and tubules that provides structure and shape to a cell.

Cytosol

The liquid component of the cytoplasm, where organelles are suspended.

Diffusion

The movement of molecules from an area of higher concentration to an area of lower concentration.

DNA

Deoxyribonucleic acid, the molecule that carries the genetic information of an organism.

Effector

A molecule or protein that interacts with a target, producing a physiological response.

Electron Transport Chain

A series of protein complexes that transfer electrons, creating a proton gradient to produce ATP.

Endocrine

Relating to glands that secrete hormones directly into the bloodstream.

Endocytosis

The process by which cells internalize substances from their external environment.

Endoplasmic Reticulum

An organelle involved in the synthesis of proteins and lipids.

Energy

The capacity to do work, which is essential for all cellular processes.

Enzyme

A biological catalyst that speeds up chemical reactions in living organisms.

Epithelial Tissue

A type of tissue that covers the body's surfaces and lines cavities and organs.

Epithelium

A layer of cells forming the outer surface of an organ or the inner lining of a cavity.

Exchange

The process by which two or more entities engage in reciprocal transactions.

Excitable Tissue

Tissues, such as muscle and nervous tissue, that can generate and propagate electrical signals.

Exocrine

Glands that secrete substances through ducts to the exterior or into the digestive system.

Exocytosis

The process by which cells expel materials in membrane-bound vesicles.

Fatty Acid

A carboxylic acid with a long aliphatic chain, important for energy storage.

Feedback

The process by which systems respond to changes in their environment.

Fermentation

A metabolic process that converts sugar to acids, gases, or alcohol in the absence of oxygen.

Flagella

Long, whip-like structures that aid in the movement of cells.

Glucose

A simple sugar and primary energy source for cells.

Glycerol

A three-carbon molecule that forms the backbone of lipids.

Glycolysis

The metabolic pathway that converts glucose into pyruvate, generating ATP.

Glycosidase

An enzyme that catalyzes the hydrolysis of glycosidic bonds.

Golgi Apparatus

An organelle that modifies, sorts, and packages proteins and lipids for secretion.

Homeostasis

The process by which an organism maintains a stable internal environment.

Inhibition

The process of decreasing or suppressing a biological function.

Integration

The process of combining different components to create a unified whole.

Interstitial Fluid

Fluid that surrounds tissue cells, providing a medium for nutrient and waste exchange.

Intracellular Fluid

The liquid found inside cells, containing various substances and organelles.

Junction Proteins

Proteins that facilitate cell-to-cell communication and adhesion.

Kreb’s Cycle

A series of chemical reactions used by all aerobic organisms to generate energy.

Lipase

An enzyme that catalyzes the breakdown of fats.

Lipid

A group of hydrophobic biomolecules, including fats and oils, vital for energy storage.

Lumen

The inside space of a tubular structure, such as a blood vessel or a hair follicle.

Lysosome

An organelle containing digestive enzymes to break down waste materials.

Macromolecule

Large, complex molecules, such as proteins, lipids, and nucleic acids.

Mass Balance

The principle stating that mass cannot be created or destroyed in a closed system.

Membrane

A selectively permeable barrier that separates cellular compartments.

Metabolism

The sum of all chemical reactions that occur within a living organism.

Microvilli

Tiny projections that increase surface area for absorption in epithelial cells.

Minerals

Inorganic substances essential for various bodily functions.

Mitochondria

Organelles known as the powerhouse of the cell, generating ATP through respiration.

Monosaccharide

The simplest form of carbohydrate, consisting of a single sugar unit.

Motor Proteins

Proteins that generate movement in cells and muscle contraction.

NAD

Nicotinamide adenine dinucleotide, a coenzyme involved in redox reactions.

Neural Tissue

Tissue composed of neurons and supporting cells, responsible for transmitting signals.

Nucleic Acid

Biomolecules that store and transmit genetic information, such as DNA and RNA.

Nucleotide

The building block of nucleic acids, consisting of a sugar, phosphate, and a nitrogenous base.

Nucleus

Organelle that houses an organism's genetic material.

Organ

A collection of tissues that perform a specific function within an organism.

Osmosis

The diffusion of water across a selectively permeable membrane.

Permeability

The ability of a membrane to allow substances to pass through it.

Phagocytosis

The process by which cells engulf large particles or other cells.

Phospholipid

A molecule composed of glycerol, two fatty acids, and a phosphate group, forming cell membranes.

Physiology

The study of the normal functions of living organisms and their parts.

Plasma

The liquid component of blood that carries cells and nutrients.

Polypeptide

A long chain of amino acids linked by peptide bonds.

Polysaccharide

A complex carbohydrate made of multiple sugar units.

Protease

An enzyme that breaks down proteins into smaller peptides or amino acids.

Protein

Large biomolecules made from amino acids, essential for structure and function.

Proteolysis

The breakdown of proteins into smaller polypeptides or amino acids.

Ribosome

Molecular machines that synthesize proteins by translating mRNA.

RNA

Ribonucleic acid, a molecule that plays a central role in protein synthesis.

Secretion

The process by which substances are produced and released from cells.

Sensor

A device or cell that detects and responds to stimuli.

Solubility

The ability of a substance to dissolve in another substance.

Solute

The substance that is dissolved in a solvent to create a solution.

Solvent

The substance in which a solute is dissolved, forming a solution.

Stimulus

An external factor that provokes a response in an organism.

Surface Area

The total area of the surface of a three-dimensional object.

Transport Vesicles

Membrane-bound vesicles that transport materials within a cell.

Vitamins

Organic compounds necessary for various metabolic processes in small amounts.

Stable disequilibrium

A condition where systems maintain a constant state despite external changes.

Form vs. Function

The principle that the form of a structure is closely related to its function.

“Unity in Diversity”

The concept that diverse organisms share fundamental biological principles.

Positive vs. Negative Feedback

Mechanisms of regulation where positive feedback amplifies a process, and negative feedback reduces output.

Stimulus vs. Response

The interaction where a stimulus evokes a response from an organism.

Functions of plasma membrane

The plasma membrane regulates what enters and exits the cell, protecting its integrity.

Protein Interactions

The various ways that proteins interact with each other to perform their functions.

Central Dogma

The framework explaining the flow of genetic information from DNA to RNA to protein.

Protein structure

The three-dimensional arrangement of atoms in a protein, critical for its function.

Nucleic acid Structure

The arrangement of nucleotides in DNA and RNA, determining genetic information.

Hydrophobic vs. Hydrophilic

Hydrophobic substances repel water, while hydrophilic substances readily interact with it.

Biological Solutions

Aqueous mixtures containing various solutes important for biological processes.

Bodily Compartments

Distinct sections of the body, such as cells and tissues, that maintain homeostasis.

Osmosis and Osmotic Pressure

The movement of water through a semipermeable membrane and the pressure required to stop it.

Exocytosis vs. Endocytosis vs. Phagocytosis

The processes of expelling materials from and internalizing substances into cells.