Bio

Which of the following describes the difference between a phospholipid and a fat?

Phospholipids have one less

fatty acid than fats.

Are lipids polymers or monomers?

Polymers

Which of the following describes the process to add a fatty acid to the glycerol in a triglyceride?

This is a dehydration reaction leading to water loss.

Which of the following describes why lipids are hydrophobic?

Lipids are composed mostly of hydrocarbons which is nonpolar.

Steroids are a type of hormone. Polar materials require a transport protein while nonpolar materials can pass easily through the plasma membrane. Which of the following describes how steroid hormones enter the cell?

Steroids are nonpolar so they pass easily through the plasma membrane.

Which of the following element(s) are found in lipids?

Carbon/hydrogen, oxygen, phosphorous

Which of the following describes the difference between saturated and unsaturated fatty acids?

Unsaturated fatty acids have more double bonds than saturated fatty acids.

Which of the following is not a lipid?

\
steroid

fat

lipase

phospholipid

Lipase

Phospholipids are amphipathic. Which of the following describes how that term applies to phospholipids?

The phosphate group is polar and the fatty acids are nonpolar.

Which of the following describes the function of cholesterol (a steroid) in the plasma membrane?

Cholesterol binds to the fatty acid tails to maintain fluidity of the membrane.

Which of the following describes the difference between a purine and a pyrimidine?

Pyrimidines are single ring structures while purines are double ring structures.

Which of the following is the monomer of a nucleic acid?

Nucleotide

Which of the following element(s) are found in nucleic acids?

Carbon/hydrogen, oxygen, phosphorous, nitrogen

Which of the following are purines?

Adenine, guanine

Which of the following describes a DNA strand that would be most stable at high temperatures?

25% A/T and 75% C/G

Which of the following describes the directionality of nucleic acids?

5' end has a phosphate and 3' end has a hydroxyl

If a researcher investigating a RNA strand discovers it contains 36% uracil, which of the following identifies the amount of cytosine?

Cannot be determined

Which of the following describes the base pairing and bonding involved with nitrogenous bases?

Adenine binds with Thymine with 2 hydrogen bonds

Which of the following is NOT one of the three groups comprising the nucleotide?

\
R group

phosphate

nitrogenous base

pentose sugar

R group

Which of the following are pyrimidines?

Cytosine, thymine, uracil

Which of the following element(s) are found in proteins?

Carbon/hydrogen, oxygen, sulfur, nitrogen

Which of the following describes the dehydration reaction of two amino acids?

Carboxyl group of first amino acid binds with amino group of second amino acid

The amino acid glutamic acid has a R group with a negative charge. During folding, which of the following describes the orientation of the R group?

Exterior of protein due to negative charge providing hydrophilic properties

Which of the following identifies the number of water molecules needed to remove the amino acids from a polypeptide with 20 amino acids?

19

Which of the following bonds is found in the secondary structure of a protein?

Hydrogen

Which of the following structures involves the R groups interacting in a single polypeptide?

Tertiary

In terms of directionality of the protein, which of the following provides naming for the side with the carboxyl group?

C - terminus

In terms of directionality of the protein, which of the following provides naming for the side with the amino group?

N - terminus

Which of the following is the monomer of a protein?

Amino Acid

Which of the following functional groups is found in all amino acids?

Amino, carboxyl

Which of the following is the structural polysaccharide found in the cell wall of plants?

Cellulose

Which of the following is the structural polysaccharide found in the cell wall of prokaryotes?

Peptidoglycan

If two glucose (C6H12O6) molecules undergo a dehydration reaction, which of the following represents the chemical formulas for the product(s)?

C12H22O11 + H2O

What polysaccharide are animals unable to break and why?

Cellulose due to beta glycosidic linkages

What element(s) are in carbohydrates?

Carbon/hydrogen, oxygen

Which of the following describe the process involved in metabolizing carbohydrates?

During hydrolysis, a water molecule is added to break the bond between the monosaccharide and the polysaccharide chain.

Which of the following is a monosaccharide?

Glucose

Which of the following are structural polysaccharides?

Cellulose, chitin

Which of the following are storage polysaccharides?

Glycogen, starch

Which of the following is the structural polysaccharide found in the cell wall of fungi?

Chitin

Describe what would happen if the mitochondrial inner membrane was ruptured.

ATP synthesis would be inhibited

What is the function of decoupling oxidative phosphorylation in the electron transport chain?

Generate heat to regulate body temperature in endotherms

Where does oxidative phosphorylation take place?

Cristae

How does the electron transport chain facilitate the synthesis of ATP?

The ATP is synthesized by the protons flowing down their concentration gradient after being pumped out by ETC

What does the NADH and/or FADH2 that is brought to the electron transport chain come from?

Glycolysis, krebs cycle, pyruvate oxidation

Where would you find the electron transport chain in a plant cell?

Mitochondrial cristae, thylakoid membrane, prokaryotic plasma membrane

What are the two parts of oxidative phosphorylation?

