Chapter 8 Anatomy and Physiology Unit Summary - Vocabulary

Vocabulary flashcards covering key anatomy and physiology terms from Chapter 8 notes.

Homeostasis

The body's ability to maintain a stable internal environment despite external changes (e.g., temperature, pH, fluid balance).

Negative feedback

A regulatory mechanism that counteracts a stimulus to restore normal conditions and maintain homeostasis.

Feedback inhibition

A process in which a control system shuts down a response after achieving the desired effect to maintain balance.

Positive feedback

A regulatory mechanism that amplifies the initial stimulus rather than reversing it.

Pathophysiology

The study of how body functions change due to disease or disturbed homeostasis.

Absorption

The uptake of substances through membranes into cells or the body.

Circulation

The transport of substances throughout the body via body fluids.

Digestion

The breakdown of foods into simpler compounds that can be absorbed.

Excretion

The elimination of wastes from the body.

Growth

An increase in size or number of cells within an organism.

Movement

The ability to relocate or alter positions of body parts or internal structures.

Reproduction

The process of creating new cells or organisms.

Respiration (life function)

Using nutrients and oxygen to release energy and power cellular functions.

Responsiveness

The ability to respond to internal and external stimuli.

Levels of organization

A hierarchy in the body from chemical to organ system to organism.

Chemical level

Atoms and molecules that make up the body’s substances (water, sugars, proteins, lipids, nucleic acids).

Atom

The basic unit of matter; composed of protons, neutrons, and electrons.

Proton

Positively charged subatomic particle in the nucleus.

Neutron

Electrically neutral subatomic particle in the nucleus.

Electron

Negatively charged subatomic particle orbiting the nucleus.

Nucleus

Center of the atom containing protons and neutrons; in cells, the organelle housing DNA.

Electron cloud

Region around the nucleus where electrons are likely to be found.

Ionic bond

A bond formed by transfer of electrons between ions (cations and anions).

Covalent bond

A bond formed by sharing electrons between atoms.

Hydrogen bond

A weak bond between a hydrogen atom and a negatively charged atom; important in proteins and nucleic acids.

Polar molecule

A molecule with uneven distribution of charge, having a positive and a negative end (e.g., water).

Water (H2O)

A polar molecule; essential solvent and participant in many body reactions.

Carbohydrates

Molecules/compounds (sugars) that provide energy; include monosaccharides, disaccharides, and polysaccharides.

Monosaccharide

Simple sugar (e.g., glucose, fructose, galactose).

Disaccharide

Two monosaccharides linked together (e.g., sucrose, lactose, maltose).

Polysaccharide

Long chains of monosaccharides (e.g., starch, glycogen, cellulose).

Protein

Large organic molecules made of amino acids; perform structural, enzymatic, hormonal, and immune roles.

Amino acid

Building blocks of proteins; there are 21 different types; some are essential.��

Peptide bond

Bond linking amino acids in proteins.

Polypeptide

A long chain of amino acids; a protein when it has more than ~100 amino acids.

Enzyme

A biological catalyst that speeds up chemical reactions without being consumed.

Lipids

Hydrophobic organic molecules including triglycerides, phospholipids, and steroids (e.g., cholesterol) used for energy and membranes.

Triglycerides

Most common lipids; composed of glycerol and fatty acids; energy storage.

Cholesterol

Steroid lipid important for cell membranes and as hormone precursor.

Prostaglandins

Derivatives of essential fatty acids; regulate various cellular processes.

Fatty acids

Building blocks of lipids; essential fatty acids must be obtained from the diet.

Nucleic acids

DNA and RNA; macromolecules that store and transmit genetic information.

DNA

Genetic material of the cell; encodes information for protein synthesis.

RNA

Ribonucleic acid; involved in protein synthesis; three main types: mRNA, tRNA, rRNA.

Messenger RNA (mRNA)

Carries genetic code from DNA to ribosomes for protein synthesis.

Transfer RNA (tRNA)

Brings amino acids to the ribosome during protein synthesis.

Ribosomal RNA (rRNA)

Component of ribosomes; essential for protein synthesis.

Vitamins

Organic compounds required for normal metabolism; fat-soluble (A, D, E, K) and water-soluble (B complex, C).

Minerals

Inorganic elements essential for body function; macro- and micro/minerals.

