lecture 3b&4

Question 1

what is the t test used for*

Answer 1

to test for the significant difference between the means of two groups

Question 2

when do you use the unpaired t test*

Answer 2

when comparing independent samples (from different individuals)

Question 3

when do you not use the unpaired t test*

Answer 3

data comes from the same individual before and after
less or more than two groups
no averages

Question 4

11 steps for t test*

Answer 4

1. state the null and alternate hypotheses
2. list the data of the control and experimental groups
3. record the number of replicates for each group
4. calculate the mean of each group
5. calculate the variance of each group
6. calculate the standard deviation
7. calculate the t value
8. choose a significant value (0.05)
9. figure out if you should do a one tailed or two tailed test
10. find the critical t value using the table
11. compare both t values

Question 5

what are degrees of freedom*

Answer 5

number of categories or classes minus 1
opportunity for change

Question 6

what is the formula for df*

Answer 6

df = (n1 - 1) + (n2 - 1)

Question 7

what type of hypothesis is one tailed*

Answer 7

directional

Question 8

what type of hypothesis is a two tailed hypothesis*

Answer 8

non directional

Question 9

all living things contain

Answer 9

carbohydrates, lipids, proteins and nucleic acids

Question 10

organic compounds contain

Answer 10

carbon (carbon backbone)

Question 11

properties of an organic molecule depend on

Answer 11

arrangement of the carbon skeleton (straight, branched, rings with long or short bonds)
functional groups (give molecule distinct chemical properties)

Question 12

single unit of molecules

Answer 12

monomer

Question 13

chain of monomers

Answer 13

polymer

Question 14

how do you build polymers

Answer 14

dehydration synthesis where water is released which forms a new bond

Question 15

what is hydrolysis

Answer 15

when water is added and a bond is broken in the polymer chain

Question 16

what is a carbohydrate

Answer 16

sugar

Question 17

how are carbohydrates stored in humans

Answer 17

glycogen

Question 18

how are carbohydrates stored in plants

Answer 18

starch

Question 19

what are carbohydrates used for

Answer 19

broken down for cellular respiration
short term energy reserves in muscles
structure (cellulose)

Question 20

carbs are found in which ratio

Answer 20

CH^2O= 1:2:1

Question 21

monomers are which type of carbs

Answer 21

simple sugar

Question 22

polymers are which type of carb

Answer 22

complex sugars

Question 23

what is a monosaccharide

Answer 23

monomer of carbohydrates

Question 24

types of monosaccharides

Answer 24

glucose, galactose, fructose

Question 25

what are disaccharides

Answer 25

two linked monosaccharides

Question 26

what is sucrose

Answer 26

glucose plus fructose

Question 27

glucose plus galactose

Answer 27

lactose

Question 28

glucose plus glucose

Answer 28

maltose

Question 29

what are polysaccharides

Answer 29

polymers of monosaccharides

Question 30

types of polysaccharides

Answer 30

storage and structural carbohydrates (starch, glycogen & cellulose, chitin)

Question 31

what is the main feature of lipids

Answer 31

they are hydrophobic

Question 32

function of neutral fats

Answer 32

long term energy reserve in fat tissue maintain body temperature through insulation protect vital organs buoyancy

Question 33

structure of neutral fats

Answer 33

1 molecule of glycerol 1-3 molecules of fatty acids

Question 34

3 molecules of fatty acids is called

Answer 34

triglyceride

Question 35

what is the difference between saturated and unsaturated fatty acids

Answer 35

saturated fatty acids have no double bonds between the carbon atoms while unsaturated fatty acids do have double bonds saturated fatty acids are then easier to stack since there is no bend in the chain

Question 36

differences between cis unsaturated and trans unsaturated fatty acids

Answer 36

more bend for cis

Question 37

function of phospholipids

Answer 37

major constituent of cell membranes

Question 38

structure of phospholipids

Answer 38

2 molecules of fatty acids 1 glycerol molecule 1 phosphate molecule

Question 39

what is an amphipathic molecule

Answer 39

a molecule that has a side which is hydrophilic and a side that is hydrophobic (phospholipid)

Question 40

which part of the phospholipid is attracted/repelled by water

Answer 40

the head is attracted to water (hydrophilic) the tail is repelled by water (hydrophobic)

