BIo 1110 Comprehensive term list

Active Transport

Movement of molecules across a membrane from low to high concentration

ATP (Adenosine Triphosphate)

The main energy currency of the cell

Cell Membrane (Plasma Membrane)

A selectively permeable barrier composed of a phospholipid bilayer that controls the movement of substances into and out of the cell.

Chromosome

A structure made of DNA and protein that contains genetic information; replicates before cell division.

Diploid (2n)

A cell containing two copies of each chromosome (e.g.

Diffusion

The net movement of a population of molecules from an area of high concentration to an area of low concentration (down the concentration gradient).

Facilitated Diffusion

Movement of molecules down their concentration gradient across a membrane via transport proteins; does not require energy.

Fertilization

The fusion of haploid sperm and egg to form a diploid zygote.

Gamete

A haploid reproductive cell (sperm or egg).

Haploid (n)

A cell containing one copy of each chromosome (e.g.

Homologous Pair

The two copies of each chromosome in a diploid cell (one from each parent).

Hypertonic

A solution with a higher solute concentration compared to another solution; water moves out of a cell in this environment.

Hypotonic

A solution with a lower solute concentration compared to another solution; water moves into a cell in this environment.

Isotonic

Two solutions with the same solute concentration; no net movement of water.

Meiosis

Cell division that produces four genetically unique haploid daughter cells (gametes) from a diploid parent cell.

Mitosis

Cell division that produces two genetically identical diploid daughter cells for growth

Osmosis

The diffusion of water across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration.

Passive Transport

Movement of molecules down their concentration gradient without the use of energy (includes diffusion

Selectively Permeable

A property of the cell membrane that allows some molecules to pass through but not others.

Somatic Cell

Any cell in an animal's body that is not a gamete (diploid).

Transport Protein

A protein embedded in the cell membrane that helps move specific molecules across (facilitated diffusion or active transport).

Zygote

The diploid cell resulting from the fusion of two gametes.

Alveoli

Tiny

Bronchi/Bronchioles

Branching air passages in the lungs that lead from the trachea to the alveoli.

Countercurrent Flow

The flow of water and blood in opposite directions across fish gills

Gills

Gas exchange organs in aquatic animals

Lungs

Internal gas exchange organs in terrestrial vertebrates

Negative Pressure Breathing

Ventilation mechanism (e.g.

Parabronchi

Small

Positive Pressure Breathing

Ventilation mechanism (e.g.

Spiracles

Small pores on the body of insects through which air enters the tracheal system.

Tracheal System

A network of air-filled tubes (tracheae and tracheoles) in insects that delivers oxygen directly to cells.

Ventilation

The flow of a respiratory medium (air or water) across a respiratory surface.

Arteries

Thick-walled blood vessels that carry blood away from the heart.

Atrium (pl. Atria)

Heart chamber that receives blood from veins and pumps it to the ventricle.

Capillaries

Microscopic

Closed Circulatory System

A system where blood is contained within vessels and is separate from the interstitial fluid (e.g.

Double Circulation

A circulatory system with two separate circuits (pulmonary to lungs

Hemolymph

The circulatory fluid in open circulatory systems.

Interstitial Fluid

The fluid that fills the space between body cells; the medium for exchange between blood and cells.

Open Circulatory System

A system where hemolymph is pumped through open-ended vessels into a body cavity (hemocoel) and directly bathes organs.

Single Circulation

A circulatory system with one circuit where blood passes through the heart once per complete cycle (e.g.

Veins

Thin-walled blood vessels that carry blood toward the heart.

Ventricle

A heart chamber that pumps blood into arteries.

Ammonia (NH3)

A highly toxic nitrogenous waste

Collecting Duct

The final segment of the nephron where water is reabsorbed

Cortical Nephron

Nephron with a short loop of Henle that does not extend deep into the medulla.

Excretion

The process of removing metabolic wastes (especially nitrogenous wastes) from the body.

Juxtamedullary Nephron

Nephron with a long loop of Henle that extends deep into the medulla; allows production of concentrated urine.

