Chapter 2 BIOPORTAL (PT1)

Question 1

Acids have a pH __________ than 7.

Answer 1

Less

Question 2

The sulfhydryl functional group is found in the class of compounds known as

Answer 2

thiols.

Question 3

Multiple atoms linked together are called:

Answer 3

a molecule.

Question 4

Water molecules form which type of bond with other water molecules?

Answer 4

Hydrogen bonds

Question 5

Which of the following properties is a result of hydrogen bonding between water molecules?

Answer 5

the ability of ice to float in water
high specific heat
the ability to dissolve polar substances
high surface tension

Question 6

what is the smallest form an element can take?

Answer 6

a single atom

Question 7

When transporting water up to the top of giant trees, which feature allows water molecules to pull up adjacent water molecules to which they have bonded?

Answer 7

cohesion.

Question 8

The hydroxyl functional group is found in the class of compounds known as

Answer 8

alcohols.

Question 9

Energy used in cellular respiration can originate from

Answer 9

carbohydrates, proteins, and fats.

Question 10

Acetic acid is an important example of a class of compounds known as

Answer 10

carboxylic acids.

Question 11

The four most abundant elements in living organisms are:

Answer 11

hydrogen, nitrogen, oxygen, and carbon

Question 12

The chemical characteristics of an atom depend upon which of the following?

Answer 12

the number of electrons in the outermost shell

Question 13

In an uncharged atom, the number of protons and ___________ must be equal.

Answer 13

electrons

Question 14

Carbon, is considered versatile when it comes to bonding with other atoms and making important compounds. Which feature of carbon most contributes to this versatility?

Answer 14

carbon can share its four outermost electrons with other atoms

Question 15

The atomic number of an element is:

Answer 15

the number of protons in the nucleus of one atom.

Question 16

Just four elements make up more than 96% of the human body. These include:

Answer 16

carbon, oxygen, hydrogen, and nitrogen

Question 17

Which of the following are all monosaccharides?

Answer 17

glucose, fructose, and galactose

Question 18

Water can absorb and store a large amount of heat while increasing only a few degrees in temperature because

Answer 18

the heat must first be used to break the hydrogen bonds rather than raise the temperature.

Question 19

A covalent bond is formed when:

Answer 19

two atoms share electrons.

Question 20

Evaporation from the leaves of a tree will pull water up through the roots as an unbroken column throughout the entire height of the tree. This feat is possible because of which characteristic(s) of water?

Answer 20

cohesion

Question 21

All macromolecules important in living systems contain:

Answer 21

Carbon

Question 22

The most effective way to reduce the risk of _______ is to limit our intake of ___________ .

Answer 22

heart disease, saturated fats

Question 23

An substance similar to table salt, called magnesium chloride, separates into positively charged magnesium ions and negatively charged chloride ions when placed in water. If one were to look at the magnesium ions dissolved in the water, what would you see?

Answer 23

The magnesium ions would be surrounded by water molecules with their oxygen atoms facing the magnesiums.

Question 24

Pure water and aqueous solutions that are neither acidic nor basic are said to be:

Answer 24

neutral.

Question 25

Which of the following elements have 4 electrons in their outer shells?

Answer 25

carbon and silicon

Question 26

Covalent bonds are bonds in which:

Answer 26

two atoms share electrons.

Question 27

Male gypsy moths are attracted by airborne chemicals that bind to receptors on their antennae. Only the correctly shaped molecule will fit into the receptors, stimulating an attraction. This is a demonstration of which fundamental biological concept?

Answer 27

The specific structure of something determines how that part interacts with other things.

Question 28

A chemical compound that releases H+ into a solution is called a(n):_____________.

Answer 28

Acid

Question 29

Buffers are substances that minimize the changes that occur in H+ and OH- concentrations. A buffer works by accepting _______ from the solution when there is an excess and donating them when there is a deficiency.

Answer 29

hydrogen ions

Question 30

One important difference between covalent and ionic bonds is that:

Answer 30

in covalent bonds two atoms share electrons while in ionic bonds one atom gives one or more electrons to the other atom.

Question 31

Acetic acid is an important example of a class of compounds known as

Answer 31

carboxylic acids.

Question 32

The nucleus of an atom is usually made up of:

Answer 32

protons that have a positive charge and neutrons that have no electrical charge.

Question 33

The functional group -NH2 is called:

Answer 33

Amino