Chapter 3
the fluid outside the cell
ECF (extracellular fluid)
the peripheral microtubules forming the core of a cilium extend into the cell and are anchored with a _________
basal body
The sodium-potassium pump maintains a high sodium ion concentration in the cell.
false
A high concentration of water has ____________ dissolved particles than a low water concentration
fewer
in blood capillaries, blood pressure forces fluid through gaps in the capillary wall in a process called _______
filtration
a membrane coating called the ________ is chemically unique in everyone but identical twins
glycocalyx
An IV solution of 0.45% NaCl is ________________ and induces the movement of water ________________.
hypotonic; into cells
accumulated cell products such as glycogen granules, pigments, and fat are types of __________
inclusions
name the membrane-bound organelles that contain enzymes and oxygen to be used to oxidize organic material
peroxisomes
the movement of two solutes simultaneously through a plasma membrane in the same direction uses a carrier type called a ____________
symport
describe the types of molecules that readily diffuse through a cell membrane
-nonpolar molecules -lipid-soluble molecules -hydrophobic molecules
intestinal surface area is increased by extensions of the cell membrane
Celiac disease, which decreases the absorptive surface area of the small intestine
Which of the following statements about receptor-mediated endocytosis is true?
It involves clathrin-coated pits.
chromosomes are housed with in the nuclear envelope
Trisomy 21 (Down's Syndrome), which is caused by an extra 21st chromosome
The ligand for the sodium channel in this animation is ___________.
acetlycholine
___________ ____________ is an enzyme which converts ATP to cyclic AMP
adenylate cyclase
the membrane channels that allow movement of water across a membrane are called:
aquaporins
the transmembrane proteins or protein clusters with pores that allow water and dissolved ions to pass through the membrane are called ion __________
channels
the molecule primarily responsible for stiffening the cell membrane is _______
cholesterol
name the fine thread-like genetic material (the form of DNA) found within the nucleus of a non-living cell
chromatin
the process involving an antiport carrier moving solutes in opposite directions across a cell membrane, and does not require energy is called ________ transport
counter
Water you drink is absorbed into the blood from the digestive tract. An increase in water intake causes a(n) ___________________ in the plasma osmolarity.
decrease
A reduction in the number of glucose carrier proteins within the plasma membrane _____________ the rate of glucose diffusion.
decreases
the fluid contained inside the cells is known as ___________ fluid
intracellular
the brush border on the apical surface of cells is composed of cellular extensions comprised of actin are _________
microvilli
the _________ is perforated with pores to allow material to move in and out of the nucleus
nuclear envelope
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
in the actions of __________, a substance is taken up at one side of a cell and released from the other side. This allows substances to be transported across an entire cell
transcytosis
a carrier that transports only one type of solute at a time is called an _______
uniport
Changes in the membrane potential trigger the opening or closing of __________.
voltage-gated channels
decreases rate of diffusion
-decreased concentration gradient -approaching diffusional equilibrium -destruction of the alveoli in the lungs due to emphysema
passive
-diffusion -filtration -osmosis -movement of molecules from an area of high concentration to an area of low concentration -movement down a concentration gradient
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
increases rate of diffusion
-increased temp. -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
membranous organelles
-nucleus -mitochondria -lysosomes -endoplasmic reticulum -golgi complex
active
-pinocytosis -vesicular transport -sodium-potassium pumps -movement up a concentration gradient -receptor-mediated endcytosis
non-membranous structures/organelles
-ribosomes -centrosomes -centrioles -glycogen -cytoskeleton
osmosis moves water into blood
-saltwater fish placed in a freshwater aquarium -soft tissue crush injury releasing potassium into the blood stream -acute, blus ingestion of NaCl -high blood sugar -consumption of sea water
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
desmosomes are collections of proteins embedded in cell membranes that anchor one cell to its neighboring cell
Pemphigus, which is a genetic/immune disorder, compromises proteins that hold adjacent cells together in the skin.
The ligand binds to
sodium ions directly.
The sodium-potassium pump functions to pump ___________.
sodium ions out of the cell and potassium ions into the cell.
Sugars can be transported into cells against their concentration gradient because of __________.
symport with sodium ions
During one cycle, the sodium-potassium pump binds and moves __________.
3 Na+ and 2 K+.
tubulin is one protein of the cytoskeleton that contributes to intracellular transport
A defect in tubulin proteins inhibits the ability to position organelles inside a cell.
exocytosis describes the movement of chemicals from the ICF to the ECF and requires secretory vesicles
A neurotoxin that prevents exocytosis
adipose cells are noted for having large membrane bound vacoules
Obesity, which is caused by energy imbalance, leads to larger than normal deposits of lipids in adipose cells.
