Question 1

When oxygen is bound to the heme group of myoglobin, it is coordinated between _____ and _____.

Accepted Answer

Oxygen is coordinated between the E7 histidine and the Fe²⁺ of the heme group in myoglobin.

Question 2

What is the prominent type of secondary structure observed in myoglobin?

Accepted Answer

Myoglobin is predominantly composed of $\alpha$-helices, which form the major secondary structure in this protein.

Question 3

While the composition of hemoglobin in adult humans is $\alpha$ ₂ $\beta$ ₂, in the developing fetus, _____ is observed

Accepted Answer

E

Question 4

Which of the following occurs in hemoglobin upon oxygen binding?

Accepted Answer

Upon oxygen binding, hemoglobin undergoes a conformational change from the T (tense) state to the R (relaxed) state, which decreases the size of the central cavity between the four subunits.

Question 5

Which of the following explains the conversion of hemoglobin subunits from deoxy to oxy state?

Accepted Answer

The answer of Which of the following explains the conversion...

Question 6

Which of the following fibers is correctly paired with the protein that forms the fiber?

Accepted Answer

All the pairings are correct: microfilaments are made of actin, microtubules are made of tubulin, extracellular support fibers often involve collagen, and intermediate filaments can be made of keratin.

Question 7

During the formation of microfilaments, which of the following occurs?

Accepted Answer

ATP hydrolysis is catalyzed by F-actin during the polymerization process, which helps in the dynamic instability and turnover of actin filaments.

Question 8

When a cell moves along a surface, actin _____ occurs at the leading edge while _____ occurs at the trailing edge

Accepted Answer

Actin polymerization occurs at the leading edge to push the cell forward, while depolymerization occurs at the trailing edge to retract the cell body.

Question 9

Which of the following details the nucleotide-binding site when tubulin dimers assemble into microtubules?

Accepted Answer

The answer of Which of the following details the nucleotide-binding...

Question 10

Which of the following explains how cell division is blocked by drugs that prevent proper microtubule function?

Accepted Answer

Microtubules form the spindle fibers that are essential for the separation of chromosomes during cell division. Drugs that disrupt microtubule function prevent the proper formation and operation of the spindle apparatus, thereby blocking cell division.

Question 11

What is the most prevalent secondary structure observed in the proteins of intermediate filaments?

Accepted Answer

Intermediate filaments are primarily composed of $\alpha$-helices, which form coiled-coil structures that provide mechanical strength.

Question 12

Which amino acid is critical for crosslinking of keratin fibers?

Accepted Answer

Cysteine (Cys) is critical for crosslinking keratin fibers through the formation of disulfide bonds, which provide strength and stability to the keratin structure.

Question 13

Ascorbic acid is required for the production of _____ in collagen.

Accepted Answer

Ascorbic acid is required for the production of hydroxyproline in collagen. Hydroxyproline is an amino acid that is found in collagen, and it is essential for the proper structure and function of collagen. Ascorbic acid is a cofactor for the enzyme prolyl hydroxylase, which is responsible for the hydroxylation of proline to hydroxyproline.

Question 14

The helical structure of collagen contains _____.

Accepted Answer

Collagen consists of three left-handed helices that are wound around each other to form a right-handed triple helix.

Question 15

Which amino acid is critical for crosslinking of collagen trimers?

Accepted Answer

Lysine is critical for crosslinking of collagen trimers through the formation of covalent bonds after being modified to hydroxylysine.

Question 16

Bone and tendons contain _____ while hair and nails contain _____.

Accepted Answer

Bone and tendons contain collagen, while hair and nails contain keratin. Collagen is a protein that provides strength and structure to connective tissues, while keratin is a protein that provides strength and protection to skin, hair, and nails.

Question 17

In a muscle cell, what is the name for the bundles of myosin tails?

Accepted Answer

The bundles of myosin tails in a muscle cell are known as thick filaments.

Question 18

Each myosin head contains a binding site for _____ and a binding site for _____.

