Exam 1 (Ch 3 - Ch 4)

Question 1

Organic compounds

Answer 1

always contain carbon

Question 2

Which of the following statements regarding carbon is false?

Answer 2

carbon has the ability to bond with up to six other atoms

Question 3

Propanol and isopropanol are isomers. This means that they have

Answer 3

the same molecular formula, but different chemical properties.

Question 4

A hydroxyl group is a functional group consisting of an oxygen atom

Answer 4

characteristic of alcohols

Question 5

which of the following is a carboxyl group

Answer 5

―COOH

Question 6

Which of the following is an amino group

Answer 6

―NH2

Question 7

Which of the following contains a carboxyl and an amino group

Answer 7

amino acids

Question 8

The reaction that joins two monomers to form a polymer is known as a _____ reaction. The molecule of water formed is due to the interaction between _____ and a hydrogen ion.

Answer 8

dehydration … a hydroxyl group

The reaction removes a molecule of water, so it dehydrates the molecule. The interaction occurs between the hydroxyl group of one molecule and a hydrogen ion of a second molecule.

Question 9

The results of dehydration synthesis can be reversed by

Answer 9

hydrolysis

Question 10

A molecule with the formula C6H12O6 is _____.

Answer 10

possibly glucose or fructose

Fructose and glucose differ in the arrangement of their carbonyl groups and are isomers, which means that they have the same molecular formula (C6H12O6). The alteration in arrangement leads to their varied properties.

Question 11

Many names for sugars end in the suffix

Answer 11

-ose

Question 12

A disaccharide forms when

Answer 12

two monosaccharides join by dehydration synthesis.

Question 13

Cellulose differs from starch in that

Answer 13

most animals cannot break down cellulose, whereas starch is easily digested.

Question 14

Foods that are high in fiber are most likely derived from

Answer 14

plants

Question 15

Cows can derive nutrients from cellulose because

Answer 15

their intestinal tract contains cellulose-hydrolyzing microorganisms.

Question 16

The storage form of carbohydrates is ________ in animals and ________ in plants.

Answer 16

glycogen . . . starch

Question 17

An oil may be converted into a substance that is solid at room temperature by

Answer 17

adding hydrogens, decreasing the number of double bonds in the molecules.

Question 18

The oil and vinegar in your salad dressing remain separate from one another due to the _____ properties of the oil.

Answer 18

hydrophobic

Oils and other fats are water-fearing or hydrophobic and will not dissolve in water-based solutions such as vinegar.

Question 19

Fatty acids with double bonds between some of their carbons are said to be

Answer 19

unsaturated.

Question 20

A phospholipid is composed of

Answer 20

one glycerol molecule linked to one phosphate group and two fatty acids.

Question 21

Amino acids can be distinguished from one another by

Answer 21

the chemical properties of their R groups.

Question 22

Proteins differ from one another because

Answer 22

the sequence of amino acids in the polypeptide chain differs from protein to protein.

Question 23

The primary structure of a protein is

Answer 23

the amino acid sequence of the polypeptide chain.

Question 24

A hydrophobic amino acid R group would be found where in a protein?

Answer 24

on the inside of the folded chain, away from water

Hydrophobic R groups are nonpolar. By orienting within the folded chain, they avoid coming into contact with water.

Question 25

What is the process by which cells link monomers together to form polymers?

Answer 25

dehydration reaction Monomers are linked together with the removal of a water molecule by dehydration reaction.

Question 26

In a hydrolysis reaction, _____. In this process, water is _____.

Answer 26

a polymer breaks up to form monomers ... consumed The meaning of "hydrolysis" is to break with water.

Question 27

Manufacturers make vegetable oils solid or semisolid by _____.

Answer 27

adding hydrogens The phrase "hydrogenated vegetable oils" found on food labels means that unsaturated fats have been synthetically converted to saturated fats by the addition of hydrogen.

Question 28

How many different kinds of amino acids are there in most proteins?

Answer 28

20 There are 20 amino acids, all with different properties.

Question 29

To what does the term polypeptide specifically refer?

Answer 29

amino acids linked by dehydration synthesis A polypeptide is a chain of amino acids that have been linked together by dehydration synthesis to form the characteristic peptide bond.

