The Chemical Level of Organization

In the reactions that occur in metabolism, enzymes function as

A. amino acids

B. lipids

C. catalysts

D. compounds

C. catalysts

What kind of bond is formed between two separate water molecules?

A. a hydrogen bond

B. an ionic bond

C. a covalent bond

A. a hydrogen bond

Molecules form because of…

A. the shape of the individual atoms

B. the attraction between electrons

C. transfer or sharing of electrons

D. a drive toward solubility

C. transfer or sharing of electrons

adding hydrogen ion (H⁺) to a solution would...

A. raise the pH making the solution more acidic

B. lower the pH making the solution more basic

C. raise the pH making the solution more basic

D. lower the pH making the solution more acidic

D. lower the pH making the solution more acidic

Organic compounds always contain ___________ atoms.

A. water

B. carbon

C. nitrogen

D. oxygen

A. water

The pH of the blood is slightly basic.  Which of the following describes this pH?

A. 6.4

B. 4.6

C. 8.2

D. 7.4

D. 7.4

Which of the following is a molecule?

A. Na⁺

B. Mg

C. Cl^-

D. H₂O

D. H₂O

Water has . . . .

A. a low heat capacity

B. a high heat capacity

B. a high heat capacity

Molecules that readily dissolve in water are said to be...

A. hydrophobic

B. hydrophilic

B. hydrophilic

Which of the following is a nucleic acid?

A. DNA

B. RNA

C. both DNA and RNA

D. None of the choices are correct

C. both DNA and RNA

The positively charged particles in the nucleus of an atom are…

A. neutrons

B. electrons

C. protons

D. isotopes

C. protons

All enzymes are…

A. nucleic acids

B. carbohydrates

C. proteins

D. lipids

C. proteins

Glycogen is…

A. a monosaccharide

B. a disaccharide

C. the stored form of glucose in plants

D. the stored form of glucose in animals

D. the stored form of glucose in animals

Which of the following are "polysaccharides"? (Mark all that apply)

A. glucose

B. cellulose

C. glycogen

D. starch

E. simple sugars

B. cellulose, C. glycogen, D. starch

Polypeptides are…

A. chains of three or more amino acids

B. chains of three or more nucleic acids

C. chains of three or more fatty acids

A. chains of three or more amino acids

What type of reaction is being shown here?

A. hydrolysis

B. dehydration synthesis

B. dehydration synthesis

True or False: Lipids are hydrophilic

True

Which elements are present in all carbohydrates (mark all that apply)

A. oxygen

B. carbon

C. nitrogen

D. phosphorus

E. hydrogen

A. oxygen, B. carbon, E. hydrogen

Amino acids are linked together by…

A. steroids

B. peptide bonds

C. ionic bonds

D. hydrogen bonds

B. peptide bonds

phospholipid

The subunit molecules for proteins are…

A. atoms

B. amino acids

C. enzymes

D. polymers

B. amino acids

an amino acid 

hydrolysis

Because of its chemical structure, _______________ cannot be digested by humans and broken down into monosacchardes.   Therefore, humans don't get energy directly from this carbohydrate.

A. starch

B. fiber

C. disaccharides

D. glycogen

B. fiber

Which organic compounds  are always insoluble in water?

A. water

B. lipids

C. nucleotides

D. proteins

B. lipids

2 - hydrolysis

1 - dehydration synthesis

2 - hydrolysis

1 - dehydration synthesis

Adding hydroxide (OH^-) to a solution would...

A. raise the pH making the solution more basic

B. lower the pH making the solution more basic

C. raise the pH making the solution more acidic

D. lower the pH making the solution more acidic

A. raise the pH making the solution more basic

Cell membranes are made primarily of __________.

A. cholesterol

B. phospholipids

C. carbohydrates

D. nucleic acids

B. phospholipids

Low levels of radiation are commonly used to…

A. sterilize dental products

B. destroy cancer cells

C. produce images of body parts

D. All of these choices are correct

D. All of these choices are correct

Buffers…

A. decrease the pH of a solution

B. always promote a pH of 7

C. resist changes in pH

D. increase the pH of a solution

C. resist changes in pH

Which element is present in all proteins, but is NOT present in lipids or carbohydrates?

