Module 2 Biochemistry of the cell

Question 1

emphasized that for life to
exist at all , the environment must first be suitable and that leads to water

Answer 1

Richard Henderson

Question 2

Water has four emergent properties which are stated below:

Answer 2

1. Cohesion and Adhesion of Water Molecules
2. Moderation of Temperature by Water.
3. Evaporative Cooling of Water
4. Water as the Solvent of Life

Question 3

Water molecules stay close to each other as a result of ___ and these bonds that hold the water together, is a phenomenon called ____.

contributes to the
transport of water and dissolved nutrients against gravity in plants

Answer 3

hydrogen bonding

cohesion

Question 4

the clinging of one substance to another

This ____ of water to cell walls by hydrogen bonds helps counter the downward pull of gravity.

Answer 4

adhesion

Question 5

Water moderates air temperature by

Answer 5

absorbing heat from air that is warmer and releasing the
stored heat to air that is cooler

Question 6

This property of water also helps warm the air when it is nighttime and tends to stabilize the ocean temperature

Answer 6

heat must be absorbed in order to break hydrogen bonds

heat is released when hydrogen bonds formed

Question 7

contributes to the stability of temperature in lakes and ponds

also provides a mechanism that prevents terrestrial organisms from overheating

helps keep the tissue in the leaves from becoming too warm in the sunlight

Answer 7

Evaporative cooling of water

Question 8

The solvent is then involved in the dissolving of ions which contributes to processes happening in the body such as the formation of the ___

Answer 8

hydration shell

Question 9

Biomolecules (4)

Answer 9

Nucleic Acids

Proteins

Lipids

Carbohydrates

Question 10

macromolecules that exist as polymers

They store, transmit, and help express hereditary
information.

Answer 10

Nucleic acids

Question 11

A nucleotide is composed of three parts:

Answer 11

a nitrogenous base

a five-carbon sugar

one or more phosphate groups

Question 12

In a polynucleotide, each ___ has only one ____.

The portion of the nucleotide without any phosphate groups is called a ____.

Answer 12

monomer

phosphate group

nucleoside

Question 13

two families of nitrogenous bases:

has one six-membered ring of carbon and nitrogen atoms.

larger, with a six-membered ring fused to a five-membered ring.

Answer 13

Pyrimidine

Purines

Question 14

Pyrimidine (3)

Answer 14

cytosine, thymine, and uracil

Question 15

Purines (2)

Answer 15

adenine, and guanine

Question 16

found in both DNA and RNA (3)

____ is only found in DNA and ____ only in RNA

Answer 16

Adenine
Guanine
Cytosine

Thymine
Uracil

Question 17

Pairings

Adenine =

Guanine =

Answer 17

Thymine, Uracil

Cytosine

Question 18

The two ____ run in arrangement called “antiparallel”

Answer 18

sugar phosphate backbones

Question 19

a biologically functional molecule that consists of one or more polypeptides (polymers of amino acids)

Answer 19

protein

Question 20

Shapes of protein (2)

Answer 20

Globular Proteins

Fibrous Proteins

Question 21

Folding of proteins are done by ____

Answer 21

chaperonins

Question 22

when proteins are transferred from an aqueous environment to a ____, it unravels and loses its native shape by a process called denaturation.

Answer 22

non-polar solvent

Question 23

It is a linked series of amino acids with a unique sequence

Structure from inherited genetic information.

Answer 23

Primary Structure

Question 24

This is collectively referred to as ____ which are the result of hydrogen bonds between the repeating constituents of the polypeptide backbone

Answer 24

coils and folds

Question 25

Secondary structure: a delicate coil held together by hydrogen bonding between every fourth amino acid. two or more strands of the polyopeptide chain lying side by side (called b strands) are connected by hydrogen bonds between parts of the two parallel polypeptide backbones.

Answer 25

a- helix b pleated sheet

Question 26

It is the overall shape of a polypeptide resulting from interactions between the side chains (R groups) of the various amino acids.

Answer 26

Tertiary structure:

Question 27

Tertiary structure interactions: caused by the exclusion of nonpolar substances by the water molecules

Answer 27

Hydrophobic interaction

Question 28

Tertiary structure interactions: Hydrogen and ionic bonds: Hydrogen bonds are between ___ and ionic bonds are between ___

Answer 28

polar side chains positively and negatively charged side chains

Question 29

Tertiary structure interactions: These further reinforce the shape of a protein. ___ bridges are formed when two ____ have ____on their side chains which are brought closer together by the folding of protein.

