Bio module 3 SG

What is generally the maximum magnifying capacity of a light microscope

2000

What is typically the result of receptor up regulation

A hormones signal is amplified

Why is it advantageous for cells to be small

A small cell has a small volume relative to surface area which allows efficient transport through the plasma membrane

What does ABC transporter use to move larger ions and molecules across the cell membrane

ATP

Which neurotransmitter opens ligand-gated sodium channels

Acetylcholine

while testing an experimental drip on a vertebrate you notice that the cell vortex becomes more fluid and the cell loses its ability to move. Despite this you determine that cell strength is maintained. Based on these observations you correctly conclude that the drug most directly affects

Actin filaments

DNA is associated with certain proteins, forming a complex called:

Chromatin

Once ligand molecules binds to receptors in coated pits of a plasma membrane the next step of receptor-mediated endocytosis would be

Coated vesicle forms by endocytosis

The following are different types of neurotransmitters except

Cyclic adenosine

When food is scarce the amoeba-like cellular slime mold dictyostelium secretes which compound

Cyclic adenosine monophosphate

Name the part of the cell outside the nucleus

Cytoplasm

During enzyme-linked reception, signal molecules bind to two tyrosine kinase receptors. The receptor proteins move closer together in the plasma membrane and pair, forming a(n) ____.

Dimer

Scaffold proteins ensure that signals are relayed

Efficiently

Phosphate comes from ATP

Enzyme linked receptor

Protein kinase sites are active

Enzyme linked receptor

Which cellular mechanism ejects products such as hormones by the fusion of a vesicle with the plasma membrane

Exocytosis

Enzymes called protease sin the ER lumen catalyze folding of proteins into proper conformations

False

In cell membranes cholesterol and glycoproteins are exposed to the extra cellular surfaces for cell recognition and adhesion to other cells

False

In scanning electron microscopy, an electron beam passes through a very thin slice of specimen and then falls onto a photographic plate or a fluorescent screen

False

Kinesin transports organelles toward the minus end of a microtubule

False

Mitochondria play an important role in cell necrosis

False

Plasmolysis occurs in plant cells when the soil or water contains low concentration of salts or fertilizers

False

When an enzyme linked receptor is activated a conformational change activated the extra cellular kinases

False

A basal body anchors what part of a cell

Flagellum

In the sodium-potassium pump, sodium ion release causes the carrier protein to return to its original shape and releases two K+ ions into the cell

Flase

Which of the following is necessary for a cell to maintain its function and growth

Food

The hydrolysis of GTP to GDP deactivates the

G protein

DAG is the second messenger

G protein linked receptor

GDP is replaced with GTP

G protein linked receptor

What protects a cell and may help keep other cells at a distance

Glycocalyx

Which strategy is the most effective for larger cells to have an effective surface area to volume ratio

Having thin finger like projections

Fluid that has a higher osmotic pressure than a cell is called

Hypertonic

If the concentration of solutes in a cell is less than the concentration of solutes in the surrounding fluid then the extra cellular fluid is said to be

Hypertonic

In the phospholipase C signal transduction pathway which pair of second messengers is produced

IP3 and DAG

Which of the following pairs is correctly matched

Integrins-receptors

Sodium ions enter the cell

Ion channel linked receptor

A transmembrane protein differs from other membrane proteins because

It completely extends through the membrane

A patient who has had a severe hemorrhage accidentally receives a large transfusion of distilled water directly into a major blood vessel. What effect will this have on the patient

It will have serious perhaps fatal consequences because the red blood cells could swell and burst

The ratio of the size of the image seen with the microscope to the actual size of the object is called

Magnification

Sodium-potassium pumps help to maintain a desperation of charges across the plasma membrane which is called the

Membrane potential

Which one of these are the most convenient unit for measuring cells

Micrometer

You isolate a cellular structure and determine that it is composed of a-tubulin and b-tubulin. Based on this evidence, you correctly identify this structure as a

Microtubule

Which of the following organelles plays an important role in apoptosis or programmed cell death

Mitochondria

Which two organelles are responsible for converting energy into forms that can be used by cells

Mitochondria and chloroplasts

Which of the following serves as a framework for the orderly distribution of chromosomes during cell divisions

Mitotic spindle

What can happen when GABA binds to its receptor

Neural signaling is inhibited

What transmits information electrically and chemically

Neurons

A single cell in a smokers lung has become cancerous it doubles its DNA and divides much faster than a normal lung cell. The most likely change that would have caused this condition took place in the..