Question 41

how does the phospholipid assemble

Answer 41

into a double layer that has the hydrophobic portions facing each other

Question 42

what are the functions of steroids

Answer 42

cell membrane (cholesterol) vitamins hormones

Question 43

structure of steroids

Answer 43

made from sterol (multiple rings of carbon)

Question 44

what do proteins do

Answer 44

pretty much everything (transport, enzymes, antibodies,storage, etc)

Question 45

proteins are made from

Answer 45

amino acids

Question 46

what is a polypeptide

Answer 46

a polymer of amino acids

Question 47

structure of amino acid

Answer 47

2 functional groups (amino and carboxyl) 1 variable group (R) a hydrogen all around a carbon

Question 48

how do you link amino acids to make a polypeptide and where

Answer 48

dehydration synthesis/condensation reaction link at the n-terminus and the c-terminus (amino and carboxyl ends)

Question 49

is the polypeptide polar

Answer 49

yes

Question 50

why is the shape of a protein important

Answer 50

the shape of the protein determines its function

Question 51

how many levels of structure are there in proteins

Answer 51

1. primary 2. secondary 3. tertiary 4. quaternary

Question 52

what is the primary structure of proteins

Answer 52

the specific and unique sequence of amino acids that make up a polypeptide

Question 53

how is the unique sequence of a.a. determined in the primary structure

Answer 53

by the nucleotide sequence of the gene that encodes the protein (genetically determined)

Question 54

what happens to the protein if an amino acid get switched

Answer 54

it will change the form of the protein which will affect how it performs its function

Question 55

what is the secondary structure of proteins

Answer 55

the folding and coiling of a sequence of amino acids within a polypeptide

Question 56

what causes the folding/coiling of proteins

Answer 56

hydrogen bonds between the amino and carboxyl groups in the polypeptide's backbone

Question 57

what is an alpha helix and where do the h-bonds occur

Answer 57

coil bond occurs every fourth amino acid

Question 58

alpha helix characteristics

Answer 58

common in fibrous proteins (hair, skin, nails) h-bonds are strong when there are many bonds (weak individually) able to stretch

Question 59

what is a beta pleaded sheet and where do h-bonds occur

Answer 59

pleated sheet of polypeptide lying parallel h-bonds between amino and carboxyl group

Question 60

beta pleaded sheet characteristics

Answer 60

make up core of globular proteins and some fibrous proteins like fibroin (spider silk) strong and flexible but not elastic can twist

Question 61

how is the distance between pleats decided in beta p.s.

Answer 61

the strong covalent bonds of the polypeptide backbone

Question 62

what is the tertiary structure of a protein

Answer 62

the forces holding a singular polypeptide together

Question 63

what determines the the 3D structure of a single polypeptide

Answer 63

1. hydrogen bonds 2. ionic bonds 3. hydrophobic interactions 4. covalent/disulphide bonds

Question 64

what are ionic bonds

Answer 64

results from ions/ plus minus charged particles

Question 65

what are hydrophobic interactions

Answer 65

hydrophobic molecules interacting with each other

Question 66

what is a disulphide bond

Answer 66

bond between sulphide groups on amino acids (covalent bond)

Question 67

what is the quaternary structure

Answer 67

the fusion of two or more polypeptide

Question 68

how is the quaternary structure formed

Answer 68

by the interactions among polypeptide chains has the same types of bonds as the tertiary structure

Question 69

what is a monomeric protein

Answer 69

protein made of a singular polypeptide chain (no quaternary structure)

Question 70

what is an oligomeric protein

Answer 70

protein made of two or more polypeptide chains

Question 71

what is denaturation

Answer 71

when a protein breaks down by unravelling or changing shape (permanent or temporary)

Question 72

what happens during denaturation

Answer 72

disruption or destruction of secondary and tertiary structures disrupts alpha h. and beta p.s so becomes a random shape primary sequence remains due to the reaction not being strong enough to break the peptide bonds (except at very high temp.)

Question 73

what can cause denaturation

Answer 73

heat and alcohol

Question 74

ribosomes characteristics (3)

Answer 74

displays quaternary structure uses RNA to make other proteins made in nucleolus