Chapter 3 A&P HW
The sodium-iodide symporter plays a role in the accumulation of iodide in the thyroid gland. Here, one iodide gets converted to one iodine, which is utilized for the formation of either of the 2 types of thyroid hormones, T3 and T4. T3 and T4 are named after the number of iodines found in each of these hormones. To produce a single molecule of T3, a total of _______ sodium ions must move down their concentration gradients by secondary active transport. The movement of iodide ions occurs in the _____ direction as sodium ions.
6; same
Why do patients with cystic fibrosis have thick, sticky mucus in their lungs?
Their lung cells have faulty chloride pumps.
Ouabain is a poison that binds to the Na+/K+ pump in the cell membrane and inhibits its action. The expected result of this poison on secondary active transport is __________.
a loss of the ion concentration gradient that drives this process
The ligand for the sodium channel linked to an acetylcholine receptor is _________.
acetylcholine
Example of antiport
coupling of the inward movement of sodium ions with the outward movement of calcium ions
Water you drink is absorbed into the blood from the digestive tract. An increase in water intake causes a ________ in the plasma osmolarity.
decrease
Decreases rate of diffusion
decreased concentration gradient approaching diffusional equilibrium destruction of alveoli in the lungs due to emphysema
Passive Transport
diffusion filtration osmosis movement of molecules from an area of high concentration to an area of low concentration movement down a concentration gradient
Cuboidal
eccrine (sweat) secreting glands
Which membrane-bound organelle is the site of protein and lipid synthesis?
endoplasmic reticulum
A substrate binds to a receptor site forming the ____________ complex and releases products following catalysis of the chemical reaction.
enzyme-substrate
Integrins bind materials or cells in the ___________ matrix and use them to move through space.
extracellular
Simple and facilitated diffusion differ because _________.
facilitated diffusion requires the presence of a transport protein within the plasma membrane, while simple diffusion does not
After death, Na+-K+ pumps can continue to function indefinitely.
false
Glucose is passively absorbed through Na+-K+ pumps during secondary active transport.
false
Na+-K+ pumps bind ATP in the ECF.
false
Na+-K+ pumps move 3 molecules of sodium to the ICF per cycle.
false
Na+-K+ pumps move sodium down its concentration gradient.
false
Use of the term "pump" refers to moving solutes down their respective concentration gradients.
false
Osmosis moves water out of blood
freshwater fish placed in a saltwater aquarium protein deficiency causing low levels of blood albumin intravenous delivery of hypotonic solution
The movement of water by osmosis is always from a ________.
high to low water concentration
Some individuals have defective genes for LDL receptors rendering them nonfunctional. Individuals with these mutations typically have _________.
higher than normal blood cholesterol levels due to inability of peripheral cells to uptake LDLs.
A cell placed into which solution will lose water by osmosis?
hypertonic
Physiological saline is a solution containing 0.9% NaCl. A cell in 1.5% NaCl is in a _________ solution.
hypertonic
An IV solution of 0.45% NaCl is ________ and includes the movement of water _______.
hypotonic; into cells
Increases rate of diffusion
increased temperature decreased molecular weight increased membrane surface area increased membrane permeability decreased cell height, creating a flatter cell villi and microvilli in the intestinal epithelium increased synthesis of channel proteins
Columnar
intestinal cells with microvilli
Receptor-mediated endocytosis
involves clathrin-coated pits.
A ____________ channel allows a constant flow of sodium through the plasma membrane down its own electrochemical gradient.
leaky sodium
An individual displaying a larger than normal number of LDL receptors is _______ likely to develop artherosclerosis.
less
A __________ channel allows for discriminatory permeability of solutes only at designated times.
lingand-regulated
Cytoplasm
membrane-enclosed enzymes used to hydrolyze cellular components the organelle responsible for sorting and packaging proteins the network of protein filaments and cylinders that structurally support the cell the "powerhouse" of the cell the clear, gelatinous component of the cell
Primary and secondary active transport proteins differ in that primary active transport proteins ________.
move both molecules against their gradients, while secondary active transport proteins couple the movement of an ion down its gradient with the movement of another molecule against its gradient
The Na+/K+ ATPase moves sodium in the ________ direction compared with the direction it travels through sodium leakage channels.
opposite
Certain white blood cells engulf microorganisms and bring them in to digest them. This process is best described as __________.
phagocytosis
The majority of the plasma membrane can be described as a bilayer of ______ with associated proteins.
phospholipid
Active Transport
pinocytosis vesicular transport sodium-potassium pumps movement up a concentration gradient receptor-mediated endocytosis
Hemolysis
placing a red blood cell in distilled water placing a red blood cell with an ICF concentration of 0.9% NaCl into a solution with 0.1% NaCl placing a red blood cell into a hypotonic solution
Crenation
placing a red blood cell into a hypertonic solution placing a red blood cell with a concentration of 0.9% NaCl into a solution of 1.5% NaCl
No change
placing a red blood cell into an isotonic solution
Cell membrane
proteins that allow ions to enter and leave the cell extensions that serve primarily to increase the cell's surface area hair-like processes that may function as antennae and/or aid in motility proteins whose surfaces contact both the ICF and the ECF the fuzzy coat made of glycolipids and glycoproteins
Insulin, a hydrophilic compound, binds to a ________ site on the cell's extracellular surface, causing activation of a second messenger system on the cell's interior.
receptor
Exocytosis is a process by which cells _________.
release substances from the cell via vesicles
Squamous
respiratory membrane
The organelles that read coded genetic messages and assemble amino acids into proteins are called ______.
ribosomes
Osmosis moves water into blood
saltwater fish placed in a freshwater aquarium soft-tissue crush injury releasing potassium into the blood stream acute, bolus ingestion of NaCl high blood sugar consumption of sea water
Circulating plasma antibodies recognize a _______________ as "self" and thus do not initiate an immune response.
surface glycoprotein
Sugars can be transported into cells against their concentration gradient because of _______.
symport with sodium ions
The directional movements of ions by facilitated diffusion through protein channels is determined by ______.
the electrochemical gradient of the ion being transported
Which of the following is the most direct source of energy for cotransport?
the movement of one of the transported substances down its concentration gradient
Microvilli
to increase the cell surface area and facilitate transport
Mitochondria
to produce ATP via cellular respiration
Na+-K+ pumps are active forms of transport.
true
Na+-K+ pumps are enzymes that hydrolyze ATP into ADP and Pi.
true
Na+-K+ pumps consume about half of your daily energy expenditure.
true
Na+-K+ pumps have 6 binding sites for reactants (3Na+, 2K+, and 1 ATP).
true
Microvilli
used for absorption increases the surface area of the cell contain the brush border enzymes of the intestines
Nonmotile "Primary" Cilia
used for sensation located in the inner ear, nasal cavity, and retina as sensory receptors
Motile Cilia
used to move fluids on outer surface of the cell utilizes rhythmic movement utilizes ATP for movement contains molecular motors
Changes in the membrane potential trigger the opening or closing of ________.
voltage-gated channels
