A&P Exam 1

11 organ system

The number of organ systems in the human body

Homeostasis

Maintenance of a stable internal environment

Autoregulation

Automatic adjustment of blood flow to a particular area

Receptor

Specialized cell or structure that detects changes in the environment

Control Center

Determines the set point at which a variable is maintained

Effector

Cell or organ that carries out the final corrective action

Positive Feedback

Process that reinforces a change in the body's conditions

Negative Feedback

Process that reverses a change in the body's conditions

Serous Membrane

Thin double-layered membrane that covers organs in body cavities

Matter

Anything that occupies space and has mass

Energy

The capacity to do work or put matter into motion

Kinetic

Energy of motion

Potential

Stored energy

Mechanical energy

Energy directly involved in moving matter

Chemical energy

Energy stored in chemical bonds

Electrical energy

Energy resulting from the movement of charged particles

Radiant energy

Energy that travels in waves

Protons

Positively charged particles in the nucleus of an atom

Neutrons

Particles in the nucleus of an atom with no charge

Electrons

Negatively charged particles that orbit the nucleus of an atom

Atomic Number

Number of protons in an atom

Atomic Mass

Total mass of an atom

Isotopes

Atoms of the same element with different numbers of neutrons

Radioactive Isotopes

Unstable isotopes that emit radiation

Neutral atoms

Atoms with equal numbers of protons and electrons

Ions

Charged atoms that have gained or lost electrons

Cations

Positively charged ions

Anions

Negatively charged ions

Ionic bonds

Bonds formed between oppositely charged ions

Valence Electrons

Electrons in the outermost energy level of an atom

Molecules

Two or more atoms held together by chemical bonds

Compounds

Molecules composed of two or more different elements

Covalent Bonds

Bonds formed by sharing electrons

Polar

Molecule with a slightly positive and slightly negative end

Nonpolar

Molecule with an equal distribution of charge

Electronegativity

Ability of an atom to attract electrons

Elements in the body

O, C, H, N

Hydrogen Bond

Weak attraction between a hydrogen atom and an electronegative atom

Chemical Reaction

Process that changes one set of chemicals into another

Metabolism

All chemical reactions that occur in the body

Decomposition

Breaking down complex molecules into simpler ones

Hydrolysis

Breaking down a compound by adding water

Catabolism

Metabolic pathways that break down molecules

Synthesis

Combining of small molecules to form larger ones

Dehydration

Removing water to join monomers together

Anabolism

Metabolic pathways that build molecules

Exchange

Process of moving substances into, out of, or between cells

Oxidation-reduction

Chemical reactions that involve the transfer of electrons

Acid

A substance that donates hydrogen ions

Base

A substance that accepts hydrogen ions

Buffer

A solution that resists changes in pH

Organic Molecule

Molecule that contains carbon

Polymer

Large molecule made up of repeating subunits

Biological Macromolecules

Large molecules necessary for life

1:2:1 ratio

Ratio of carbon, hydrogen, and oxygen in carbohydrates

Monosaccharides

Simple sugars in energy storage

6 Carbon

Glucose

Glucose

A monosaccharide and the primary source of energy for cells

Disaccharides

Double sugars composed of two monosaccharides

Polysaccharide

Complex carbohydrates made up of many monosaccharides

Cellulose

Polysaccharide that provides structural support in plant cell walls

Starch

Polysaccharide that serves as a storage form of glucose in plants

Glycogen

Polysaccharide that serves as a storage form of glucose in animals

Lipid

Molecule that is insoluble in water

Triglyceride

Lipid composed of three fatty acids and a glycerol

Phospholipid

Structural lipid that are mainly synthesized from fatty acids

Glycerol

Three-carbon molecule that forms the backbone of triglycerides

Cholesterol

Steroid that is an important component of cell membranes

Steroids

cortisol, testosterone, and estradiol

Proteins

Polymers made up of amino acid subunits

Peptide Bond

Covalent bond between two amino acids

Polypeptide

Chain of amino acids

Primary Structure

Sequence of amino acids in a protein

Secondary Structure

Gives the protein a 3D structure

Tertiary Structure

Most functional in this stage, determines how the protein is further arranged

Quaternary Structure

Association of multiple polypeptide chains that form a functional protein

Denatured

Loss of a protein's shape and function due to heat or pH

Enzyme

Promotes chemical reaction by lowering activation energy but are not altered during reaction

Activation Energy

Extra energy required to start a chemical reaction

Catalyst

Substance that speeds up the rate of a chemical reaction

Substrate

a molecule that will undergo a reaction

Active Site

Region of an enzyme where the substrate binds

Nucleic Acids

carry information

DNA

Double-stranded nucleic acid that contains genetic information - Deoxyribonucleic Acid

RNA

Single-stranded nucleic acid involved in protein synthesis - Ribonucleic Acid

Nucleotides

Building blocks of nucleic acids made of subunits

Nitrogenous Bases

Adenine, Thymine, Cytosine, Guanine, Uracil

Phosphodiester Bond

Covalent bdond between nucleotides in a nucleic acid

Compliment Pairs

Adenine pairs with Thymine, Cytosine pairs with Guanine

Sugar Phosphate

Backbone of a nucleic acid

Double Helix

Structure of DNA

ATP

Adenosine triphosphate, the energy currency of the cell

Ribose

Five-carbon sugar in RNA

Mitochondria

Organelles that produce ATP; powerhouse of the cell

Ribosomes

Organelles that synthesize proteins

Rough Endoplasmic Reticulum

Organelle involved in protein synthesis

Smooth Endoplasmic Reticulum

Organelle involved in lipid synthesis

Golgi Apparatus

Organelle that modifies, sorts, and packages proteins

Lysosomes

Organelles that contain intracellular digestive enzymes

Microfilaments

move the cell