Bio 180 Final

Listed below are the equilbrium constants for a number of reversible chemical reactions. Order them (smallest to largest) from that which most favors reactants to that which that most favors products. 1001 1x10-5 0.5 0.00035 1x103 0.0021 1.35

(6) 1001 (1) 1x10-5 (3) 0.5 (1) 0.00035 (5) 1x103 (2) 0.0021 (4) 1.35

Clinicians will often administer 5% glucose intravenously (IV) to patients. What is the molarity of a 5% glucose solution? (Hint: glucose has molecular weight of 180)

.278

the backbone of an RNA strand is composed of phosphate and sugars. How many phosphates are there for every sugar inthe backbone?

1

Water molecules hydrogen bonding to other mater molecules is called ______. While water molecule experiencing electrostatic attraction molecules other than water is called ______.

Cohesion; Adhesion

Which of the following statements is a logical consequence of the second law of thermodynamics?

Every chemical reaction must increase the total entropy of the universe

What is the following molecule? crimpy =O ----OH

Fatty acid

which of the following would be most likely to readily dissolve in water

KCl

Which of the following cytockeletal proteins is not associated with a known motor protein

Keratin

Larger more complex molecules like glucose ahve more potential energy than smaller less complex molecules like carbon dioxide because

Glucose has more chemical bonds than carbon dioxide

Which of the following are primarily responsible for cytokinesis in plant cells but no in animal cells

Golgi-derived vesicles

you see a nitrogenous base taht is made of two cyclic rings and can make 3 hydrogen bonds. It is

Guanine

Which of the following molecules contains a carbonyl group

H----C=== O H----

A certain channel protein in the cell membrane is equally permeable to both Na+ and K+. Na+ concentrations are high on the outside of the cell (which is positive), while K+ concentrations are high on the inside of the cell (which is negative). Assuming equal concentration gradients for both Na+ and K+, which of the following statements is true regarding the movement of these ions through this channel?

More Na+ ions will be transported

Which of the following is not one of the elements making up 96% of living matter

Na

Cells from an advanced malignant tumor most often have very abnormal chromosomes, and often an abnormal total number of chromosomes. Why might this occur?

chromosomally abnormal cells can still go through cell cycle checkpoints

The cytochrome b-f protein in photosynthesis is analogous to ......... in cell respiration

comlex III

The amino acid isoleucine belongs to the non-polar amino acids due to the nature of its side chain. Its side chain is most likely made of which functional group

alkyl group

Ribose is a significant carbohydrate because...

it is a component of nucleotides

what are the scaffolding proteins

large molecules to which several relay proteins attach to facilitate cascade effects

Binding of signaling molecule to which type of receptor leads directly to a change in distribution of ions on opposite of the membrane

ligand-gated ion channel

lactose

dimer

maltose

dimer

sucrose

dimer

Vinblastine is a drug used to treat cancer. it interferes with the assembly of microtublules; therefore, its effectiveness in treating cancer must relate to

disruption of the mitotic spindle

Glucose diffuses very slowly through artificial phospholipid bilayers. The cells lining the small intestine, however, rapidly move large quantities of glucose from the glucose-rich food into their glucose-poor cytoplasm. Using this information, which transport mechanism is most probably functioning in the intestinal cells?

facilitiated diffusion

The inner membrane monolayer of organelle membranes is called the cytosolic leaflet

false

Which of the following can be effective in preventing the onset of viral infection in humans?

getting vaccinated

which of the following is not an adantage of internal membranes

greater control of mobility

Which of the following pairs has a relationship such that the second term is always a member of the first term

integral membrane proteins: Transmembrane proteins

chromosomes align at an impaginary plane equidistant between the 2 poles of the cell during

metaphase

following molecule? O OH OH

nucleotide

DNA is a polymer of repeating units called

nucleotides

which of the following monolayers is called a cytosolic leaflet

outer layer of the oranellular membrane

Which of the following are true regarding pKa.

pKa is the negative log of the Ka pKa is the pH when the conjugate base and weak acid are at the same concentration pKa is physical characteristic of each unique buffering system pH=pKa+log(A-/HA)

Amylopectin

polymer

amylose

polymer

cellulose

polymer

chitin

polymer

glycogen

polymer

On a hot day, a plant will close its stomata inorder to

prevent loss of water

Which of the following categories of endocytosis is regulated by cellular receptors?

