Chapter 2: Chemistry of Life

Question 1

What is a covalent bond?

Answer 1

When atoms share electrons to fill the outer electron shells.

Question 2

What is a hydrogen bond?

Answer 2

A bond that forms between a hydrogen atom and an oxygen/nitrogen atom. (it is a weak bond; holds water molecules together)

Question 3

What is adhesion?

Answer 3

When two different molecule substances stick together.

Question 4

What is cohesion?

Answer 4

When the same molecule substances stick together

Question 5

What is a hydrogen ion? What is a hydroxide ion?

Answer 5

When a water molecule (H2O) splits, one half is a hydrogen ion (H+). The other half is a hydroxide ion (OH-).

Question 6

What is the pH scale?

Answer 6

The scale tracking how much H+ and OH- are in certain liquids.

Question 7

What is neutral on the pH scale and why?

Answer 7

7 is neutral. It is neutral because there is an equal amount of H+ and OH- in it.

Question 8

What is an acid?

Answer 8

An acid is when a liquid has more H+ in it than OH-. It also has a pH level of 1-6.

Question 9

What is a base, or alkaline?

Answer 9

A base is when a liquid has more OH- than H+ in it. It also has a pH level of 8-14.

Question 10

What is a buffer?

Answer 10

A buffer is a natural or manmade liquid to help keep a pH level the same. For example, living organisms have buffers in their bloodstream to help keep the blood’s pH the same.

Question 11

What does homeostasis mean?

Answer 11

Homeostasis is a term used when describing a stable internal environment. Basically, it means “the same”.

Question 12

What are CHONPS?

Answer 12

The most important major elements in living things:
Carbon
Hydrogen
Oxygen
Nitrogen
Phosphorus
Sulfer

Question 13

What determines the pH level in organisms?

Answer 13

The amount of hydrogen and hydroxide ions.

Question 14

True/False: Carbon is the most important element in living things.

Answer 14

True. Carbon is the most important, followed closely by Hydrogen and Nitrogen.

Question 15

What are the four major organic compounds?

Answer 15

Carbohydrates, lipids, nucleic acids, and proteins.

Question 16

What is an ionic bond?

Answer 16

When atoms transfer electrons so both have full outer electron shells.

Question 17

A _______ molecule has a carbon backbone and is found in all living things.

Answer 17

-Organic- molecule.

Question 18

What is another term for a lipid?

Answer 18

Fat(s).

Question 19

What atoms are carbohydrates made out of?

Answer 19

C, H, O. (in a 1:2:1 ratio)

Question 20

What function do carbs provide?

Answer 20

Provides “quick” energy.

Question 21

What are the building blocks of carbohydrates?

Answer 21

Simple carbs/single sugars/monosaccharides

Question 22

What do you have if you have two single sugars?

Answer 22

Disaccharide.

Question 23

What do you have if there are multiple single sugars?

Answer 23

Polysaccharide.

Question 24

What atoms are lipids made out of?

Answer 24

C, H, O (in no specific ratio)

Question 25

What do lipids provide?

Answer 25

Long term energy storage; building component of membranes and waterproofing.

Question 26

What are the building blocks of lipids?

Answer 26

Glycerol and fatty acids.

Question 27

Which is healthier: saturated or unsaturated fat?

Answer 27

Unsaturated fat (oil).

Question 28

What atoms are nucleic acids made up of?

Answer 28

C, H, O, N, P

Question 29

What do nucleic acids provide?

Answer 29

They store and transmit genetic information/codes.

Question 30

What are the building blocks for nucleic acids?

Answer 30

Nucleotides (Phosphate, sugar, base)

Question 31

What atoms are proteins made out of?

Answer 31

C, H, O, N (sometimes S)

Question 32

What do proteins provide?

Answer 32

Lots of things – can control the rate of reactions, cell processes, forms bone and muscle, can move substances in and out of cells, fights diseases, etc…

Question 33

What are the building blocks in proteins?

Answer 33

Amino acids.

Question 34

What is a metabolism?

Answer 34

The chemical reactions that are going on inside living organisms.

Question 35

What is a catalyst?

Answer 35

Something that speeds up a reaction by lowering the amount of activation energy.

Question 36

What is an enzyme?

Answer 36

A special protein that is like a catalyst – it helps speed up certain reactions in living organisms. It is also known as a complex protein.

Question 37

True or false: Enzymes can be used over and over again.

Answer 37

True! An enzyme is not worn out after it is ised so it can keep being reused.

Question 38

When an enzyme is used, the reaction starts with the same _________ and ends with the same ________.

Answer 38

Reactants; products.

Question 39

When will enzymes work best?

Answer 39

At a certain pH level (buffers - important!) and a certain temperature (reaction is faster as heat rises but if it’s too high then the enzyme will be destroyed…)

Question 40

What is the pattern for nucleotides?

Answer 40

Phospherous, sugar, base. Phospherous, sugar, base. Phospherous, sugar, base…