BIOL 102 Unit 3 Codon Vocab

respiration

The process of taking in O₂ and releasing CO₂. These gases are exchanged between cells and the environment via diffusion down their partial pressure gradients.

partial pressure

The pressure exerted by a specific gas in a mixture.

alveoli

Tiny sacs at the ends of branching tubes in the lungs that are covered with capillaries; are the site of gas exchange between air and cells in the body.

capillary

The smallest-diameter blood vessel in the body.

red blood cell

A cell in blood tissue that is specialized for carrying oxygen

heart

A muscular organ that pumps circulatory fluid (blood or hemolymph)

atrium

A structure in the heart that receives blood from the body

ventricle

A structure in the heart that pumps blood out to the body

artery

A vessel that carries blood away from the heart

capillary

An extremely small vessel where oxygen and other nutrients diffuse from the blood to tissues and where carbon dioxide and other wastes diffuse from tissues to the blood

vein

A vessel that carries blood toward the heart

stomach

A muscular, sac-like section of the digestive tract where a combination of extremely low pH and protease enzymes breaks large proteins into small chains of amino acids.

small intestine

An extremely long and coiled, tube-like section of the digestive tract whose interior lining has an extraordinarily large surface area. This is where digestion of lipids, proteins, carbohydrates, and nucleic acids is completed and fatty acids, amino acids, sugars, and nucleotides are absorbed into the body and transferred to the bloodstream.

large intestine

A large-diameter, tube-like section of the digestive tract where water is absorbed from food and feces are formed.

gall bladder

A bulb-shaped organ that stores bile salts produced in the liver and releases them into the start of the small intestine.

pancreas

An organ that synthesizes amylases, nucleases, proteases, and lipases and releases them, along with bicarbonate ions that neutralize protons, into the start of the small intestine.

parasite

An organism that takes resources from a host individual, reducing its fitness.

virion

An individual virus particle.

enveloped virus

A virus with a surface comprised of a lipid bilayer studded with viral proteins.

naked virus

A virus with surface comprised of a protein coat.

protease

An enzyme that catalyzes breaking peptide bonds in a long string of amino acids.

pathogen

Any virus, bacterium, or other entity that can cause disease.

parasite

Any organism that lives on or in a host, taking resources that increase its fitness and decrease the host's fitness.

innate immunity

Defenses against pathogens that are fully functional at birth and rely on proteins that recognize broad classes of invading cells and viruses.

acquired immune system

Defenses against pathogens that develop and change throughout an individual's life and rely on proteins that recognize and respond to specific antigens.

antigen

Any non-self molecule that elicits a response from the immune system. Usually a protein on the surface of an invading pathogen.

antibody

A protein produced by B cells that binds to a specific location on an antigen and marks it for other immune cells.

epitope

The specific location on an antigen where an antibody binds.

B Cells

Antibody-producing cells in the adaptive immune system.

T Cells

Cells in the adaptive immune system with receptors that bind to antigens presented on the surface of other cells.

Helper T Cells

T cells that assist with the activation of B cells and cytotoxic T cells. Also called CD4+ T cells.

Cytotoxic T Cells

T cells that bind to antigens displayed by infected self cells and respond by destroying those cells. Also called CD8+ T cells.

Memory Cells

Daughter cells of activated B cells and T cells that persist for years or decades after an infection. They can rapidly re-activate if the same infection occurs again.

Vaccination

Introduction of an antigen that does not cause disease but triggers a primary immune response and creation of memory cells.

epidermis

A tissue that forms the outer surface of structures in the plant root and shoot systems.

cuticle

A waxy layer on the external surface of epidermal cells in the shoot system.

guard cells

Kidney-shaped cells in the epidermis of the shoot system that form a pore that can open and close to regulate gas exchange.

turgor pressure

The force of a cell membrane pushing against a cell wall, created by a large amount of fluid inside the cell.

aquaporins

Membrane proteins that function as water channels.

Stomata

Regulated openings in leaves where gas exchange occurs

fitness trade-off

An unavoidable conflict between maximizing the fitness benefits and minimizing the fitness costs in aspects of one or more traits.

plasticity

The ability of the same genotype to produce different phenotypes in response to different environmental conditions.