Kidney

The vertebrate organ responsible for excretion

Loop of Henle

The U-shaped portion of a nephron responsible for creating a concentration gradient in the medulla.

Metanephridia

Excretory structures in annelids (e.g.

Malpighian Tubules

Excretory structures in insects that remove wastes from hemolymph and empty into the digestive tract.

Nephron

The functional unit of the vertebrate kidney.

Nitrogenous Waste

Waste products (ammonia

Osmoregulation

The active regulation of an organism's internal solute and water balance.

Osmoregulator

An animal that maintains a constant internal osmolarity different from its environment

Osmoconformer

An animal whose internal osmolarity matches its environment (typically marine invertebrates); does not expend energy on osmoregulation.

Protonephridia

Excretory structures in flatworms that filter interstitial fluid.

Transport Epithelium

Specialized tissue lining excretory tubules that moves solutes and water.

Urea

A moderately toxic nitrogenous waste

Uric Acid

A non-toxic

Asexual Reproduction

Production of offspring from a single parent without gamete fusion (e.g.

Budding

A form of asexual reproduction where a new individual grows as an outgrowth (bud) from the parent.

External Fertilization

Fusion of gametes outside the parent's body

Fragmentation

A form of asexual reproduction where the parent breaks into pieces

Gonochoristic

A species with separate male and female individuals.

Hermaphroditic

An individual that has both male and female reproductive organs.

Internal Fertilization

Fusion of gametes inside the female's body.

Oviduct (Fallopian Tube)

Tube that transports an egg from the ovary to the uterus.

Oviparous

Development where offspring grow inside eggs laid outside the mother's body; nourished by yolk.

Ovoviviparous

Development where eggs are retained inside the mother's body but the embryo is nourished by yolk; results in live birth.

Ovary

Female gonad that produces eggs (ova).

Parthenogenesis

Asexual reproduction where an unfertilized egg develops into a new individual.

Penis

Male copulatory organ used for internal fertilization.

Sexual Reproduction

Production of a new

Testis

Male gonad that produces sperm.

Uterus

Organ in female mammals where the embryo/fetus develops during viviparous pregnancy.

Vagina

Birth canal and copulatory organ in female mammals.

Vas Deferens

Tube that carries sperm from the testis to the ejaculatory duct.

Viviparous

Development where the embryo develops inside the mother's uterus and is nourished directly by the mother (e.g.

Adhesion

Attraction between water molecules and different molecules (e.g.

Capillary Action

The tendency of water to climb up a narrow tube due to cohesion

Cellular Respiration (in plants)

Process using O2 and sugars to produce ATP

Cohesion

Attraction between water molecules.

Cytoplasmic Streaming

Circulation of cytoplasm within and between plant cells (via plasmodesmata) to move organelles and molecules.

Guard Cells

Two specialized cells flanking a stoma that control its opening by changing shape (turgor pressure).

Lenticel

A pore in the bark of woody stems and roots that allows for gas exchange; does not open/close like stomata.

Phloem

Vascular tissue that transports sugars (organic nutrients) from source to sink.

Photosynthesis

Process using CO2

Pressure-Flow Model

Mechanism explaining phloem transport; sugar loading at source creates high pressure

Root Hair

Epidermal cell extension on growing root tips that increases surface area for gas exchange and water/nutrient absorption.

Root Pressure

Positive pressure in xylem generated at night by active transport of minerals into roots

Source (Sugar Source)

A plant organ that produces or releases sugar (e.g.

Sink (Sugar Sink)

A plant organ that consumes or stores sugar (e.g.

Stoma (pl. Stomata)

Pore in leaf surface

Transpiration

Evaporation of water from plant leaves

Transpiration-Cohesion-Tension Mechanism

The process by which water is pulled up from roots to leaves: transpiration creates tension

Xylem

Vascular tissue that transports water and minerals from roots to shoots.

Alternation of Generations

A plant life cycle that alternates between a multicellular diploid sporophyte and a multicellular haploid gametophyte generation.