E Flashcards
EC Coupling
Excitation contraction coupling refers to the steps between depolarization of the muscle cell membrane (excitation) and the activation of that muscle (contraction).
Eccrine Gland
A type of exocrine gland characterized by a long coiled duct that delivers secretions from the secretory region to the surface.
Ecdysis
The periodic shedding of the exoskeleton of invertebrates (molting).
Ecdysone
One of the ecdysteroid hormones of arthropods that is responsible for controlling
many aspects of development, including ecdysis.
Ecdysteroids
The general name for ecdysone and its active metabolites, such as 20-hydroecdysone.
Echolocation
Dectecting objects based on the reflection of sound waves; used by organisms such as whales and bats.
Eclosion
The process whereby an adult insect emerges from its cocoon.
Ectoderm
The outermost of the primary germ layers in a developing embryo that eventually gives rise to tissue such as the nervous system.
Ectopic Pacemaker
A pacemaker in an abnormal location.
Ectotherm
see also endotherm
An animal with body temperature determined primarily by external factors, including but not limited to ambient temperature.
Edema
Excess accumulation of fluid in a tissue.
Effective Refractory Period
The time period in which an excitable tissue cannot be stimulated due to changes in the membrane potential.
Effector
An organ or cell such as a muscle that responds to stimulation from the nervous system.
Efferent
Leading away from a structure;
e.g.,
efferent neurons carry signals from the central nervous system to the periphery;
efferent arterioles carry blood away from the glomerulus of the kidney.
Efferent Arteriole
The arteriole that emerges from the glomerulus of the kidney tubule.
Efferent Division
The part of the peripheral nervous system that consists of efferent neurons.
Efferent Neuron
A neuron that conducts impulses from an integrating center to an effector.
Efflux
Movement of a substance outward, usually in the context of movement out of a cell or tissue.
Egestion
Expulsion of undigested food (feces) from the digestive tract.
Eicosanoids
A type of short-lived chemical signaling molecule.
Elasmobranch Fish
One of two groups of cartilaginous fish, including skates, rays, and sharks. The other group of cartilaginous fish is holocephalans (ratfish).
Elastance
A measure of how readily a structure returns to its original shape after having been stretched.
Elastic Recoil
Movement as a result of the release of elastic storage energy
Elastic Storage Energy
Energy stored within a deformed object, which is released when the object regains its relaxed configuration.
Electrical Gradient
A charge gradient across a membrane arising from unequal distribution of charged particles.
Electric Organ
A trans-differentiated muscle of fish that generates electric pulses for detecting objects or defense.
Electrical Energy
The energy associated with gradients of charged particles.
Electrical Synapse
see also chemical synapse
A junction between neurons in which the signal is transmitted as an electrical charge rather than via a neurotransmitter.
Electrocardiogram (ECG, EKG)
A recording of the electrical activity of the heart.
Electrocardiograph
see electrocardiogram
An instrument that measures electrical potentials on the body surface as an indication of the electrical activity of the heart
Electrochemical Gradient
A gradient composed of the concentration gradient of an ion and the membrane potential; the driving force for the movement of that ion across the membrane.
Electrochemical Potential Difference (Δμ)
see electrochemical gradient
The driving force for movement of a substance across a membrane as a result of the electrical and chemical gradients across the membrane.
Electrogenic
A transport process that results in a change in electrical charge across a membrane.
Electrolyte
A charged solute, such as Na+, K+, and Cl−.
Electron Transport System (ETS)
A series of protein complexes with mobile carriers that produce a proton gradient across the inner mitochondrial membrane. It builds the gradient by pumping protons as it transfers electrons from reducing equivalents to oxygen,
forming water.
Electroneutral
A transport process that does not change the electrical charge across a membrane.
Electroreceptor
A sensory receptor that responds to electric fields or discharges.
Electrotonic Current Spread
The passive conduction of charge along a cell membrane.
Elevated Postexercise Oxygen Consumption (EPOC)
A period of elevated metabolic rate thought to be necessary to allow the muscle
to recover from ionic and metabolic disturbances that arose as a result of intense exercise.
