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