Human Biology Theme 2

Study guide for exam 2

Debriefing

When an experiment involved deception, participants are told complete and truthful information about the experiment at its conclusion.

Deception

Purposely misleading experiment participants in order to maintain the integrity of the experiment

Informed Consent

Process of informing a research participant about what to expect during an experiment, any risks involved, and the implications of the research, and then obtaining the person’s consent to participate.

Institutional Animal Care & Use Committee (IACUC)

Committee of administrators, scientists, veterinarians, and community members that reviews proposals for research involving non-human animals.

Institutional Review Board (IRB)

Committee of administrators, scientists, and community members that reviews proposals for research involving human participants.

Alveolus

The terminal structure of the lung passage where gas exchange occurs.

Aorta

The major artery that takes blood away from the heart to the systemic circulatory system.

Artery

A blood vessel that takes blood away from the heart.

Atrium

A chamber of the heart that receives blood from the veins.

Bicuspid Valve

A one-way opening between the atrium and the ventricle in the left side of the heart.

Bronchi

Smaller branches of cartilaginous tissue that stem off of the trachea; air is funneled through the bronchi to the region where gas exchange occurs in the alveoli.

Bronchiole

An airway that extends from the main bronchus to the alveolar sac.

Capillary

The smallest blood vessel that allows the passage of individual blood cells and the site of diffusion of oxygen and nutrient exchange.

Cardiac Cycle

The filling and emptying the heart of blood caused by electrical signals that the site of diffusion of oxygen and nutrient exchange.

Closed Circulatory System

A system that has the blood separated from the bodily interstitial fluid and contained in blood vessels.

Diaphragm

A skeletal muscle located under lungs that encloses the lungs in the thorax.

Diastole

The relaxation phase of the cardiac cycle when the heart is relaxed and the ventricles are filling with blood.

Electrocardiogram (ECG)

A recording of the electrical impulses of the cardiac muscle.

Inferior Vena Cava

The major vein of the body returning from the lower parts of the body to the right atrium.

Larynx

The voice box, located within the throat.

Nasal Cavity

An opening of the respiratory system to the outside environment.

Open Circulatory System

A circulatory system that has the blood mixed with interstitial fluid in the body davity and directly bathes the organs.

Pharynx

The throat.

Primary Bronchus

A region of the airway within the lung that attaches to the trachea and bifurcates to form the bronchioles.

Pulmonary Circulation

The flow of the blood away from the heart through the lungs where oxygenation occurs and then back to the heart.

Superior Vena Cava

The major vein of the body returning blood from the upper part of the body to the right atrium.

Systemic Circulation

The flow of blood away from the heart to the brain, liver, kidneys, stomach, and other organs, the limbs, and the muscles of the body, and then back into the arteries.

Trachea

The cartilaginous tube that transports air from the throat to the lungs.

Tricuspid Valve

A one-way opening between the atrium and the ventricle in the right side of the heart.

Vein

A blood vessel that brings blood back to the heart.

Ventricle

A large chamber of the heart that pumps blood into arteries.

Plasma

Liquid component of blood that is left after the cells are removed.

Platelet

Small cellular fragment that collects at wounds, cross-reacts with clotting factors, and forms a plug to prevent blood loss.

Red Blood Cell

Small biconcave cell without mitochondria that is packed with hemoglobin, giving the cell its red color; transports oxygen through the body.

Serum

Plasma without the coagulation factors.

White Blood Cell

Large cell with nuclei of which there are many types with different roles including the protection of the body from viruses and bacteria and cleaning up dead cells and other waste.

COmplement System

An array of approximately 20 solube proteins of the innate iimmune system that enhance phagocytosis, bore holes in pathogens, and recruit lymphocytes.

Cytokine

A chemical messenger that regulates cell differentiation, proliferation, and gene expression to effect immune responses.

Inflammation

The localized redness, swelling, heat, and pain that results from the movement of leukocytes through opened capillaries to a site of infection.

Innate Immunity

An immunity that occurs naturally because of genetic factors or physiology, and it is not caused by infection or vaccination.

Interferon

A cytokine that inhibits viral replication.

Lymphocyte

A type of white blood cell that includes natural killer cells of the innate immune system and B and T cells of the adaptive immune system.

Macrophage

A large phagocytic cell that engulfs foreign particles and pathogens.

Mast Cell

A leukocyte that produces inflammatory molecules, such as histamine, in response to large pathogens.

Monocyte

A type of white blood cell that circulates in the blood and lymph and differentiates into a macrophage after it moves into infected tissue.

Natural Killer (NK) Cell

A lymphocyte that can kill cells infected with viruses or tumor cells.

Neutrophil

A phagocytic leukocyte that engulfs and digests pathogens.

Phagocytosis

The process by which a cell engulfs and digests a small object, such as a viral particle, bacterium or piece of cellular debris. Cells that can carry out phagocytosis are called phagocytes.

