Lisa Numann - Topic 2

From KstructIB

Topic 2

2.1.1 State 3 most common elements

carbon
hydrogen
oxygen

2.1.2 State the roles of:

nitrogen: makes up proteins and nucleic acids
sulfur: makes up protein and present in certain amino acids
phosphorous: makes up phospholipids and nucleic acids
iron: makes up some proteins
potassium: moves things in and out of cells, also causes electrical charges in membranes

2.1.3 Explain atom versus ion.

atom: a building block of a molecule
ion: a charged atom

2.1.4 Define organic

organic: contains carbon

2.1.5 Draw water polarity showing hydrogen bonding

2.1.6 Outline water.

water is transparent so sunlight can get through and allow photosynthesis in underwater plants.
cohesion is the attraction of water through hydrogen bonds
surface tension is due to the hydrogen bonds making water difficult to boil and evaporate.
water is a universal solvent, everything except lipids is soluble in water.  
through sweating one uses water to cool the skin. 

2.1.7 Discuss water as a:

coolant: 
transport medium:
habitat:

2.2.1 Draw an amino acid

2.2.2 Draw ring structure of alpha D glucose

2.2.3 Draw glycerol and fatty acids

2.2.4 Outline the role of condensation versus hydrolysis

condensation: removal of water to break down a molecule
hydrolysis: addition of water to make a bigger molecule

2.2.5 Draw a dipeptide

2.2.6 Explain solubility of carbohydrates, lipids and proteins.

carbohydrates = soluble
lipids = not soluble due to non-polar fatty acid
proteins = soluble

2.2.7 Compare energy content of carbohydrates, lipids and proteins

lipids > proteins > carbohydrates

2.2.8 List two examples of a monosaccharide, disaccharide and polysaccharides

monosaccharides
glucose
fructorse
dissaccahrides
maltose
sucrose
lactose
polysaccaharides
glycogen
starch

2.2.9 State functions of monosaccharides and polysaccharides

monosaccharides: quick energy source
polysaccharides: long term energy source

2.2.10 State 3 functions of lipids

large amount of stored energy
cushion
insulation
protection

2.3.1 Define enzyme

enzyme: biological catalyst who speeds up reactions but requires specific environment to function

2.3.2 Define active site

active site: site of the enzyme where the substrate binds
can be inhibited by a competitive inhibitor

2.3.3 Describe lock and key model

enzyme’s active site fits specifically to a certain substrate

2.3.4 List 3 factors affecting enzyme activity

temperature
substrate concentration
pH

2.3.5 Outline the effects of temperature and substrate concentration on enzyme activity

substrate: enzyme reaches its maximum potential
temperature: denatures enzyme

2.3.6 Define denaturation

denaturation: when an environmental factor causes the enzyme to no longer work

2.4.1 Outline DNA structure

phosphate
sugar: deoxyribose
base: cytosine, guanine, adenine, thymine
hydrogen bonding
nucleotides
single strand
double helix

2.4.2 List five nitrogen bases and which bonds to which

cytosine bonds to guanine
adenine bonds to thymine

2.4.3 – 2.4.5 Draw DNA double helix

2.4.4 Explain in written form how a DNA double helix is formed using complementary base pairing and hydrogen bonds

2.5.1 State that DNA replication is semi-conservative.

2.5.2 Outline replication in eukaryotes

DNA B designates the intimation site
Helicase uncoils DNA
REP enzyme breaks the weak hydrogen bonds between the nucleotides bases
SSB protein holds the strands apart so they do not rebind
Primase prepares each lagging stand by adding a primer
primer is made of 10 nitrogen bases
DNA Polymerase III binds to initiation site and starts binding the free nucleotides to deoxyribose.
DNA Polymerase I removes the primer and replaces it with DNA to make it one continuous strand
Ligase patches the Okazaki fragments together.

2.6.1 Compare DNA versus RNA

base: thymine/uracil
sugar: deoxyribose/ribose
number of strands: 
DNA: 2
RNA: 1
location: 
DNA: nucleus
RNA: nucleus, ribosome, cytosol

2.6.2 State one function for each type of RNA

mRNA: passes on message
rRNA: location
tRNA: materials to make protein

2.6.3 Outline DNA transcription in terms of the formations of a RNA strand complementary to DNA strands by RNA Polymerase

RNA Polymerase places free nucleotides complementary to DNA order
thymine is replaced by uracil

2.6.4 Describe the genetic code in terms of codons composed of triplets of bases.

2.6.5 Describe translation including the roles of mRNA codons, tRNA anticodons and ribosome leading to peptide linkage formation.

codon: three bases coding for one protein
tRNA: clover-leaf shaped structure that codes for codon
ribosome: provides location for translation into A and P site.

2.6.6 Define degeneracy

degeneracy: having more than one base triplet to code for one amino acid and this allows for a universal genetic code

2.6.7 Explain the relationship between one gene and one polypeptide and its significance.

genes determines contents of a polypeptides
polypeptides: code for our body and make us what we are.