Accepted Answer

Each myosin head has a binding site for actin, which allows it to attach to actin filaments, and a binding site for ATP, which provides the energy for muscle contraction.

Question 19

Which of the following correctly describes the sequence of events in the myosin-actin cycle?

Accepted Answer

In the myosin-actin cycle, ATP first binds to myosin, causing it to release from actin. Myosin then binds to another actin subunit, followed by the release of P_i and ADP, which allows the myosin to return to its original conformation.

Question 20

Each kinesin head contains a binding site for _____ and a binding site for _____.

Accepted Answer

Kinesin heads have a binding site for tubulin, which is part of the microtubule track they move along, and a binding site for ATP, which provides the energy for their movement.

Quiz 5: Protein Function

When oxygen is bound to the heme group of myoglobin, it is coordinated between _ and _.

What is the prominent type of secondary structure observed in myoglobin?

While the composition of hemoglobin in adult humans is $\alpha$ ₂ $\beta$ ₂, in the developing fetus, _____ is observed

Which of the following occurs in hemoglobin upon oxygen binding?

Which of the following explains the conversion of hemoglobin subunits from deoxy to oxy state?

Which of the following fibers is correctly paired with the protein that forms the fiber?

During the formation of microfilaments, which of the following occurs?

When a cell moves along a surface, actin _ occurs at the leading edge while _ occurs at the trailing edge

Which of the following details the nucleotide-binding site when tubulin dimers assemble into microtubules?

Which of the following explains how cell division is blocked by drugs that prevent proper microtubule function?

What is the most prevalent secondary structure observed in the proteins of intermediate filaments?

Which amino acid is critical for crosslinking of keratin fibers?

Ascorbic acid is required for the production of _____ in collagen.

The helical structure of collagen contains _____.

Which amino acid is critical for crosslinking of collagen trimers?

Bone and tendons contain _ while hair and nails contain _.

In a muscle cell, what is the name for the bundles of myosin tails?

Each myosin head contains a binding site for _ and a binding site for _.

Which of the following correctly describes the sequence of events in the myosin-actin cycle?

Each kinesin head contains a binding site for _ and a binding site for _.

Quiz 5: Protein Function

When oxygen is bound to the heme group of myoglobin, it is coordinated between _____ and _____.

What is the prominent type of secondary structure observed in myoglobin?

While the composition of hemoglobin in adult humans is α\alphaα 2 β\betaβ 2, in the developing fetus, _____ is observed

Which of the following occurs in hemoglobin upon oxygen binding?

Which of the following explains the conversion of hemoglobin subunits from deoxy to oxy state?

Which of the following fibers is correctly paired with the protein that forms the fiber?

During the formation of microfilaments, which of the following occurs?

When a cell moves along a surface, actin _____ occurs at the leading edge while _____ occurs at the trailing edge

Which of the following details the nucleotide-binding site when tubulin dimers assemble into microtubules?

Which of the following explains how cell division is blocked by drugs that prevent proper microtubule function?

What is the most prevalent secondary structure observed in the proteins of intermediate filaments?

Which amino acid is critical for crosslinking of keratin fibers?

Ascorbic acid is required for the production of _____ in collagen.

The helical structure of collagen contains _____.

Which amino acid is critical for crosslinking of collagen trimers?

Bone and tendons contain _____ while hair and nails contain _____.

In a muscle cell, what is the name for the bundles of myosin tails?

Each myosin head contains a binding site for _____ and a binding site for _____.

Which of the following correctly describes the sequence of events in the myosin-actin cycle?

Each kinesin head contains a binding site for _____ and a binding site for _____.

When oxygen is bound to the heme group of myoglobin, it is coordinated between _ and _.

While the composition of hemoglobin in adult humans is $\alpha$ ₂ $\beta$ ₂, in the developing fetus, _____ is observed

When a cell moves along a surface, actin _ occurs at the leading edge while _ occurs at the trailing edge

Bone and tendons contain _ while hair and nails contain _.

Each myosin head contains a binding site for _ and a binding site for _.

Each kinesin head contains a binding site for _ and a binding site for _.