Emergence
A phenomenon in which the patterns and properties of a complex system are
the result of the interactions of the component parts of that system, and are not necessarily predictable from the operation of those components in isolation.
Emergent Properties
Traits of an organism that are the result of the phenomenon of emergence across levels of organization.
Empirical
An observation arising from direct measurement of a parameter.
Encephalization Quotient (EQ)
The ratio of actual brain size to predicted brain size based on body size; suggested as a way to compare intelligence between species.
End-Diastolic Volume (EDV)
The volume of blood in the heart at the end of diastole; the maximum volume reached during the cardiac cycle.
End-Systolic Volume (ESV)
The volume of blood in the heart at the end of systole; the minimum volume reached during the cardiac cycle.
Endergonic Reaction
A reaction that requires an input of free energy, for which G is positive.
Endocardium
The internal layer of the heart.
Endocrine
A signaling pathway in which the signaling molecule is released into the blood
and affects a distant cell of a different type.
Endocrine Disruptor
An environmental chemical (often humanmade) that alters cell signaling
by acting as an analogue or antagonist of an endocrine hormone.
Endocrine Gland
Type of gland that secretes hormones into the blood.
Endocrine System
The collective name for the group of glands and other tissues that secrete hormones into the circulatory system.
Endocytosis
Invagination of the plasma membrane resulting in the formation of a vesicle;
used to internalize membrane proteins or capture extracellular solids (phagocytosis) or liquids (pinocytosis).
Endoderm
The innermost primary germ layer in a developing embryo; eventually gives rise
to tissues such as the external surfaces, including the gut lining.
Endolymph
The fluid in the inner ear of vertebrates.
Endometrium
see also myometrium
The innermost layer of the uterus composed of well-vascularized epithelial
tissue.
Endoplasmic Reticulum (ER)
An intracellular organelle that forms a network through which secretory products and plasma membrane components pass.
Endoskeleton
More commonly referred to as the skeleton, an internal framework of bones,
cartilage, and tendons that provides support and resistance for muscular movement.
Endosymbiont
An organism that lives within another organism.
Endosymbiosis
A relationship whereby an organism lives within another cell or organism, and both parties benefit from the relationship.
Endothelium
The innermost layer of blood vessels.
Endotherm
An animal that generates and retains heat internally.
Endothermic Reaction
A reaction that has a positive H, requiring heat.
End-Systolic Volume (ESV)
The volume of blood in the heart at the end of systole; the minimum volume of blood that the heart contains during the cardiac cycle.
Energetics
The study of processes that involve the interconversion of energy.
Energy
The ability to do work.
Energy Metabolism
The sum of metabolic reactions that pertain to the production or utilization
of energy.
Enteric Branch
also enteric division; enteric nervous system
Part of the vertebrate autonomic nervous system involved in regulating
the activity of the gut.
Enterosymbiont
A symbiotic organism that lives within the gastrointestinal tract.
Enthalpy
The heat content of a system, symbolized as H. Chemical reactions are often
expressed as a change in enthalpy (H).
Entropy
A thermodynamic parameter that reflects the degree of disorder in a system.
Environmental Estrogen
An estrogenlike endocrine disruptor.
Enzyme
A biological catalyst composed of protein (sometimes RNA), frequently incorporating a cofactor into its structure.
Enzyme Induction
An increase in the levels of an enzyme: one way to achieve an increase in
catalytic activity.
Enzyme Kinetics
The collection of parameters that describe functional properties of enzymes,
including maximal velocity (V_max) and affinity (K_m).
Eosinophil
A type of white blood cell that is involved in the immune response to parasites
an in allergic reactions
Ependymal Cells
Cells that line the ventricles of the brain.
Epicardium
The outer layer of the heart in vertebrates.
Epididymis
The structure where sperm mature and are stored in the vertebrate testis.
Epigenetic Inheritance
Modifications of DNA without a change in the DNA sequence that can be transmitted from parent to offspring.
Epinephrine
A catecholamine that can act as a hormone or neurotransmitter and is involved
in the stress response; also called adrenaline.
Epithalamus
A region of the vertebrate brain that contains the pineal body.
