final

Question 1

Which of the following is NOT a characteristic of living organisms?

Answer 1

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a. High degree of complexity and organization
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b. Ability to extract, transform, and use energy
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c. Existence in a thermodynamic equilibrium with their surroundings
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d. Capacity for self-replication and evolution

Question 2

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Which of the following is a key difference between prokaryotic and eukaryotic cells?

Answer 2

a. Presence of ribosomes
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b. Presence of a plasma membrane
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c. Presence of a membrane-bound nucleus
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d. Presence of genetic material

Question 3

common functional group found in biomolecules?

Answer 3

amino, hydroxyl, carboxyl

Question 4

Which of the following statements about chiral molecules in living organisms is true?
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a. They are usually present in both forms (enantiomers).
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b. They are usually present in only one form.
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c. They do not bind stereospecifically.
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d. They have identical physical and chemical properties

Answer 4

hey are usually present in only one form.
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Question 5

What molecule is thought to have played a key role in the early evolution of life?

Answer 5

RNA

Question 6

The central dogma of molecular biology describes the flow of genetic information from:

Answer 6

DNA RNA to protein

Question 7

law of thermodynamics?

Answer 7

a. Energy cannot be created or destroyed. * b. The entropy of a system always increases. Energy can be transformed from one form to another.

Question 8

What type of thermodynamic system can exchange both matter and energy with its surroundings?

Answer 8

open system

Question 9

The ultimate source of energy for life on Earth is

Answer 9

sunlight

Question 10

example of anabolism?

Answer 10

synthesis of protiens from amino acid

Question 11

Example of catabolism?

Answer 11

cellualr respiration

Question 12

what is entropy

Answer 12

randomness or disorder

Question 13

Gibbs free energy (G) combines the concepts of enthalpy and entropy to determine:

Answer 13

spontaneity

Question 14

reaction is spontaneous if the change in Gibbs free energy (ΔG) is:

Answer 14

negative

Question 15

What process allows living organisms to drive energetically unfavorable reactions?

Answer 15

energy coupling

Question 16

The high-energy molecule that is often used for energy coupling in cells is

Answer 16

ATP

Question 17

What is the difference between ΔG° and ΔG’°?

Answer 17

ΔG° is the standard free-energy change at any pH, while ΔG’° is specific to pH 7.0 (biochemical standard conditions)

Question 18

An exergonic reaction is characterized by

Answer 18

A negative ΔG’° and a Keq > 1

Question 19

An endergonic reaction is characterized by:

Answer 19

A positive ΔG’° and a Keq < 1 *

Question 20

Which of the following statements about catalysts is FALSE? * a. They increase the rate of a chemical reaction. * b. They do not alter ΔG. * c. They lower the activation energy of a reaction. * d. They shift the equilibrium of a reaction.

Answer 20

shift equilibrium of reaction

Question 21

Feedback inhibition is a type of metabolic regulation wher

Answer 21

The end product of a pathway inhibits an enzyme earlier in the pathway.

Question 22

The geometry of a water molecule is best described as

Answer 22

Distorted tetrahedron

Question 23

The dipole moment of water arises from

Answer 23

The unequal sharing of electrons between oxygen and hydrogen.

Question 24

Hydrogen bonds are:

Answer 24

trong dipole-dipole or charge-dipole interactions

Question 25

Hydrogen bonds are strongest when:

Answer 25

he three atoms involved are in a linear arrangement.

Question 26

Which of the following properties of water is NOT a consequence of hydrogen bonding? a. High boiling point * b. High melting point * c. Large surface tension * d. Low density of ice

Answer 26

low density

Question 27

Why does ice float on liquid water?

Answer 27

ice is less dense