A. hydrogen

B. oxygen

C. carbon

D. nitrogen

D. nitrogen

Glucose is a…

A. a simple carbohydrate found only in plants

B. a complex carbohydrate found only in animal cells

C. a complex carbohydrate that contains many starch molecules

D. simple carbohydrate used by the body for energy

D. simple carbohydrate used by the body for energy

An ion is an atom or molecule that…

A. is in a gaseous state

B. carries an electrical charge

C. is attracted to a north-seeking pole

D. forms a visible glow

B. carries an electrical charge

True or False: Carbohydrates such as glucose (C₆H₁₂O₆) are considered "organic molecule.

True

The differences between one polypeptide and another lies in…

A. the type of peptide bond they contain

B. the type of sugar they contain

C. whether they are saturated or not

D. the sequence of amino acids

D. the sequence of amino acids

Which of the following statements is true?

A. a solution with pH 4 is 100 times more basic than a solution with a pH of 6.

B. a solution with pH 4 is 20 times more basic than a solution with a pH of 6.

C. a solution with pH 4 is 20 times more acidic than a solution with a pH of 6.

D. a solution with pH 4 is 100 times more acidic than a solution with a pH of 6.

D. a solution with pH 4 is 100 times more acidic than a solution with a pH of 6.

The pH of pure water is...

A. 0

B. 5

C. 7

D. 10

E. 12

C. 7

Organic" molecules always contain...

A. carbon and hydrogen

B. sodium and potassium

C. nitrogen and phosphorus

D. oxygen and sulfur

A. carbon and hydrogen

ATP (Adenosine Triphosphate) is a special…

A. nucleotide

B. lipid

C. carbohydrate

D. protein

A. nucleotide

The smallest unit of matter is the…

A. molecule

B. atom

C. compound

D. tissue

B. atom

Which of the following is made from glucose?

A. protein

B. fat

C. nucleic acid

D. starch

D. starch

Estrogen and Testosterone are steroids which would be classified as which type of organic molecule?

A. nucleic acid

B. lipid

C. carbohydrate

D. protein

B. lipids

The four categories of organic molecules found in cells are...

A. carbohydrates, water, proteins, and starch

B. carbohydrates, lipids, proteins, and nucleic acids

C. lipids, fiber, water, and amino acids

D. polysaccharides, monosaccharides, disaccharides, and cellulose

B. carbohydrates, lipids, proteins, and nucleic acids

Compounds that form ions when put into water are called…

A. mixtures

B. solvents

C. salts

D. suspensions

C. salts

Which of the following correctly shows the relationship between ATP and ADP?

A. ADP --> Phosphate + ATP

B. ATP --> ADP  + Phosphate

C. ATP + Phosphate --> ADP

D. ATP + ADP  --> Phosphate

B. ATP --> ADP  + Phosphate

Which part of a water molecule has a slightly positive charge?

A. the oxygen atom

B. the hydrogen atoms

C. the entire molecule is positively charged

B. the hydrogen atoms

The chemical formula for glucose is…

A. C₆H₁₂O₆

B_. C₁₂H₂₂O₁₁

C. C₁₂N₆

D. C₆H₂

A. C₆H₁₂O₆

Which type of chemical bond forms when atoms share pairs of electrons?

A. covalent

B. hydrogen

C. ionic

D. both convalent and hydrogen are correct

A. covalent

Acids are substances that (when added to water) increase the number of _______________.

A. hydroxide ions (OH-)

B. oxygen atoms

C. hydrogen ions (H+)

D. carbon atoms

C. hydrogen ions (H+)

The lower the pH,…

A. the greater the hydrogen ion concentration

B. the more alkaline the solution

C. both of the choices are correct

D. neither answer is correct

A. the greater the hydrogen ion concentration

Which of the following contains high-energy phosphate bonds?

A. DNA

B. glycogen

C. RNA

D. ATP

D. ATP

The most abundant molecule in living organisms is…

A. water

B. oxygen

C. glucose

D. saline

A. water

Glycogen is…

A. a monosaccharide used for quick energy

B. a protein found in cell membranes

C. a polysaccharide used as stored energy

D. a fat found in margarine

C. a polysaccharide used as stored energy

dehydration synthesis

steroid

Match each to the category of either “acid” or “base”

1. pH 7.9

2. pH 3

3. High H+ concentration

4. 4. pH 9

1. base

2. acid

3. acid

4. base

Match each as corresponding with either “DNA” or “RNA”

1. double-helix

2. deoxyribose sugar

3. single strand

4. uracil base

1. DNA

2. DNA

3. RNA

4. RNA

A. dehydration synthesis

B. hydrolysis

B. hydrolysis

1 - solution

2 - solute

3 - solvent