Nucleus

Which statement about G protein is false

One subunit binds ATP

Specialized structures within a living cell are known as

Organelles

What method does a human white blood cell employ to employ to engulf a bacterial cell

Phagocytosis

Which statement about plasma membranes is false

Plasma membranes prevent communication with other cells

Which molecule is least likely to cross a cellular membrane by simple diffusion

Potassium ion

Choanoflagellates are important in the study of cell communication evolution because choanoflagellates have

Protein kinases similar to those in animals

If the cells are physically close to one another a signaling molecule on one cell may combine with a ..... on another cell

Receptor

Which is a part of a signal transduction pathway that enables vision in dim light in vertebrates

Rhodopsin

What does the nucleolus within the nucleus synthesize

Ribosomal RNA

What is the process in which one activated receptor can give rise to a thousands of final products

Signal amplification

The outer part of a G protein linked receptor binds to a ........ and it's inner part binds to a ......

Signaling molecule; G protein

You light a scented candle in the guest bathroom. Within a few minutes you can smell the candles scent throughout the hallway. What process is occurring?

Simple diffusion

What type of molecule can rapidly cross a plasma membrane

Small, hydrophobic molecules

How does the scanning electron microscope differ from the transmission electron microscope

The SEM yields a 3D image of the object being studied

Evidence that all living cells have a common origin is best illustrated by

The basic similarities in cell structure and chemistry

In cells that are constantly involved in secretion an equivalent amount of membrane must be returned to the interior of the cell for each vesicle that fuses with the plasma membrane if this does not occur then what would happen

The cell surface will keep expanding

In cells that are constantly involved in secretion an equivalent amount of membrane must be returned to the interior of the cell for each vesicle that fuses with the plasma membrane; if this does not occur then what would happen

The cell surface will keep expanding

Which statement about centrioles is false

The have a 9+2 arrangement of microtubules

The term fluid mosaic model refers to

The movement of lipids and integral proteins within the lipid bilayer

Under which of the following situations would receptor downregulation most likely occur

The number of receptors in the plasma membrane is too low

In the cAMP signal transduction pathway a protein kinase is activated. What happens next

The protein kinase activates a cellular response.

Scaffold proteins organize groups of intracellular signaling kinases into signaling complexes

True

The gas ethylene is a plant hormone that regulates a variety of processes including seed germination and ripening of fruit

True

The many short appendages that a cell has are called cilia

True

What process halts the net movement of water from a hypotonic solution into a plants cells and often provides the structural support to many plants?

Turf or pressure

Peripheral proteins are linked to either surface of the plasma membrane by

bonding to integral proteins through noncovalent interactions.

Phosphodiesterase catalyzes the conversion of

cAMP to AMP

When the net movement of water in and out a cell is zero that solution is said to be

isotonic

Which of the following is a key component of the cytoskeleton

microtubules

Cells that secrete large amounts of glycoproteins have many golgi stacks

True

How are hormones produced by endocrine glands typically transported to target cells

By the blood

The smooth ER is the primary site for the synthesis of phospholipids and cholesterol needed to make

Cell membranes

What happens during the Curran's port of glucose and sodium ions

The transport of glucose powers the transport of sodium; glucose molecules are transported against their concentration gradient

What happens when Ras proteins become stuck in their "on" state

There is unregulated cell division

Which statement about receptors is false

They are also called ligands

How are integral proteins unique in cell membranes

They are firmly bound to the membrane

Which statement about Ras proteins is false

They are inactivated when phosphorylated

Which of the following statements about phospholipids is flase

They contain three fatty acid chains

Which of the following is not a property of membranes

They inhibit the passage of materials

The role of ATP in the sodium-potassium pump is

To assist a Na+ to bind to a carbohydrate

Most intracellular receptors are what type of protein

Transcription factors

Carrier proteins are also called

Transporters

Almost every vertebrate cell has a primary cilium, a single cilium on the cell surface that serves as a cellular antenna

True