Unit 02: Chemical Components of Cells

Question 1

What can be considered an aqueous solution? Name some examples in the human body.

Answer 1

Any solution where solutes are dissolved in liquid water.

cytosol and area around cells are examples

Question 2

define organic chemistry.

Answer 2

the study of carbon compounds

Question 3

define an element.

Answer 3

a substance that cannot be broken down or converted via normal chemical means

Question 4

where are protons and neutrons found in an atom?

Answer 4

nucleus

Question 5

what makes an isotope radioactive?

Answer 5

when there are disproportionately more neutrons than protons

Question 6

where are electrons found in an atom?

Answer 6

orbiting around nucleus

Question 7

what are isotopes? give an example.

Answer 7

atoms containing same number of protons but differing number of neutrons.

ex. carbon can have 6, 7 or 8 neutrons, giving us C12, C13, C14

Question 8

which isotopes of carbon are stable

Answer 8

C12, C13

Question 9

which isotopes of carbon are radioactive

Answer 9

C14

Question 10

which elements are most important to sustain life

Answer 10

c, h, o, n

Question 11

which elements are the second most important to sustain life

Answer 11

na, mg, k, ca, p, s, cl

Question 12

what are the trace elements?

Answer 12

f, se, i, zn, cu, mo, ni, co, fe, mn, cr, v

Question 13

rank the different bonds from strongest to weakest.

Answer 13

covalent, ionic, hydrogen, van der waals forces

Question 14

what is bond length? why is it specific for each bond?

Answer 14

the distance between two nuclei in a bond.

differ because too far there is no interaction, too close, they repel, so length must be just right

Question 15

define a molecule.

Answer 15

cluster of atoms held together by covalent bonds

Question 16

what is bonding capacity?

Answer 16

the amount of covalent bonds an atom can make.

Question 17

what is the bonding capacity of oxygen?

Answer 17

2

Question 18

how do enzymes speed up reactions?

Answer 18

by carefully controlling the breaking and forming of covalent bonds

Question 19

what makes a structure polar?

Answer 19

when one atom has a slight positive charge and another has a slight negative charge

Question 20

how many times weaker are ionic bonds than covalent bonds?

Answer 20

10-100x weaker

Question 21

why does water have high bp and surface tension?

Answer 21

h-bonding

Question 22

t/f, h-bonds are easily broken with random thermal motion

Answer 22

true

Question 23

what are van der waal forces?

Answer 23

attractions that result from the fluctuation in distributions of electrons as atoms approach e/o

Question 24

what are hydrophobic forces?

Answer 24

pushing of non-polar surfaces out of hydrogen bonded frame work

Question 25

why are hydrophobic forces important?

Answer 25

in forming cell membranes

Question 26

which group do weak acids usually have?

Answer 26

carboxyl groups (-COOH)

Question 27

which group do weak bases usually have?

Answer 27

amino groups (NH2)

Question 28

what are organic molecules?

Answer 28

carbon containing molecules

Question 29

what is the range of masses for small organic molecules?

Answer 29

100-1000 daltons

Question 30

what is the maximum number of carbons that a small organic molecule can contain?

Answer 30

30

Question 31

what are the 4 small organic molecules, which macromolecules do they make up?

Answer 31

sugars -> carbs fatty acids -> lipids amino acids -> proteins nucleotides -> nucleic acids

Question 32

do scientists focus on macro or macromolecules? why?

Answer 32

macro bc micro r too tiny!

Question 33

what is the general chemical formula for monosaccharides?

Answer 33

(CH2O)n

Question 34

what are isomers?

Answer 34

two compounds that have the same chemical formula but different structures

Question 35

what are optical isomers?

Answer 35

isomers that are mirror images of each other

Question 36

what is an isomer of glucose?

Answer 36

fructose

Question 37

do condensation reactions release or consume energy?

Answer 37

consume

Question 38

how do condensation rxns work?

Answer 38

H2O removed between the two monomers to force a bond.

Question 39

which disaccharide is made up of glucose and fructose?