receptor-mediated endocytosis phagocytosis

which of the follwoing stages requires ATP

reductions stage and ribulose regeneration stage

Insulin binds to its receptor on the liver causing the liver to store glucose as glycogen A cell surface receptor on a fibroblast cell receives a signal from a growth factor causing the cell to produce a cyclin which leads to its progression through the cell cycle Testosterone binds it receptor in a skeletal muscle cell which leads to this muscle growing larger (hypertrophy) is response to exertion. Cells surrounding the site of an infection release chemical signals which are 'sensed' by white blood cells and allows them to migrate toward the site of infection.

regulate enzyme activity regulate gene transcription regulate gene transcription activate movement of cytoskeleton

The genome of a bacterial cell is sequenced and several remnants of phage DNA are uncovered. The most likely explanation is

transduction has occured

The outer monolayer of the plasma membrane is called the extracellular leaflet true or false

true

calvin cycle stages

1. carbon fixation 2. carbon reduction 3. ribulose regeneration

How many total ATP are produced by 3 glucose molecules through the various glycolytic pathways

12

Lead-210 (Z=82) decays by alpha emission. What is the mass number of the resulting atom.

206

Assume a mitochondrion contains 58 NADH and 19 FADH2. If each of the 77 dinucleotides were used, approximately how many ATP molecules could be generated as a result of oxidative phosphorylation (chemiosmosis)?

212

Neon has 10 electrons. How many of those electrons fill 2p orbitals?

6

You have a cellulose chain consisting of 120 glucose residues. You also have 40 monomeric glucose residues. You place both in water and perform multiple condensation reactions until all reactants are gone. Which of the following best describe the product(s) of your reactions?

A cellulose chain with 160 residues and 40 water molecules

Protein phosphorylation is commonly involved with all of the following EXCEPT? A) a. regulation of transcription by extracellular signal molecules. B) b. enzyme activation. C) c. activation of G protein-coupled receptors. D) d. activation of receptor tyrosine kinases. E) e. activation of protein kinase molecules.

C) activation of Gprotein coupled receptors

Which of the following bonds would result in a partial charge on the bonded atoms?

C-O

which of the following is a protien maintained at constant levels throughout the cell cycle that requires cyclin to become catalytically active

Cdk

Determine if the statement in quotations is true or False. If false, identify one of the corrections below that make it a true statement. "The oligosaccharides that sometimes decorate membrane proteins are only found on the cytosolic monolayer of the plasma membrane."

Change cytosolic to extracellular

Whcih of the following describes the sequence of electron carriers inthe electron transprot chain, starting with the least electronegative?

FMN,Fe*S, ubiquinone, cytochromes

True or false. Denatured proteins can still carry out normal functions but at a much lower level.

False

Use the following words to fill in the blanks in this sentence. Each word will be used once. Head Tail Phosphate Hydroxyl The 5' end of a nucleic acid is considered the _______________. It is characterized by the presence of a _____________ functional group. While the 3' end is considered the _________. It is characterized by the presence of a _____________ functional group.

Head, phosphate, tail, hydroxyl

The free energy for the oxidation of glucose to CO2 and water is -686 kcal/mole and the free energy for the reduction of NAD+ to NADH is +53 kcal/mole. Why are only two molecules of NADH formed during glycolysis when it appears that as many as a dozen could be formed?

Most of the free energy available form the oxidation of glucose remains in pyruvate, one of the products of glycolysis

Which of the following molecules is not possible

O=C-C-C-C-N

A hallmark of cancer cells is anchorage independence - the ability to grow on a surface that does not resemble the cell�s native microenvironment. Along with the availability of growth factors and the density of cells surrounding the cancer cells, anchorage independence in normal cells is linked to the key environmental checkpoint in the cell cycle. As such, which of the following is true?

Signal transduction pathways form properly adhered cells would most likely result in the transcription of cyclin

Which of the following statements correctly describes the nomal toncicity conditions for typical plant and animal cells

The animal cell is isotonic solution and the plant cell is in a hypotonic solution

WE sometimes use the term asymmetric to describe a memebrane. What does this mean?

The inner surface of the membrane has a different look, feel and functionthan the outside of the membrane

Biologists sometimes utilize biological molecules that contain radioactive isotopes in place of stable isotopes. One example is tritiated thymidine. Thymidine is a building block of DNA and some of the hydrogen atoms within this molecule have been replaced with a radioactive isotope that contains two neutrons and one proton called tritium. Which of the following describe the properties of radioactive isotopes that make them useful in biology (select all that apply): (1.6)

The particles emitted from radioactive isotopes such as tritium are detectable even at low levels making them useful for sensitive biological experiments.

A researcher lyses a cell that contains nucleic acid molecules and capsomeres of tobacco mosaic virus (TMV). The cell contents are left in a covered test tube overnight. The next day this mixture is sprayed on tobacco plants. Which of the following would be expected to occur?

