Biological Molecules Ch 1, 2 Flashcards
Molecule
A group of two or more atoms linked together by a chemical bond
Element
Composed of atoms that have the same atomic number
Compound
A substance consisting of atoms or ions from different elements joined by chemical bonds into a molecules
Monomers
Smaller units from which large molecules are made
Polymer
Molecules made from a large number of monomers joined together
What is the process called when Monomer becomes polymer
Condensation, water is made
What is the process called when a Polymer becomes monomers
Hydrolysis, water is needed
What are some properties of water
Polar so can dissolve charges ions and acts as a universal solvent.
High specific heat capacity-buffers changes in temperature, reduces fluxuations
High latent heat of evaporation-cooling effect with little loss of water through evaporation.
Strong cohesion-allows surface tension and prevents columns of water breaking
Ice= lower density- habitat and layer of insulation
Metabolite- condensation and hydrolysis
What are the three monosaccharides
Glucose, fructose and galactose
What monomers make up Maltose
Glucose and glucose
What monomers make up Sucrose
Glucose and fructose
What monomers make up Lactose
Galactose and glucose
How can you tell if it’s alpha or beta glucose
Alpha- The first carbon will have H on the top and OH on the bottom
Beta- the first carbon will have a OH on top and the H on the bottom
what does alpha glucose+ alpha glucose make
maltose, starch, glycogen
what does beta glucose and beta glucose make
cellulose
what has to happen to the molecule for cellulose to be made
every other beta molecule needs to be flipped
when two glucose monomers join, what’s the name of the bond
glycosidic bond
whats the name of the bond when two proteins bond
peptide bond
whats the name of the bond when two lipids bond
ester bond
is starch branches or unbranched?
can be both, branches=amylose
unbranched=amylopectin
how is starches structure related to its function
insoluble= does not draw in water through osmosis
big= can’t diffuse out of cell
compact= can be stored in small places and more can be stored
hydrolyses=glucose for respiration
is hydrolysis faster in branches or unbranched molecules
branched because more surface contact for enzymes to work simultaneously.
is glycogen branched or not branched?
highly branched
how does glycogens structure relate to its function
insoluble=doesn’t draw in water from osmosis
big= can’t diffuse out of cells
compact= small storage space
highly branched= hydrolysis of glucose for respiration quicker
what is celluloses structure
straight unbranched chains running parallel with hydrogen bonds between chains
how is cellulose’s structure related to it’s function
hydrogen bonds allow for microfibrils that make it strong, so it can withstand turgidity/pressure
what reagent is used to test carbohydrates.
Benedict and iodine
which sugars are reducing sugars?
all monosaccharides, and maltose and lactose.
which sugars are non-reducing?
all polysaccharides, sucrose
how do you test for reducing sugars
add Benedict solution to food sample.
hot water bath
What results could you see using Benedict solution
no colour change= negative green-lowest concentration yellow brown red-highest concentration
how would you test for non-reducing sugar
(can do after testing for reducing sugars) add HCl to hydrolyse hot water bath add NaHCO3 (alkali) to neutralise acid add benedict solution hot water bath
in benedict test why does it turn red if positive for reducing sugars?
red copper oxide precipitate is made
if starch is present what colour will iodine turn?
blue to black
what is the name for the test for lipids
emulsion test
describe the emulsion test
add ethanol THEN add water
cloudy-white precipitation means lipid is present
what are some properties of lipids
insoluble in water but soluble in organic solvents
solid at room temp is saturated, liquid if unsaturated
proportion of oxygen and hydrogen is smaller than carbohydrates
what are the functions of lipids
cell membrane source of energy (produced 2x the energy as the same mass of carbohydrates) source of water when oxidised waterproofing insulation protection hormones
name two types of lipids
triglycerides and phospholipids
what makes up a triglyceride
glycerol and 3 fatty acid
what makes up a phospholipid
hydrophilic phosphate, glycerol and two hydrophobic fatty acids
why is phospholipids used in the cell membrane
because it creates a phospholipid bilayer due to its hydrophobic and hydrophilic properties
Give functions for Protein
Enzyme, hormones, antibodies, blood clotting, toxins, antifreeze, receptors
what elements make up protein
C,H,O,N
What is a amino acid molecule made up of
anime group (NH2) and carboxyl group (COOH) and R group
what is the name of the molecule when two amino acids bond
dipeptide
What is Primary Structure
Many amino acids joined together, the sequence determined by the DNA
What is Secondary Structure
Weak hydrogen bonds cause polypeptide chains to twist into 3D shape.