What is the source of energy used to power the sodium-potassium pump?
breakdown of ATP
the glucose part of a glycolipid
carbohydrate chains
these membrane proteins bind one cell to another
cell-adhesion molecule (CAM)
these membrane proteins help to distinguish the body's own cells from foreign cells
cell-indentity marker
plays an important role in mitosis
centriole
polygonal cells
circular/polygon shape
the golgi complex is composed of about six flattened membranous sacs called ___________
cisternae
aerobic ATP production occurs in double membraned organelles
cyanide poisoning, which blocks aerobic production of WTP
During osmosis, water will move ____________ its own concentration gradient until equilibrium has been reached.
down
these membrane proteins break down a chemical messenger and terminate its effects
enzyme
Cellular products such as hormones and neurotransmitters are released by the process of __________.
exocytosis
encloses proteins in vesicles
golgi complex
these membrane proteins constantly allow ions to pass into and out of the cell
ion channel
An individual displaying a larger than normal number of LDL receptors is _____________ likely to develop artherosclerosis.
less
contains digestive enzymes
lysosome
the powerhouse of the cell
mitochondria
contains DNA
nucleus
The Na+/K+ ATPase moves sodium in the __________ direction compared with the direction it travels through sodium leakage channels.
opposite
may contact either the ICF or ECF
peripheral protein
Phagocyosis and pinocytosis differ in that __________.
phagocytosis allows for the transport of larger particles than pinocytosis
has both hydrophilic and hydrophobic parts
phospholipid bilayer
these membrane proteins bind to chemical messengers
receptor
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 two 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.
six; same
detoxifies alcohol in liver cells
smooth endoplasmic reticulum
Which of the following is an example of antiport?
Coupling of the inward movement of sodium ions with the outward movement of calcium ions
The Na+/K+ ATPase moves sodium in the __________ direction compared with the direction it travels through sodium leakage channels.
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.
Opening of the sodium channel
allows the diffusion of Na+ ions into the cell.
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
Simple and facilitated diffusion differ because __________.
facilitated diffusion requires the presence of a transport protein within the plasma membrane, while simple diffusion does not
these membrane proteins open and close to allow ions through only at certain times
gated ion channel
The ____________________ determines if glucose moves into or out of the hepatocyte.
glucose concentration between the intracellular and extracellular fluid
a phospholipid molecule with a carbohydrate covalently bonded to it
glycolipid
a protein with a carbohydrate covalently bonded to it
glycoprotein
Lysosomes are membrane-bound vesicles that arise from the __________.
golgi apparatus
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
The lysosome contains ________ enzymes.
hydrolytic
Physiological saline is a solution containing 0.9% NaCl. A cell in 1.5% NaCl is in a(n) __________ solution.
hypertonic
Which of the following cells will be expected to contain the most active lysosomes?
phagocytosing white blood cells
Certain white blood cells engulf microorganisms and bring them in to digest them. This process is best described as __________.
phagocytosis
The most specific type of endocytosis is __________.
receptor-mediated endocytosis
Exocytosis is a process by which cells ___________.
release substances from the cell through pores in the cell membrane
studded with ribosomes
rough endoplasmic reticulum
Osmosis is the net flow of water from one side of a ____________ permeable membrane to the other.
selectively
The directional movement of ions by facilitated diffusion through protein channels is determined by __________.
the electrochemical gradient of the ion being transported
When the acetylcholine binds to the receptor sites..
the sodium channels open which causes sodium ions to diffuse through and enter the cell.
When the acetylcholine receptor sites are not occupied __________.
the sodium channels remain closed.
Both symport and antiport require transport proteins.
true
If a cell is placed in an isotonic medium, there will be no net movement of water.
true
If the material the cell takes in is liquid, the process is termed pinocytosis.
true
Lysosomes function in the destruction and recycling of old organelles.
true
The binding and release of sodium or potassium ions are due to conformational changes in the protein.
true
The enzymes found in the lysosomes were formed in the endoplasmic reticulum.
true
The sodium channel is said to be voltage-gated
true
The sodium channels in the cell membrane have receptor sites for acetylcholine.
true
The sodium-potassium pump is a trans-membrane protein.
true
This channel is formed by a channel protein.
true
When the ligand is not bound, the sodium channel remains closed.
true
The normal movement of water across this membrane is from high to low ____________ concentration
water
