BIOL 1150-51 Exam 2 Study Guide Flashcards

Atom

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

Atomic Number

The number of protons in the nucleus of an atom, which determines the chemical properties of an element and its place in the periodic table.

Atomic Weight

The average mass of atoms of an element, calculated using the relative abundance of isotopes in a naturally occurring element.

Hydrogen Bond

A weak bond between two molecules resulting from an electrostatic attraction between a proton in one molecule and an electronegative atom in the other.

Ionic Bond

A chemical bond resulting from the electrostatic attraction between oppositely charged ions.

Covalent Bond

A chemical bond by mutual sharing of pairs of electrons between 2 atoms

Polar Covalent Bond

A type of chemical bond where a pair of electrons is unequally shared between two atoms.

pH

A measure of how acidic/basic water is. The range goes from 0 - 14, with 7 being neutral. pHs of less than 7 indicate acidity, whereas a pH of greater than 7 indicates a base.

Condensation Reaction

A chemical reaction in which two molecules or moieties (functional groups) combine to form a larger molecule, together with the loss of a small molecule.

Hydrolysis Reaction

break down by consuming water molecule

Lipids

Naturally occurring molecules including fats, waxes, and vitamins that store energy, signal, and support cell membrane structure.

Carbohydrates

Any of a large group of organic compounds occurring in foods and living tissues and including sugars, starch, and cellulose. They typically contain hydrogen and oxygen in the same ratio as water (2:1) and can be broken down to release energy in the animal body.

Nucleic Acids

A complex organic substance present in living cells, especially DNA or RNA, whose molecules consist of many nucleotides linked in a long chain.

Proteins

Large biomolecules and macromolecules that comprise one or more long chains of amino acid residues.

Triglyceride

An ester formed from glycerol and three fatty acid groups. Triglycerides are the main constituents of natural fats and oils, and high concentrations in the blood indicate an elevated risk of stroke.

Saturated Fatty Acid

A fatty acid in which all carbons in the hydrocarbon tail are connected by single bonds, thus maximizing the number of hydrogen atoms that can attach to the carbon skeleton.

Unsaturated Fatty Acid

A fatty acid possessing one or more double bonds between the carbons in the hydrocarbon tail. Such bonding reduces the number of hydrogen atoms that can attach to the carbon skeleton.

Homeostasis

The ability to maintain a stable internal environment despite changes in external conditions.

Cell Theory

A widely accepted explanation of the relationship between cells and living things

Cell

The structural and functional unit of all living organisms.

Prokaryotic Cell

A cell lacking a nucleus and other membrane-bound organelles.

Eukaryotic Cell

A cell with a nucleus and other membrane-bound organelles.

Phospholipid

A lipid containing a phosphate group in its molecule.

Hydrophilic

Having a tendency to mix with, dissolve in, or be wetted by water.

Hydrophobic

Tending to repel or fail to mix with water.

Diffusion

The process of a substance spreading out to fill a space

Facilitated Diffusion

The process of spontaneous passive transport (as opposed to active transport) of molecules or ions across a biological membrane via specific transmembrane integral proteins.

Active Transport

The movement of ions or molecules across a cell membrane into a region of higher concentration, assisted by enzymes and requiring energy.

Osmosis

A process by which molecules of a solvent tend to pass through a semipermeable membrane from a less concentrated solution into a more concentrated one, thus equalizing the concentrations on each side of the membrane.

Hypertonic Solution

A solution with a higher solute concentration compared to another solution.

Hypotonic Solution

A solution with a lower solute concentration compared to another solution.

Isotonic Solution

A solution with the same solute concentration as another solution.

Organelles

Any of a number of organized or specialized structures within a living cell.

Nucleus

The central and most important part of an object or group, forming the basis for its activity and growth.

Ribosomes

A minute particle consisting of RNA and associated proteins, found in large numbers in the cytoplasm of living cells. They bind messenger RNA and transfer RNA to synthesize polypeptides and proteins.

Rough ER

The region of the endoplasmic reticulum that is studded with ribosomes and engages in protein modification and transport.

Smooth ER

The region of the endoplasmic reticulum that has few or no ribosomes on its cytoplasmic surfaces and synthesizes carbohydrates, lipids, and steroid hormones; detoxifies certain chemicals; and stores calcium ions.

Golgi Apparatus

A eukaryotic organelle consisting of a stack of flattened membranous sacs that modify, store, and route products of the endoplasmic reticulum and synthesize some products, notably noncellulose carbohydrates.

Lysosomes

A membrane-bound cell organelle that contains digestive enzymes.

Mitochondria

The powerhouse of the cell and generates most of the chemical energy needed to power the cell's biochemical reactions.

Cytoskeleton

A network of protein filaments within some cells that helps the cell maintain its shape and is involved in many forms of cell movement.

ATP

The main energy source that cells use for most of their functions.

Cellular Respiration

The set of metabolic reactions and processes that take place in the cells of organisms to convert chemical energy from oxygen molecules or nutrients into adenosine triphosphate (ATP), and then release waste products.

Aerobic

Requiring air or oxygen for life or survival which get far more ATP from each glucose molecule than anaerobic respiration

Anaerobic

Not requiring air or oxygen for life or survival.

Fermentation

A metabolic process that produces chemical changes in organic substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in the absence of oxygen.

Nervous System

The network of nerve cells and fibers which transmits nerve impulses between parts of the body.

Central Nervous System

The complex of nerve tissues that controls the activities of the body. In vertebrates it comprises the brain and spinal cord.

Peripheral Nervous System

The nervous system outside the brain and spinal cord.

Sensory

Relating to sensation or the physical senses; transmitted or perceived by the senses.

Motor

Relating to movement.

Neuron

A specialized cell transmitting nerve impulses; a nerve cell.

Neuroglial Cells

Also called glial cells or glia, are non-neuronal cells in the central nervous system (brain and spinal cord) and the peripheral nervous system that do not produce electrical impulses. They maintain homeostasis, form myelin, and provide support and protection for neurons.

Myelination

The process of forming a myelin sheath around a nerve to allow nerve impulses to move more quickly.

Saltatory Conduction

The propagation of action potentials along myelinated axons from one node of Ranvier to the next node, increasing the conduction velocity of action potentials.

Ion Channels

Pores or openings in a cell membrane that allow for the passage of specific ions.

Na-K Pump

A protein found in the plasma membrane of all animal cells that expels sodium ions (Na+) from the cell and brings potassium ions (K+) into the cell.

Local Potential (Graded Potential)

Changes in the membrane potential of a neuron that cannot spread far from the site of stimulation.

Action Potential

The change in electrical potential associated with the passage of an impulse along the membrane of a muscle cell or nerve cell.

Axolemma

The cell membrane of an axon.

Resting Membrane Potential

The voltage (charge) difference across the cell membrane when the cell is at rest.

Threshold

The level of stimulation required to trigger a neural impulse.

Depolarization

When the membrane potential becomes less negative.

Repolarization

When the membrane potential returns to its resting value.

Hyperpolarization

When the membrane potential becomes more negative than its resting value.

All-or-None Principle

States that the strength of a response of a nerve cell or muscle fiber is not dependent upon the strength of the stimulus. If a stimulus is above a certain threshold, a nerve or muscle fiber will fire. Essentially, there will either be a full response or there will be no response at all.

Refract