The plants would develop the typical symptoms of TMV infection

ATP has three different structural regions. Which of the following regions is primarily responsible for the energy transfers that ATP carries out in the cell?

The poly phosphate

density-dependent inhibition is explained by which of the following?

as cells become more numerous, the cell surfcae proteins of one cell contact the adjoining cells and they stop dividing

A major group of G protein-linked receptors contain seven transmembrane alpha helices. The amino terminus of the protein lies at the exterior of the plasma membrane. Loops of amino acids connect the helices either at the exterior face or on the cytosol face of the membrane. The loop on the cytosol side between helices 5 and 6 is usually substantially longer than the others. Where would you expect to find the carboxyl terminus?

at the cytosol surface

With respect to question on G protein coupled receptors, the coupled G protein most likely interacts with this receptor

at the loop between H5 and H6

Which of the following is true about the passage of water across a cell membrane

because water is polar, it cannot easily cross the cell membran

buffers are substances that help ressit shifts in pH

both donating H to a solution when bases are added and accepting h when acids are added

What explains the increase concentration of Ca2+ in the ER?

calcium ions are actively imported from the cytoplasm into the ER

which of the following is a protein synthesized at specific times during the cell cycle that associates with a kinase to form a catalytically active complex

cyclin

Which of the following is true regarding the periodic table:

each element in a group (column) of the periodic table will ahve the same valence shell electron configuration

Changing the temperature or pH will alter the activity of an enzyme. Enzymes are made or destroyed when a cell needs or doesn't need to catalyze a particular reaction. ) A regulator will bind to an enzyme at a site other than the active site and cause a conformational shift either activating or inhibiting the enzyme. A regulator produced by an enzyme or by a subsequent enzyme in a metabolic pathway will decrease the activity of the enzyme. Enzymes are localized to compartments or membranes within a cell in order to regulate their function.

environmental regulation temporal regulation allosteric regulation feedback inhibition spatial regulation

GTPase activity is involved in the regulation of signal transduction because it

hydrolyzes GTP binding to G protein

Which of the following most accurately describes how a siganl is propagated by a phosphorylation cascade

in a series, kinase use ATP to transfer a phosphate to protein substrates

Which of the following is true for the signaling system in an animal cell that lacks the ability to produce GTP?

it would not be able to activate and inactivate the g protein on the cyotplasmic side of the plasma membrane

kinase or phosphatase Action of this enzyme leads to a conformational shift in substrate which usually activates the protein substrate's enzymatic function.

kinase

kinase or phosphatase Transfers a phosphate from ATP to substrate generating ADP and a phosphorylated substrate.

kinase

Which of the following accurately represents the units of molarity?

moles/Liters

deoxyribose

monomer

fructose

monomer

galactose

monomer

glucose

monomer

ribose

monomer

What is the most common source of genetic diversity in prokaryotes?

mutation

glycoprotein or glycolipid on cell surface

oligomer

The covalent link between two amino acids forming a polypeptide chain is called a

peptide bond

which of the following types of bonds holds the primary structure of a protein intact

peptide bond

Which of the following is NOT a purpose of cellular signal transduction pathways?

permits genetic material to be passed by a virus into a cell

Which of the following organelles is NOT a member of the endomembrane system?

peroxisomes

kinase or phosphatase Usually this enzyme's action will lead to Inactivation of protein substrates

phosphatase

kinase or phosphate Removes phosphate from substrate generating inorganic phosphate (Pi) and dephosphorylated substrate

phosphate

An inhibitor of which of the following could be used to block the release of calcium form the endoplasmic reticulum?

phospholipase C

why is ATP an important molecule in metabolism

provides energy coupling between exergonic and endergonic reactions

Succinate dehydrogenase catalyzes the conversion of succinate to fumarate. The reaction is inhibited by malonic acid, which resembles succinate but cannot be acted upon by succinate dehydrogenase. Increasing the ratio of succinate to malonic acid reduces the inhibitory effect of malonic acid. Based on this information, which of the following is correct?

succinate is the substrate and fumarate is the product

cytokinesis typically occurs during

telophase

if a pharmaceutical company wished to design a compound

that increases phosphodesterase activity

Which of the following best defines the term specific heat

the amount of enregy required to raise 1 g to of liquid to 1 Celcius

The process of oxidative phosphorylation can be likened to a battery that powers a water pump as well as a turbine which is powered by the pumped water. In this analogy the proton motive force best can be represent by which of the following:

the force of the movement of the pumped water down through a turbine

Which of the following span the phospholipids bilayer, usually a number of times?

transmembrane proteins

The process of transduction usually begins

when the siganl molecule changes the receptor protein in some way