D3.3 HL only Flashcards
nitrogen containing compounds
essential building blocks of living organisms. Amino acids, nucleic acids, and nucleobases are key biological nitrogen compounds
nitrogenous waste
any waste product that is nitrogen-based.Nitrogenous wastesare formed when proteins are broken down into amino acids for energy. Ammonia is the most basic form of nitrogenous waste and is formed from the remaining amino acids that occur in the breakdown of proteins
NH3
ammonia (NH3),colourless, pungent gas composed of nitrogen and hydrogen.
urea
an organic compound with the chemical formula CO (NH2)2. It is produced in the liver and serves as the metabolic by-product of protein and nitrogen metabolism
uric acid
a chemical created when the body breaks down substances called purines
kidneys
One of a pair of organs in the abdomen. The kidneys remove waste and extra water from the blood (as urine) and help keep chemicals (such as sodium, potassium, and calcium) balanced in the body
Osmolarity
the number of dissolved solute particles per liter of solution
Excretion
the process of removing wastes and excess water from the body
Osmoregulation
maintenance by an organism of an internal balance between water and dissolved materialsregardless of environmental conditions
Dehydration
A condition that occurs when the body loses too much water and other fluids that it needs to work normally
hypertonic
a solution with a comparatively greater solute concentration than that in another solution
Hyperhydration
when the body takes in more water than it loses. Overhydration can occur when people drink much more water than their body needs
hypotonic
solutions having a low amount or concentration of the non-penetrating solutes in comparison to the other solution across asemipermeable membrane
osmotic potential
The ability of water molecules to migrate over a semipermeable membranefrom a hypotonic solution (more water, fewer solutes) to a hypertonic solution
renal vein
The main blood vessel that carries blood from the kidney and ureter to the inferior vena cava
renal artery
large blood vessels that carry blood from your heart to your kidneys
cortex
The cortex surrounds the inside of the organ, which is called themedulla. The renal cortex itself is covered by the renal capsule, which is a layer of tougher protective tissue. The renal cortex is where the nephrons (blood-filtering units) begin
medulla
the inner part of the kidney. The medulla helps regulate the concentration of urine by filtering out water, salts, and acid
pelvis
a funnel collecting the urine produced in the kidney, leading to a central “stem,” the ureter
ureter
The tube that carries urine from the kidney to the bladder
bladder
the organ that stores urine
urethra
The tube through which urine leaves the body. It empties urine from the bladder.
nephron
the basic structural and functional unit of the kidney. They are the microscopic structure composed of arenal corpuscleand a renal tubule
bowman’s capsule
a part of the nephron that forms a cup-like sack surrounding the glomerulus
glomerulus
the main filtering unit of the kidney. It is formed by a network of small blood vessels (capillaries) enclosed within a sac called the Bowman’s capsule
afferent arteriole
a group of blood vessels that supply the nephrons in many excretory systems. They play an important role in the regulation of blood pressure as a part of the tubuloglomerular feedback mechanism
efferent arteriole
a blood vessel in the urinary system that brings filtered blood from the glomerulus to the rest of the kidney and back to the general circulation
ultrafiltration
a process in the kidney by which urea, salt, water and glucose etc. is extracted from the blood
fenestrations
any small opening or pore
basement membrane
a ribbon-like extracellular matrix that lies between the endothelium and thepodocytefoot processes
podocyte
specialized visceral epithelial cells which regulate glomerular filtration
filtrate
The liquid that passes through a filter
proximal convoluted tubule (PCT)
a segment of the renal tubule responsible for the reabsorption and secretion of various solutes and water. The PCT is located in the renal cortex, the outer part of the kidney, and is the first segment of the renal tubule, where it receives the filtrate from the renal corpuscle
Selective reabsorption
the process whereby certain molecules (e.g. ions, glucose and amino acids), after being filtered out of the capillaries along with nitrogenous waste products (i.e. urea) and water in the glomerulus, are reabsorbed from the filtrate as they pass through the nephron
microvilli
finger-shaped plasma membrane protrusions that are found at the surface of a large variety of cell types but are most numerous and elaborated on simple epithelial
secondary (indirect) active transport
The molecule of interest is then transported down theelectrochemical gradient. While this process still consumes ATP to generate that gradient, the energy is not directly used to move the molecule across the membrane, hence it is known as secondary active transport
symport
Proteins that move two molecules in the same direction across the membrane
osmosis
the movement of water molecules from a solution with a high concentration of water molecules to a solution with a lower concentration of water molecules, through a cell’s partially permeable membrane
The loop of henle
long U-shaped portion of the tubule that conducts urine within each nephron of the kidney of reptiles, birds, and mammals
descending limb
the portion of the renal tubule constituting the first part of the loop of Henle. Descending limb of loop of Henle. Scheme of renal tubule and its vascular supply
ascending limb
a direct continuation from thedescending limb of loop of Henle, and one of the structures in the nephron of the kidney. The ascending limb has a thin and a thick segment
collecting ducts
The last part of a long, twisting tube that collects urine from the nephrons (cellular structures in the kidney that filter blood and form urine) and moves it into therenal pelvisand ureters
antidiuretic hormone (ADH)
A hormone that helps blood vessels constrict and helps the kidneys control the amount of water and salt in the body
permeability
the relative ability of solutes to diffuse through the lipid bilayer barrier of membranes.
aquaporins
channel proteins from a larger family of major intrinsic proteins that form pores in the membrane of biological cells, mainly facilitating transport of water between cells
counter-current multiplier
the process in which energy is used to create an osmotic gradient that enables the reabsorption of water from the tubular fluid, so that urine can be concentrated
osmoreceptors
a sensory cell located in the hypothalamus that detects changes inosmolalityand stimulates the secretion of antidiuretic hormone (AVP) to regulate water balance in the body
hypothalamus
The area of the brain that controls body temperature, hunger, and thirst
pituitary gland
sometimes called the “master” gland of the endocrine systembecause it controls the functions of many of the other endocrine glands. The pituitary gland is no larger than a pea, and is located at the base of the brain
vasoconstriction
the narrowing (constriction) of blood vessels by small muscles in their walls
vasodilation
the widening of blood vessels due to the relaxation of the blood vessel’s muscular walls