Answer 29

Disulfide cysteine monomers sulfhydryl groups (-SH)

Question 30

It is the overall protein structure that results from the aggregation of these polypeptide subunits, the a and b subunits.

Answer 30

Quaternary structure

Question 31

Proteins function as: (8)

Answer 31

enzymes storage of amino acids coordinator of an organism’s activities motor proteins for movement protection against disease transport of substances response of cell to a chemical stimuli support

Question 32

Proteins function as: enzymes , selectively accelerating chemical reactions, such as ___ on hydrolyzing bonds inn food molecules. storage of amino acids, such as the ____, protein of egg white serve as storage of amino acid for the developing embryo. coordinator of an organism’s activities such as ____regulating blood sugar concentration. motor proteins for movement such as ____ for the contraction of muscles. protection against disease such as ____ inactivating bacteria and viruses. transport of substances, such as ____ transporting oxygen. response of cell to a chemical stimuli support such as ____ providing a fibrous framework in connective tissues.

Answer 32

digestive enzymes ovalbumin insulin actin and myosin antibodies hemoglobin collagen and elastin

Question 33

one class of biomolecules that does not include true polymers, and they are generally not big enough to be considered as macromolecules. major function is energy storage also cushion such vital organs as the kidneys

Answer 33

Lipids

Question 34

three types of lipids

Answer 34

fats phospholipids steroids.

Question 35

A fat is constructed from two kinds of smaller molecules:

Answer 35

glycerol and fatty acids

Question 36

___ is an alcohol; each of its three carbons bear a hydroxyl group ____ has a long carbon skeleton, having a carbon at one end which is a part of the carboxyl group.

Answer 36

Glycerol A fatty acid

Question 37

Fatty acids are hydrophobic(away from water) due to the nonpolar ____.

Answer 37

C-H bonds

Question 38

: These are formed if there are no double bonds between carbon atoms composing a chain, then as many hydrogen atoms as possible are bonded to the carbon skeleton. They lack double bonds, and their flexibility allows the fat molecules to pack together tightly.

Answer 38

Saturated fatty acid

Question 39

It has one or more double bonds , with one fewer hydrogen atom on each double-bonded carbon. Its double bonds are cis which has kinks to prevent the molecules from packing together closely enough to solidify at room temperature

Answer 39

Unsaturated fatty acid

Question 40

Cells could not exist without ____, since they are essential on making up the cell membranes function as a boundary between the cell and its external environment

Answer 40

phospholipids

Question 41

A phospholipid is similar to a fat molecule but

Answer 41

has only two fatty acids attached to glycerol rather than three

Question 42

Parts of phospholipids (2)

Answer 42

Hydrocarbon tails (hydrophobic) Hydrophilic head (affinity of water)

Question 43

When phospholipids are added to water, they self-assemble into double-layered structures called ___

Answer 43

bilayers

Question 44

These are lipids characterized by a carbon skeleton consisting of four fused rings

Answer 44

Steroids

Question 45

a crucial molecule in animals since it is a component of animal cell membranes and is also the precursor from which other steroids are synthesized, such as the sex hormones

Answer 45

Cholesterol

Question 46

Carbohydrates include both sugars and polymers of sugars. Simplest forms of Carbohydrates Consists of two monosaccharides joined by a covalent bond Polymers composed of many sugar building blocks

Answer 46

monosaccharides, or simple sugars Disaccharides polysaccharides

Question 47

Monosaccharides are simple sugars which generally have formulas that are some multiple of the unit ____ the most common monosaccharide ____, is of central importance in the chemistry of life Monosaccharides, are major nutrients for cells

Answer 47

CH2O Glucose (C6H12O6)

Question 48

Disaccharides consist of two monosaccharides joined by a glycosidic linkage, a covalent bond formed by a ____. Common types of disaccharides in food (2) Plants also transports cards from leaves to roots as ___

Answer 48

dehydration reaction Maltose, Lactose Sucrose

Question 49

Polysaccharides are macromolecules, polymers with a few thousand monosaccharides joined by linkages. Some polysaccharides serve a storage material, ____ as needed to provide sugar for cells, or even used as a building material. Plants store ___, a polymer of glucose monomers, within the _____. enabling the plant to stockpile surplus glucose, and represents as a stored energy. While animals store____mainly in liver and this is released when the demand for sugar is high, serving as a fuel. organisms build strong materials from it such as the ____ which is the major component of the tough walls that enclose plant cells Another structural polysaccharide is ____ where it is used by arthropods for their exoskeleton (hard case protecting the soft parts of the body).

Answer 49

hydrolyzed starch plastids glycogen cellulose chitin