41 terms

Biology Chapter 3 Vocab

Cell interior that is surrounded by a wall made of carbohydrates and proteins and a membrane that is made largely of phospholipids
Transport Proteins
Special proteins that are embedded in the cell membrane
Selectively Permeable
Membranes that regulate the exchange of materials in a very specific way
Proteins that are embedded in membranes that have sugars attached to them
Sugars that are attached to the heads of membrane lipids
The movement of molecules from an area of higher concentration to an area of lower concentration
Concentration Gradient
Is existent when there is a difference in concentration of molecules across a distance
A special form of diffusion; the movement of water across a selectively permeable membrane
The outward pressure of a cell against its cell wall
Passive Transport
Involves diffusion without any input of energy
Active Transport
Moves substances against their concentration gradients and thus requires energy
Facilitated Diffusion
The transport in which molecules move down their concentration gradient with the help of transport proteins in the membrane
The process by which very large molecules are moved into a cell by a special active transport mechanism that requires energy
The process by which very large molecules are moved out of a cell by a special active transport mechanism that requires energy
Air sacs in a lung
The waxy outer layer covering the surfaces of most land-dwelling plants, animals, and fungi
The opening between two guard cells in the epidermis of a plant leaf through which gases are exchanged with the air
The loss of water to the atmosphere by a plant through the stomates in its leaves
The tendency for an organism to maintain a relatively stable internal environment by regulating its metabolism and adjusting to its environment
A toxic nitrogen compound (NH3) excrete by some aquatic organisms; thought to have been present in Earth's early atmosphere
The functional unit of a kidney consisting of a glomerulus, its associated capsule, and tubule surrounded by capillaries
An organ that regulates water and salt levels, filters water and wastes from the blood, and excretes the end products
Urinary System
A vertebrate organ system that regulates levels of water and dissolved substances in the body, excreting wastes as urine
The solution of wastes excreted from the kidney
A muscular tube that carries urine from the kidney to the urinary bladder
Urinary Bladder
An organ that stores urine before it is discharges from the body through the urethra
The tube through which urine travels from the bladder to the outside of the body
Glomerular Capsule
The cup of a nephron, which filters blood; also called Bowman's capsule
A ball of capillaries surrounded by a glomerular capsule in the nephron; the site of filtration in the kidneys
A hormone secreted by the adrenal gland, helps regulate sodium and potassium concentrations and water balance
Feedback Regulation
The regulation of the activity of an enzyme by one of its products
A hormone released from the posterior lobe of the pituitary (an endocrine gland in the brain); enhances conservation of water by the kidneys
Fluid from plasma passes into nephron, occurs in the glomerulus
Molecules are reabsorbed into the capillaries, occur in the tubule of the nephron
Molecules from blood are secreted unto nephron tubules, occurs as the filtrate moves through the tubule
Cell Membranes
Surrounds the cytoplasm, composed of two thin layers of phospholipids and proteins
Nitrogenous Waste
Excreted as urea, shows important evolutionary patterns
A characteristic that improves an organism's chance of surviving to reproduce
What nitrogenous wastes are excreted as
Uric Acid
Formed by in the body by the metabolism of protein and is excreted in the urine
Ion Balance
The correct balance of ions within cells