Answer 39

sucrose

Question 40

what is an oligosaccharide?

Answer 40

carbohydrate made of 2-10 monosaccharides

Question 41

what is a glycoprotein?

Answer 41

a protein attached to an oligosaccharide

Question 42

what is a glycolipid?

Answer 42

lipid linked to oligosaccharide

Question 43

what constitutes a polysaccharide?

Answer 43

>10 monosaccharides

Question 44

what are the functions of polysaccharides? where can these functions be seen?

Answer 44

- long term storage of glucose (glycogen in animals, starch in plants) - structural molecules (cellulose - used to make cell wall of plants, chitin - used to make fungal; cell wall and exoskeleton of arthropods)

Question 45

what is the biggest and most abundant polysaccharide?

Answer 45

cellulose

Question 46

what is the difference between saturated and unsaturated fatty acids?

Answer 46

saturated - no double bonds, so as many hydrogens as possible. solid at room temp, typically animal fats unsaturated - double bonds present causing kinks in fatty acid tails, liquid at room temp, typically plant fats

Question 47

how much more energy is present in one gram of fatty acid vs. one gram of carbs? what does this tell us?

Answer 47

6x more energy. tells us that carbs give quick energy, while fatty acids provide stored energy.

Question 48

what is the definition of a lipid?

Answer 48

molecule insoluble in water but soluble in fat and organic solids

Question 49

what is a triacylglycerol?

Answer 49

3 fatty acid chains bound to a carbon each all bound to a glycerol

Question 50

what is a phospholipid?

Answer 50

2 fatty acid chains bound to a glycerol which is also bound to a phosphate which is also bound to a polar head group. third carbon is bound to the phosphate group instead of the glycerol

Question 51

what are some structural similarities for steroids?

Answer 51

- multiple circular linked aromatic rings - made of just hydrogen and carbon - same 4 aromatic rings

Question 52

what makes steroids different?

Answer 52

different functional groups bound to the aromatic rings giving them different functions

Question 53

what forms of amino acids exist. what are these to eachother?

Answer 53

D and L forms, are optical isomers

Question 54

what form of amino acid are found in proteins?

Answer 54

L forms

Question 55

what is the linkage between monosaccharides?

Answer 55

glycosidic linkages

Question 56

what is the linkage between fatty acids?

Answer 56

ester linkages

Question 57

what is the linkage between proteins?

Answer 57

peptide bonds

Question 58

what is the linkage between nucleotides?

Answer 58

phosphodiester bonds

Question 59

at what end of the polypeptide is the amino group

Answer 59

N-terminus

Question 60

at what end of the polypeptide is the carboxyl group?

Answer 60

C-terminus

Question 61

what are the pyrimidines? how many rings do they have?

Answer 61

C, T, U. 1 ring

Question 62

what are the purines? how many rings do they have?

Answer 62

A, G. 2 rings

Question 63

what is a nucleoside?

Answer 63

nucleotide without the phosphate group, so just has sugar and base.

Question 64

can RNA fold upon itself to create 3D shapes as complex as proteins?

Answer 64

yes!

Question 65

what is considered the "middleman" of the central dogma

Answer 65

RNA

Question 66

describe the structure of atp

Answer 66

3 phosphate grps bound to each other and then bound to ribose sugar which is then bound to adenine

Question 67

what does the addition of water to ATP do?

Answer 67

dephosphorylate to create ADP

Question 68

which bonds hold together phosphates?

Answer 68

phosphoanhydride bonds

Question 69

describe by which the process of hydrolysis releases free energy.

Answer 69

- negative charges are forced together to create bond which requires a lot of energy which then builds up - when a bond is broken, free energy is then released to use for other bonds

Question 70

each bond between monomers is a single _____ bond

Answer 70

covalent

Question 71

what are conformations?

Answer 71

shapes of molecules based on flexibility of bonds.

Question 72

how are conformations formed?

Answer 72

weak bonds between different parts of a molecule form, twisting the molecule into one unique, distinctive shape