Chapter 2- Chemical Level of Organization

Question 1

How are the electrons of carbon distributed between the first and second electron shells?

Answer 1

2 in the first shell, 4 in each shell after

Question 2

What are the 4 major elements in the human body?

Answer 2

oxygen, carbon, hydrogen, and nitrogen

Question 3

What are the 8 lesser elements in the human body?

Answer 3

calcium, phosphorus (P), potassium (K), sulfur (S), sodium, chlorine (Cl), magnesium (Mg), and iron (Fe; ferrum = iron)

Question 4

Ionic bond

Answer 4

An ionic bond is the force of attraction that holds together oppositely charged ions. Gives/gaines electrons

Question 5

cation vs anion

Answer 5

A cation is a positively charged ion; an anion is a negatively charged ion.

Question 6

covalent bond

Answer 6

In a covalent bond, two atoms share one, two, or three pairs of electrons in the outer shell.

Question 7

concentration in reactions

Answer 7

The more particles of matter present in a confined space, the greater the chance that they will collide (think of people crowding into a subway car at rush hour). The concentration of particles increases when more are added to a given space or when the pressure on the space increases, which forces the particles closer together so that they collide more often.

Question 8

temperature in reactions

Answer 8

As temperature rises, particles of matter move about more rapidly. Thus, the higher the temperature of matter, the more forcefully particles will collide, and the greater the chance that a collision will produce a reaction.

Question 9

Prostaglandins

Answer 9

A membrane-associated lipid; released in small quantities and acts as a local hormone.

Question 10

Ribonucleic acid (RNA)

Answer 10

A single-stranded nucleic acid made up of nucleotides, each consisting of a nitrogenous base (adenine, cytosine, guanine, or uracil), ribose, and a phosphate group.

Question 11

A triglyceride that is a solid at room temperature.

Answer 11

fat

Question 12

Metabolism

Answer 12

All the biochemical reactions that occur within an organism, including the synthetic (anabolic) reactions and decomposition (catabolic) reactions.

Question 13

Nucleic acids

Answer 13

An organic compound that is a long polymer of nucleotides, with each nucleotide containing a pentose sugar, a phosphate group, and one of four possible nitrogenous bases (adenine, cytosine, guanine, and thymine or uracil).

Question 14

Catalysts

Answer 14

Chemical compounds that speed up chemical reactions by lowering the activation energy needed for a reaction to occur.

Question 15

Lipoproteins

Answer 15

One of several types of particles containing lipids (cholesterol and triglycerides) and proteins that make it water soluble for transport in the blood.

Question 16

Free radical

Answer 16

An atom or group of atoms with an unpaired electron in the outermost shell. It is unstable, highly reactive, and destroys nearby molecules.

Question 17

Saturated fat

Answer 17

A fatty acid that contains only single bonds (no double bonds) between its carbon atoms; all carbon atoms are bonded to the maximum number of hydrogen atoms; prevalent in triglycerides of animal products such as meat, milk, milk products, and eggs.

Question 18

Antioxidants

Answer 18

A substance that inactivates oxygen derived free radicals. Examples are selenium, zinc, beta carotene, and vitamins C and E.

Question 19

nucleus

Answer 19

A spherical or oval organelle of a cell that contains the hereditary factors of the cell, called genes. A cluster of unmyelinated nerve cell bodies in the central nervous system. The central part of an atom made up of protons and neutrons.

Question 20

Triglycerides

Answer 20

A lipid formed from one molecule of glycerol and three molecules of fatty acids that may be either solid (fats) or liquid (oils) at room temperature; the body’s most highly concentrated source of chemical potential energy. Found mainly within adipocytes. Also called a neutral fat.

Question 21

Catabolism

Answer 21

Chemical reactions that break down complex organic compounds into simple ones, with the net release of energy.

Question 22

PH scale

Answer 22

A measure of the concentration of hydrogen ions (H_) in a solution. Extends from 0 to 14, with a value of 7 expressing neutrality, values lower than 7 expressing increasing acidity, and values higher than 7 expressing increasing alkalinity.

Question 23

Proteins

Answer 23

An organic compound consisting of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur and phosphorus; synthesized on ribosomes and made up of amino acids linked by peptide bonds.

Question 24

Monounsaturated fats

Answer 24

A fatty acid that contains one double covalent bond between its carbon atoms; it is not completely saturated with hydrogen atoms. Plentiful in triglycerides of olive and peanut oils.

Question 25

lipid

Answer 25

An organic compound composed of carbon, hydrogen, and oxygen that is usually insoluble in water, but soluble in alcohol, ether, and chloroform.

Question 26

fatty acid

Answer 26

simple lipid that consists of a carboxyl group and a hydrocarbon chain; used to synthesize triglyceride and phospholipids.

Question 27

glycogen

Answer 27

A highly branched polymer of glucose containing thousands of subunits; functions as a compact store of glucose molecules in liver and muscle fibers (cells).

Question 28

Buffer systems

Answer 28

A weak acid and the salt of that acid (that functions as a weak base).Prevent drastic changes in pH by converting strong acids and bases to weak acids and bases.

Question 29

Deoxyribonucleic acid (DNA)

Answer 29

A nucleic acid constructed of nucleotides consisting of one of four bases (adenine, cytosine, guanine, or thymine), deoxyribose, and a phosphate group; encoded in the nucleotides is genetic information.

Question 30

Polyunsaturated fats

Answer 30

fatty acid that contains more than one double covalent bond between its carbon atoms; abundant in triglycerides of corn oil, safflower oil, and cottonseed oil.

Question 31

enzymes

Answer 31

A substance that accelerates chemical reactions; an organic catalyst, usually a protein.

Question 32

substrates

Answer 32

A reactant molecule upon which an enzyme acts.

Question 33

anabolism

Answer 33

Synthetic, energy-requiring reactions whereby small molecules are built up into larger ones.

Question 34

Adenosine triphosphate

Answer 34

The main energy currency in living cells; used to transfer the chemical energy needed for metabolic reactions. Consists of the purine base adenine and the five-carbon sugar ribose, to which are added, in linear array, three phosphate groups.