ANSC 221 Final - Exam 1 Material

Which is the following is NOT an example of proteins in the cell membrane working together to perform a specialized function?

The enzyme sodium-potassium ATPase transports NA+ and K+, and catalyzes ATP

Which of the following amino acids is POLAR BASIC?

D

Lipids are not macromolecules because...

• They closely associate via hydrophobic interactions

• They are not composed of monomers

What does the Nuclear Envelope contain?

DNA

What does the Rough Endoplasmic Reticulum contain?

Ribosomes

What do Lysomes contain?

Acidic Solution

What does the Cell Membrane contain?

Cytosol

Which property of the peptide bond makes it particularly stronger compared to other covalent bonds

There is resonance of the double bond between oxygen, carbon, and nitrogen

Based on the structure of the fatty acid below, select all of the qualities that would be TRUE.

• Unsaturated fatty acid

• Cis fatty acid

• Liquid at room temperature

• Would provide fluidity to the cell membrane

Which of the following cellular junctions creates the water-tight connections between cells that are vital to epithelial tissues?

Tight Junctions

If you were designing an experiment where you needed to hold the pH of your reaction at 6.7, which of the following buffer systems would you choose?

Phosphate (pKa = 6.8)

What is specialized cargo of the smooth endoplasmic reticulum?

• Steroid hormones

• Xenobiotic-metabolizing enzymes

• Calcium ions

Ribosomes are not

What resulting change in protein function does Methylation cause?

Changes how strongly proteins interact with other macromolecules

What resulting change in protein function does Phosphorylation cause?

Modifies enzyme activity

What resulting change in protein function does Uniquitination cause?

Targets a protein for degradation

Molecules that dissolve in water are…

• Hydrophillic

• Polar

• Solutes

Define Polarity

Unequal sharing of electrons in a chemical bond

Define Electronegativity

Tendency for an atom to attract electrons towards itself

Define Dipoles

Molecules that have partial negative and partial positive charged regions

Define Ions

Atoms that carry a full positive or negative charge in solution due to loss or gain of electrons

If the highlighted groups in fructose below reacted to form a covalent bond, the resulting ring structure would be a:

Pyran

T/F: Phagocytosis is the least-specific form of bulk transport across the cell membrane (in terms of what is transported).

True

The carboxylic acid group of butyric acid (pictured below) at pH = 7.4 would mostly be...

Deprotonated (O-)

What is true regarding glycosidic bonds?

• It is named for the numbers of the two carbons connected

• Two of the same monosaccharide that come together via a glycosidic bond will not always have the same name

• It forms via a condensation reaction

False: It occurs between a ketone/aldehyde group and a hydroxyl group

What are examples of how the cytoskeleton helps provide the cell with MOTILITY?

• Microtubules form cilia and flagella

• Centrosomes interact with chromosomes during mitosis

• Motor proteins "walk" vesicles down microtubule highways

Which of the following amino acids is NONPOLAR?

A

For the lipid below, select all of the structural and functional classes to which it belongs:

• Glycerolipid

• Phospholipid

• Structural Lipid

• Energy Storage Lipid

In order for an induced dipole - induced dipole interaction to occur between two molecules, both molecules involved must be:

Non-Polar

Which of the following macromolecules contain oxygen?

• Carbohydrate

• Protein

• Nucleic Acids

What terms are in the structural category in relation to carbohydrate structure?

• Cellulose

• Linear Structure

What terms are in the energy storage category in relation to carbohydrate structure?

• Glycogen

• Branched Structure

In order for a transporter protein to function in a cell membrane, it must be:

An integral protein

Which of the following explains why the cell is not digested when lysosomes break down?

• The cytosol contains buffer systems

• Enzymes in the lysosome function most highly at acidic pH

Mitochondria and chloroplasts are highly specialized organelles in metabolism, thought to have originated via (this process):

Endosymbiosis

What letter refers to the Side Chain?

A

What letter refers to the Amino Group?

B

What letter refers to the Alpha Carbon?

C

What letter refers to the Carboxyl Group?

D

What makes up Intermediate Filaments?

Keratin

What makes up Microtubules?

Tubulin Heterodimers

What makes up Microfilaments?

Actin Homopolymers

T/F: Since water has a higher specific heat than air, water will tend to warm the air around it, buffering temperature changes.

True

Order the extracellular matrix network from the most outward (top, extracellular fluid) to the most inward (bottom, cytosol):

• Extracellular Fluid

• Glycoproteins and Proteoglycans

• Fibronectin

• Integrins

• Microfilaments

• Cytosol

Which of the following molecules can participate in Ionic Interactions?

• B

• C

• D

Which of the following scenarios is an example of Primary Active Transport?

The proton pump (H+ ATPase, a transporter) acidifies the lumen of lysosomes

Define Surface Tension

Strong interactions within a substance that allow it to resist stretching

Define Hydrogen Bonding

Chemical interaction that dictates water's properties

Define Cohesion

Chemical interactions that unite a substance (within that substance)

Define Adhesion

Chemical interactions that hold different substances close together (between substances)

In the picture below, the hydrogen bond DONOR is...

N+

What is the function of Signaling Lipids?

Facilitate communication between cells and tissues

What is the function of Structural Lipids?

Associate together to sequester and maintain cellular environments

What is the structure of Energy Storage Lipids?

Are oxidized to capture ATP

Order the following chemical interactions by their relative strength, with the strongest at the top:

Strongest

• Covalent Bond

• Ion-Dipole

• Hydrogen Bond

• Dipole-Inducced-Dipole

Weakest

T/F: According to the cisternal maturation model, vesicles flow from the trans face to the cis face of the golgi as their cargo is modified.

False

Which of the following molecules can participate in Hydrogen Bonding?

• A

• B

• C

• E

T/F: Testroses will form a furan ring structure in solution.

False

What is the function of the Rough Endoplasmic Reticulum?

Primary site of PROTEIN synthesis

What is the function of the Smooth Endoplasmic Reticulum?

Primary site of LIPID synthesis

What is the function of the Golgi?

Maturation and transport of biological molecules

What is the function of the Cell Membrane?

Provides selective permeability to the cell

What chemical interactions are Non-Polar?

• Hydrophobic

• Induced Dipole-

What chemical interactions are Polar?

• Hydrophillic

• Dipole-Dipole

What chemical interactions are Non-Polar and Polar?

• Amphipathic

• Dipole-Induced-Dipole

What is true about Lipid Rafts?

• Lipid rafts are composed of complimentary biological molecules to perform specialized functions

• Lipid rafts are enriched with sterols and sphingolipids

• Lipid rafts are enriched with protein-protein interactions

False: Lipid rafts are more fluid to allow them to move through the cell membrane

For the lipid below, select all of the structural and functional classes to which it belongs:

• Steroid

• Structural Lipid

• Signaling Lipid

Ribose would be described as:

• Pentose

• Aldose

• Monosaccharide

The pictured protein structure would be described as:

Alpha-helix

Based on their structure, would amylose or amylopectin make starch more difficult to digest (structurally stronger)? 

Amylose

T/F: Rapid depolymerization of microtubules (Catastrophe event) occurs when there are not enough GTP-bound subunits available to facilitate polymerization.

True

What is the function of Protein in the Cell Membrane?

Primarily provide FUNCTION

What is the function of Lipids in the Cell Membrane?

Primarily provide STRUCTURE

What is the function of Carbohydrates (Glycolipids and Glycoproteins) in the Cell Membrane?

Facilitates hydrophillic interactions