Pathogen

A microbe capable of causing disease.

Active Immunity

An immunity that occurs as a result of the activity of the body’s own cells rather than from antibodies acquired from an external source.

Adaptive Immunity

A specific immune response that occurs after exposure to an antigen either from a pathogen or a vaccination.

Antibody

A protein that is produced by plasma cells after stimulation by an antigen; also known as an immunoglobulin.

Antigen

A macromolecule that reacts with cells of the immune system and which may or may not have a stimulatory effect.

B Cell

A lymphocyte that matures in the bone marrow.

Cell-Mediated Immune Response

An adaptive immune response that is controlled by T cells.

Cytotoxic T Lymphocyte (Tc)

An adaptive immune cell that directly kills infected cells via enzymes, and that releases cytokines to enhance the immune response.

Effector Cell

A lymphocyte that has differentiated, such as a B cell, plasma cell, or cytotoxic T cell.

Helper T Lymphocyte (TH)

A cell of the adaptive immune system that binds APCs via MHC II Molecules and stimulates B cells or secretes cytokines to initiate the immune response.

Humoral Immune Response

The adaptive immune response that is controlled by activated B cells and antibodies.

Lymph

The watery fluid present in the lymphatic circulatory system that bathes tissues and organs with protective white blood cells and does not contain erythrocytes.

Memory Cells

An antigen-specific B or T lymphocyte that does not differentiate into an effector cell during the primary immune response but that can immediately become an effector cell on re-exposure to the same pathogen.

Passive Immunity

An immunity that does not result from the activity of the body’s own immune cells but by transfer of antibodies from one individual to another.

Primary Immune Response

The response of the adaptive immune system to the first exposure to an antigen.

Secondary Immune Response

The response of the adaptive immune system to a second or later exposure to an antigen medicated by memory cells.

T Cell

A lymphocyte that matures in the thymus gland.

Allele

Specific version of a gene.

Chromosome

Long strand of genetic information.

Deoxyribonucleic Acid (DNA)

Helix-shaped molecule made of nucleotide base pairs.

Dominant Allele

Allele whose phenotype will be expressed in an individual that possesses that allele.

Epigenetics

Study of gene-environment interactions, such as how the same genotype leads to different phenotypes.

Fraternal Twins

Twins who develop from two different eggs fertilized by different sperm, so their genetic material varies the same as in non-twin siblings.

Gene

Sequence of DNA that controls or partially controls physical characteristics.

Genetic Environmental Correlation

View of gene-environment interaction that asserts our genes affect our environment, and our environment influences the expression of our genes.

Genotype

Genetic makeup of an individual.

Heterozygous

Consisting of two different alleles.

Homozygous

Consisting of two identical alleles.

Identical Twins

Twins that develop from the same sperm and egg.

Mutation

Sudden, permanent change in a gene.

Phenotype

Individual’s inheritable physical characteristics.

Polygenic

Multiple genes affecting a given trait.

Range of Reaction

Asserts our genes set the boundaries within which we can operate, and our environment interacts with the genes to determine where in that range we will fall.

Recessive Allele

Allele whose phenotype will be expressed only if an individual is homozygous for that allele.

Theory of Evolution by Natural Selection

States that organisms that are better suited for their environments will survive and reproduce compared to those that are poorly suited for their environments.

mRNA

Messenger RNA; a form of RNA that carries the nucleotide sequence code for a protein sequence that is translated into a polypeptide sequence.

Nontemplate Strand

The strand of DNA that is not used to transcribe mRNA; this strand is identical to the mRNA except that T nucleotides in the DNA are replaced by U nucleotides in the mRNA.

Promoter

A sequence on DNA to which RNA polymerase and associated factors bind and initiate transcription.

RNA Polymerase

An enzyme that synthesizes an RNA strand from a DNA template strand.

Template Strand

The strand of DNA that specifies the complementary mRNA molecule.

Transcription Bubble

The region of locally unwound DNA that allows for transcription of mRNA.

Codon

Three consecutive nucleotides in mRNA that specify the addition of. a specific amino acid or the release of a polypeptide chain during translation.

Genetic Code

The amino acids that correspond to three-nucleotide codons of mRNA.

rRNA

Ribosomal RNA; molecules of RNA that combine to form part of the ribosome.

Stop Codon

One of the three mRNA codons that specifies termination of translation.

Start Codon

The AUG on an mRNA from which translation begins; always specifies methionine.

tRNA

Transfer RNA; an RNA molecule that contains a specific three-nucleotide anticodon sequence to pair with the mRNA codon and also binds to a specific amino acid.

Epigenetic

Describing non-genetic regulatory factors, such as changes in modifications to histone proteins and DNA that control accessibility to genes in chromosomes.

Gene Expression

Processes that control whether a gene is expressed.

Post-Transcriptional

Control of gene expression after the RNA molecule has been created but before it is translated into protein.

Post-Transitional

Control of gene expression after a protein has been created.