Electron transport chain, chemiosmosis

Which part of the cell will have the highest pH due to cellular respiration?

Matrix

How many ATPs are synthesized from the energy carried by NADH and FADH2 (on average)?

1 NADH = 3 ATP; 1 FADH2 = 2 ATP

Which direction are protons pumped during the electron transport chain?

Into the intermembrane space

How does the Krebs cycle allow for ATP synthesis?

High energy electrons are stored in NADH and FADH2 to shuttle to the ETC to generate a proton gradient

What is the difference between NADH and FADH2?

Both are electron carriers, NADH holds higher energy electrons

In one turn of the cycle, how many of the products are formed?

1 ATP, 3 NADH, 1 FADH2, 2 CO2

How are electrons extracted during the Krebs cycle transferred to the electron transport chain?

NADH, FADH2

Predict the effect of an inhibitor that stops the oxidation of NADH or FADH2.

Decrease of cellular respiration; less ATP is synthesized

How many turns of the Krebs cycle per glucose molecule?

2

How much of the glucose is left after the Krebs cycle?

0%

What is the starting material for the Krebs cycle?

Acetyl CoA

The Krebs cycle requires oxygen, because...

without oxygen, NADH cannot be oxidized to continue receiving electrons as NAD+

Where does the Krebs cycle take place?

Mitochondrial matrix

There are 10 steps in glycolysis, how many enzymes catalyze these steps?

10

Justify that glycolysis evolved before oxygen was present in the atmosphere.

Glycolysis does not require oxygen which represents that it evolved prior to free oxygen in the atmosphere.

What process takes place if NADH is unable to be oxidized?

Fermentation

Justify that glycolysis evolved prior to the mitochondria.

Glycolysis does not require a membrane which represents that it evolved prior to membrane bound organelles.

Where does glycolysis take place?

Cytosol

What is the main function of glycolysis?

To split the glucose molecule to release energy

What are the products of glycolysis?

2 ATP, 2 NADH, 2 pyruvate

Glycolysis requires oxygen.

False

How does glycolysis lead to ATP synthesis?

High energy electrons are stored in NADH for the ETC

What is the starting material for glycolysis?

Glucose

Which of the following is a way to overcome competitive inhibition of an enzyme?

Increase substrate concentration

Which of the following would NOT denature an enzyme?

LOW temperature

What happens to the reaction rate if an enzyme is denatured or nonfunctional?

Decrease in reaction rate

The delta G of a catalyzed reaction is 30 kJ/mol. If you double the reaction, what would be delta G of the catalyzed reaction?

30 kJ/mol

The decreased production of enzyme Trp-T would have which of the following responses?

Decrease in I3PA & IAA concentration

How does a noncompetitive inhibitor decrease reaction rates?

Binds to allosteric site

An enzyme can make an endergonic reaction into an exergonic reaction.

False

What is the function of an enzyme?

To speed up a chemical reaction

Where does a substrate bind to an enzyme?

Active site

Which of the following is NOT a way that enzymes speed up chemical reactions?

Increase required energy of activation

Which checkpoint involves determining whether the cell should divide?

G1

Which checkpoint involves ensuring all DNA has been replicated and "no" errors exist?

G2

Phase involving pairing of sister chromatids and condensation of chromatin into chromosomes

Prophase

Which of the following describes the result of mitosis?

2 identical, diploid cells

Phase involving microtubules to separate sister chromatids to opposite poles of cell

Anaphase

Which checkpoint involves ensuring all microtubules are attached to kinetochores?

M

Which of the following describes the order of processes in the cell cycle?

Interphase, Prophase, Metaphase, Anaphase, Telophase, Cytokinesis

Phase involving formation of nuclear envelope around separated chromosomes

Telophase

Phase involving sister chromatids aligning on plate in middle of cell

Metaphase

Which of the following occurs BEFORE the process of mitosis?

DNA is replicated

Where would you find a receptor for a steroid hormone?

In the cytoplasm because steroid are nonpolar

Which of the following is a potential response for the cell?

\
Conformational Change of Receptor

Transcription Factor

Phosphorylation Cascade

Release of Ca2+ from Smooth ER

Transcription Factor

How are ligands cell-specific?

Each cell has different receptors to bind to the ligand

More than one ligand can bind to the same receptor.

True

How is paracrine and hormone signaling different?

Hormone signaling involves bloodstream, long-distance and paracrine involves extracellular fluid, short-distance

How are steroid and protein hormones different?

Steroid hormones are hydrophobic while protein hormones are hydrophilic

Which of the following is the order of steps for a signal transduction pathway?

Reception -> Transduction -> Response

Describe the phosphorylation cascade.

Protein kinase adds a phosphate to a relay molecule which causes a change in shape to activate.

Where does the ligand bind to initiate signal transduction?

Receptor

Which of the following is a secondary messenger?

cAMP