Question 30

A scanning electron microscope is used to study ________, whereas a transmission electron microscope is used to study ________.

Answer 30

cell surfaces . . . internal cell structures

Question 31

The idea that all living things are composed of cells and that all cells come from other cells defines

Answer 31

cell theory.

Question 32

________ cells lack a membrane-enclosed nucleus.

Answer 32

Prokaryotic

Question 33

The maximum size of a cell is limited by _____.

Answer 33

its need for enough surface area to make exchanges with its environment Because volume increases at a faster rate than surface area, large cells have proportionately less plasma membrane surface area.

Question 34

A certain cell has a dense nucleoid region, ribosomes, but no membrane-enclosed organelles. Based on this information, it could be _____.

Answer 34

an archaean Archaea and other prokaryotes have no internal membrane-enclosed organelles. However, they do have both ribosomes and a region called the nucleoid region where their DNA can be found.

Question 35

Of the following organelles, which group is involved in manufacturing the substances needed by the cell?

Answer 35

ribosome, rough endoplasmic reticulum, smooth endoplasmic reticulum Each structure is capable of synthesis.

Question 36

The internal skeleton of a cell is composed of _____.

Answer 36

microtubules, intermediate filaments, and microfilaments These three types of fibers make up the cytoskeleton.

Question 37

Your intestine is lined with individual cells. No fluids leak between these cells from the gut into your body. Why?

Answer 37

The intestinal cells are bound together by tight junctions. The membranes of neighboring cells are actually fused at a tight junction, forming a seal that prevents the leakage of extracellular fluid across a layer of epithelial cells.

Question 38

The cell junctions in plant cells that provide channels between adjacent cells are generally _____.

Answer 38

plasmodesmata Plasmodesmata form channels between adjacent plant cells.

Question 39

Mitochondria appear in the greatest numbers in cells that are _____.

Answer 39

metabolically active Mitochondria are the sites of cellular respiration, the catabolic process that generates ATP by extracting energy from food molecules, with the help of oxygen.

Question 40

The rough endoplasmic reticulum is considered to be in which general functional category of organelle?

Answer 40

manufacturing The rough endoplasmic reticulum is involved in the manufacture of proteins.

Question 41

To enter or leave any cell, substances must pass through _____. View Available Hint(s)

Answer 41

the plasma membrane The plasma membrane defines the boundary of the cell.

Question 42

Plant Cell Wall

Answer 42

Strong, protective structure made from cellulose fibrils

Question 43

Central Vacuole

Answer 43

Regulates cytoplasm composition, creates internal pressure, and stores cell compounds

Question 44

Chloroplast

Answer 44

Makes food by converting light energy into chemical energy

Question 45

Mitochondrion

Answer 45

Converts chemical fuel into packets of chemical energy (ATP) that can power the cell

Question 46

Golgi Apparatus

Answer 46

Modifies and packages proteins

Question 47

Which cell structure is responsible for metabolism?

Answer 47

mitochondrion Mitochondria are involved in the process of converting the chemical energy of food to ATP.

Question 48

The function of chloroplasts is

Answer 48

photosynthesis.

Question 49

Where are chlorophyll molecules located within plant cells?

Answer 49

embedded in the thylakoid membrane Chlorophyll molecules are embedded within the thylakoid membrane, which is the most extensive membrane system within plant cells.

Question 50

What mitochondrial feature enhances cellular respiration?

Answer 50

cristae These folds increase the surface area of the membrane, allowing more proteins to be embedded and thus enhancing the ability of the mitochondrion to produce ATP.

Question 51

Which is a typical function of lysosomes?

Answer 51

breaking down of damaged organelles, such as chloroplasts Lysosomes do break down damaged organelles; lysosomes are rarely found in plant cells.

Question 52

What is the relationship between the Golgi apparatus and the plasma membrane?

Answer 52

The finished products of the Golgi apparatus may leave the cell through vesicles that fuse with the plasma membrane. Transport vesicles from the Golgi move to the plasma membrane for export. Or the finished products become part of the plasma membrane or part of another organelle.

Question 53

The two main functions of the rough endoplasmic reticulum are the production of

Answer 53

membrane and proteins secreted by the cell.