Exam 1 Top Hat Review Questions

Question 1

Pasteur’s experiments proved that ________.

Answer 1

preexisting cells present in the air can grow in sterilized nutrient broth

Question 2

What compounds was Stanley Miller able to create in his 1953 chemical evolution experiments?

Answer 2

Hydrogen cyanide, formaldehyde, and amino acids

Question 3

Which of these elements make up most of living matter?

Answer 3

Carbon, hydrogen, oxygen and nitrogen

Question 4

An atom consists of ____

Answer 4

protons, neutrons and electrons

Question 5

Bonds between two atoms that are equally electronegative are ________.

Answer 5

nonpolar covalent bonds

Question 6

A covalent bond is likely to be polar when ________.

Answer 6

one of the atoms sharing electrons is more electronegative than the other atom

Question 7

What types of bonds are broken when we boil water?

Answer 7

Hydrogen

Question 8

When the atoms involved in a covalent bond have the same electronegativity, what type of bond results?

Answer 8

A nonpolar covalent bond

Question 9

How many chemical bonds can carbon make?

Answer 9

4

Question 10

If a solution that has a high pH ( basic), the H+ concentration is:

Answer 10

Low

Question 11

Diet Pepsi solution has a high concentration of protons. What is the pH of Diet pepsi ( acidic, basic, neutral?)

Answer 11

Acidic

Question 12

What component of amino acid structure varies among different amino acids?

Answer 12

The components of the R-group (side chains)

Question 13

The primary structure of a protein:

Answer 13

is its amino acid sequence

Question 14

Which level of protein structure do the α-helix and the β-pleated sheet represent?

Answer 14

Secondary

Question 15

Fill in the blank. Alpha-helices have ⋯⋯⋯hydrogen bonds and beta pleated sheets have ⋯⋯⋯ hydrogen bonds.

Answer 15

intrastrand, interstrand

Question 16

Lipids that contain a high number of double bonds in their fatty acid chains will ________.

Answer 16

likely be liquid at room temperature

Question 17

Which component of phospholipids would be more comfortable interacting with water?

Answer 17

Polar heads

Question 18

For a fish to survive in the bottom of an Iowa pond over the winter, the fish needs to maintain fluid cell membranes. It can do so, if it has ……..

Answer 18

More unsaturated fatty acids in its membrane phospholipids

Question 19

When a membrane is freeze-fractured, the bilayer splits down the middle between the two layers of phospholipids. In an electron micrograph of a freeze-fractured membrane, the bumps seen on the fractured surface of the membrane are ________.

Answer 19

mostly integral and some peripheral proteins

Question 20

For a protein to be an integral membrane protein, it would have to be ________.

Answer 20

amphipathic, with at least one hydrophobic region

Question 21

Luciana’s microscope is equipped with a laser, and she is able to point the laser at a tiny spot on the cell membrane and bleach the GFPs in that spot. She continues to watch.
What will happen to the spot with time?

Answer 21

Grows smaller and eventually disappears

Question 22

Eukaryotic cells are generally larger than prokaryotic cells

Answer 22

True

Question 23

Which of the following macromolecules leaves the nucleus of a eukaryotic cell through pores in the nuclear membrane?

Answer 23

mRNA

Question 24

Which type of organelle or structure is primarily involved in the synthesis of oils, phospholipids, and steroids?

Answer 24

Smooth endoplasmic reticulum

Question 25

Which of the following is an example of potential rather than kinetic energy?

Answer 25

A molecule of glucose

Question 26

Which of the following accurately describes a reason why fats store more energy than carbohydrates?

Answer 26

Compared to carbohydrates, fatty acid chains have a higher ratio of bonds with high potential energy to bonds with low potential energy.

Question 27

A chemical reaction that has a positive ΔG is best described as ________.

Answer 27

Endergonic

Question 28

For living organisms, which of the following is an important consequence of the first law of thermodynamics?

Answer 28

The organism ultimately must obtain all of the necessary energy for life from its environment

Question 29

In an exergonic reaction …….

Answer 29

The reactants have more energy than products, and Energy is released, ΔG<0

Question 30

What is a high energy molecule in your cells that drives several anabolic reactions?

Answer 30

ATP

Question 31

The hydrolysis of ATP gives rise to ADP and iP and the reaction has a DG of -7.3 kcal/mol. We infer from this that the reaction is ………

Answer 31

exergonic and proceeds spontaneously

Question 32

Which has more free energy?

Answer 32

NADH

Question 33

The molecule that functions as the reducing agent (electron donor) in an oxidation-reduction reaction would have what characteristic?

Answer 33

loses electrons and loses potential energy