Electrolytes

Ions released in water that conduct electricity; include cations and anions.

Cation

Positively charged ion (e.g., Na+, K+, Ca2+).

Anion

Negatively charged ion (e.g., Cl-, HCO3-).

Sodium

Principal extracellular cation; movement of Na+ influences water distribution.

Potassium

Principal intracellular cation; critical for neuromuscular function.

Calcium

Principle extracellular/cell function cation; important for bones, heart, clotting.

Magnesium

Cofactor in metabolism of proteins and carbohydrates.

Bicarbonate

Anion; important buffer in blood; helps maintain pH balance.

Chloride

Anion; contributes to pH balance in stomach and body fluids.

Phosphate

Anion; important component of ATP and cellular energy transfer.

Acids

Electrolytes that release hydrogen ions (H+) in solution.

Bases

Electrolytes that release ions that bond with hydrogen ions or accept H+.

pH

Measure of hydrogen ion concentration; 0-14 scale; 7 is neutral.

Acidosis

Blood pH below 7.35; can lead to severe physiological disruption.

Alkalosis

Blood pH above 7.45; can cause excessive nervous or muscular excitation.

Buffers

Molecules that moderate changes in pH; include proteins, phosphate, bicarbonate.

Cell

The basic functional unit of life; highly organized; capable of differentiation.

Differentiation

Process by which cells become specialized to perform specific functions.

Tissue

Group of similar cells performing related functions.

Organ

Structure made of two or more tissues working together to perform a specific function.

Cell membrane

Semipermeable boundary of the cell; controls movement of substances; contains proteins.

Nucleus

Cellular structure housing DNA and nucleolus; controls cell activities.

Cytoplasm

Fluid inside the cell surrounding organelles (cytosol) where many reactions occur.

Mitochondrion

Powerhouse of the cell; site of aerobic respiration and ATP production.

Ribosome

Organelle where protein synthesis occurs; can be free-floating or attached to ER.

Endoplasmic reticulum

Network of membranes; rough ER has ribosomes; smooth ER synthesizes lipids.

Golgi apparatus

Packages and modifies secretions and enzymes; renews cell membrane.

Lysosome

Organelle with enzymes that digest macromolecules and damaged organelles.

Peroxisome

Organelle containing enzymes that speed biochemical reactions; abundant in liver/kidney.

Cytoskeleton

Protein network (microfilaments, intermediate filaments, microtubules) giving cell shape and aids movement.

Centrioles

Cell structures that organize spindle fibers during cell division.

Mitochondrial cristae

Inner membrane folds of mitochondria where the electron transport chain takes place.

Nucleolus

Nuclear substructure where ribosome assembly begins.

Chromatin

DNA-protein complex that condenses to form chromosomes during division.

Meiosis

Cell division that reduces chromosome number in gametes (eggs/sperm).

Mitosis

Nuclear division producing two identical daughter cells; stages: prophase, metaphase, anaphase, telophase.

Cytokinesis

Division of the cytoplasm resulting in two separate cells.

Stem cells

Cells that can divide and differentiate into various cell types; essential for growth and repair.

Oncogenes

Mutated genes that contribute to cancer development.

Metastasis

Spread of cancer cells to distant sites to form secondary tumors.

Cell signaling

Communication between cells via chemical signals to coordinate function.

Cellular respiration

Process to extract energy (ATP) from glucose via glycolysis, Krebs cycle, and electron transport chain.

Glycolysis

First stage of cellular respiration; occurs in cytoplasm; glucose → pyruvate + ATP; can be anaerobic.

Krebs cycle

Aerobic stage in mitochondria producing CO2 and ATP; requires oxygen.

Electron transport system

Final stage in mitochondria producing most ATP via oxidative phosphorylation.

ATP

Adenosine triphosphate; main energy currency of the cell.

Total body water (TBW)

Approximately 60% of body weight in healthy adult males; divided into ICF and ECF.

Intracellular fluid (ICF)

Fluid inside cells; high in potassium, magnesium, and phosphate.

Extracellular fluid (ECF)

Fluid outside cells; high in sodium, chloride, bicarbonate; includes interstitial fluid, plasma, lymph.

Interstitial fluid

Fluid in the spaces between cells.

Plasma

Liquid portion of blood in the intravascular space.