Epithelium
The outermost cellular layer of eumetazoans.
Equilibrium
For a chemical reaction, the state in which there is no net change in the reactants; products and substrates continue to interconvert, but at equal rates.
Equilibrium Constant (K_eq)
The mass action ratio of a chemical reaction when the reaction is at equilibrium.
Equilibrium Potential
The membrane potential at which an ion is at its equilibrium distribution across a membrane.
Eructation
Gaseous release from the stomach (belching).
Erythrocyte
A type of vertebrate blood cell that contains hemoglobin (red blood cell).
Erythropoiesis
Production of red blood cells from erythroblasts, usually in specialized erythropoietic tissues.
Erythropoietin
A hormone released from the kidney that induces erythropoiesis.
Esophagus
The passage from the oral cavity (mouth) to the stomach.
Essential Nutrient
A nutrient that cannot be made by the animal and therefore must be obtained from the diet.
Esterase
An enzyme that breaks an ester bond.
Estivation
A form of dormancy in which the reduced metabolic rate occurs in response to
dehydration.
Estradiol-17β
The dominant estrogen in most species.
Estrogens
A class of steroid hormones that act predominantly in females to stimulate reproductive maturation and control the reproductive cycle.
Estrous Cycle
A reproductive cycle composed of four phases: proestrus, estrus, metestrus, and diestrus.
Ethology
The study of animal behavior.
Eumetazoans
Animals, excluding sponges and placozoans.
Eupnea
Normal breathing.
Euryhaline
Tolerant of a wide range of external salinities, or more precisely osmolarities.
Eurytherm
An animal that is tolerant of a wide range of external temperatures.
Evaporation
Volatilization of liquid water to gaseous water, with the absorption of heat.
Evaporative Cooling
The heat loss that results when heat is absorbed from the body to enable surface water to evaporate.
Evolution
The process of descent with modification, or genetic change in taxa over time; may be adaptive, maladaptive, or neutral.
Excitable Cell
A cell that is capable of producing an action potential.
Excitation-Contraction Coupling
or EC coupling
The processes that link external stimulation of a muscle to the activation of actinomyosin ATPase, resulting in muscle contraction.
Excitatory Postsynaptic Potential (EPSP)
An excitatory potential in a postsynaptic cell.
Excitatory Potential
A change in the membrane potential in an excitable cell that increases the probability of action potential initiation in that cell.
Exergonic Reaction
A reaction that requires an input of free energy, for which G is positive.
Exocrine Gland
A type of gland that releases its secretions via a duct (usually into the external
environment).
Exocrine Secretions
Secretions from exocrine glands; include chemical messengers and substances such as mucus, slime, and silk.
Exocytosis
The transport of vesicles to, and subsequent fusion with, the plasma membrane;
serves to secrete vesicle contents into the extracellular space or to introduce proteins into the plasma membrane.
Exon
A region of DNA that codes for a protein.
Exoskeleton
An external rigid structure on the outside of many invertebrates that serves
to restrict the movement of water and provide a solid framework that controls animal shape and provides resistance needed for locomotion.
Exosymbiont
A symbiotic organism that lives outside the animal.
Exothermic Reaction
A reaction that has a negative H value, releasing heat.
Expiration
Exhalation.
Extension
A movement that causes a limb to straighten across a joint, usually caused by
contraction of an extensor muscle.
Extensor
A muscle that causes a limb to straighten across a joint (extension).
External Respiration
see also respiration
The process by which animals exchange gases with the environment to supply oxygen to the mitochondria and to remove the resulting carbon dioxide.
Extracellular Digestion
Breakdown of nutrients in the outside of the cell resulting from secretion of digestive enzymes.
Extracellular Fluids
The fluids outside of a cell but contained within the limits of the organism.
Extracellular Matrix
The protein and glycosaminoglycan network found outside cells; includes cartilage, bone, and connective tissue.
Extrarenal
Occurring in a tissue other than the kidney.
Extremophiles
Organisms that tolerate environmental extremes, such as temperature, salinity, and pressure.
Eye
A complex organ that detects light.