What are the two secondary Structure shapes
a-helix or beta pleated sheet
What is tertiary Structure
From the secondary structure, the chain twists and folds to make a more complex and specific shape.
What bonds are in involved in the tertiary structure, strongest to weakest
Disulfide bond, ionic bond, hydrogen bond and hydrophobic interactions.
What is the Quaternary Structure
When more than one polypeptide chains are linked together, or the have non-protein attached. E.G haemoglobin has iron.
Describe the test for Protein
Biuret test- Add NaOH to protein.
Add drop by drop CuSO4, shaking in between
Lilac=positive
What is a semi-quantitative test?
When is shows the amount/concentration present as well as if it is present.
Name a semi- quantitative test
Benedict Test
Other than looking at the colour of the solution after a Benedict Test, how can you determine the conc present?
Filter the solution, dry and then weigh .
Why is water being an universal solvent important to living organisms?
Used for transport of substances through the blood and phloem.
Why is water having a high latent heat of vaporisation important to living organisms?
Used for cooling (sweating)
Why is water having a specific heat capacity
important to living organisms?
Prevents large temperature fluctuations
Why is water being less dense as ice than as liquid important to living organisms?
Insulating layer under the sea allowing organisms to live
Why is water being transparent important to organisms?
Allows photosynthesis in organisms living in the water
What is the monomer of DNA?
Nucleotide (Nucleic Acid)
What is the monomer of RNA?
Nucleotide (Nucleic Acid)
What is the structure of a Nucleotide in DNA?
(Deoxyribose) Pentose sugar, Nitrogen Base, phosphate
What is the structure of a Nucleotide in RNA?
(ribose) Pentose sugar, Nitrogen Base, phosphate
What are the four bases in DNA?
Adenine, Thymine, Guanine, Cytosine
What are the four bases in RNA?
Adenine, Uracil, Guanine, Cytosine
What is the back bone of the DNA?
Phosphate and deoxyribose (pentose sugar) form a phosphodiester bond
What bonds are between the bases?
Hydrogen bonds
Why is DNA stable?
The phosphodiester backbone protects the more chemically reactive bases. H bonds between bases
What bases are purine?
Adenine, Guanine
What bases are pyrimidines?
Cytosine, Thymine, Uracil
What is a hypothesis?
A suggested explanation of something based on some logical scientific idea.
What type of DNA replication do mammals have?
Semi-conservative
Describe the process of DNA replication
- DNA helicase breaks H bonds so double helix unwinds.
- Each strand acts as a template and complimentary free nucleotides bases bind.
- DNA polymerase forms phosphodiester bonds
What experiment can you do to prove DNA replicates in a Semi-conservative way?
Use Nitrogen14 and the isotope N15. Combine a 14N DNA and a 15N DNA to produce a DNA that has 15N and 14N. Dupicate another DNA using 14N again to produce two DNA strands one 14N and 15N which will be denser than the 14N14N.
Where does all energy initially come from?
The sun
What’s the structure of ATP
Adenine, Ribose and phosphates (three in a chain)
What is ATP used as?
A source of energy
Why is ATP a good source of energy?
The bonds between phosphate have a low activation energy and are unstable. Therefore they are easily broken and when they do break they release a considerable amount of energy. ATP allows energy to be released in manageable quantities.
What reaction does ATP go under to produce ADP?
Hydrolysis reaction
In what three ways can ATP be made from ADP?
photo phosphorylation (ETC) , oxidative phosphorylation (ETC), substrate-level phosphorylation (Phosphate from other molecules join)
GIve some uses of ATP?
Metabolic process- provides energy to build molecules (macromolecules)
Movement- muscle contractions.
Active Transport
Form lysosomes
Can phosphorylate other molecules to make more reactive (eg. adding phosphate to glucose).
Why does DNA polymerase sometimes work in opposite directions during DNA replication?
DNA has antiparallel stands so the nucleotides are aligned differently. Enzymes have active sites with specific shape and only the 3’ end can bin with the active site of polymerase.
What is Hydrophilic?
Will dissolve with water
What is hydrophobic
Will not dissolve with water
Why is there a greater range in temperature on land than in water?
Water has a higher specific heat capacity than air so more heat is needed to raise the temperature of water/
Why is it necessary to synthesis large amounts of ATP?
ATP cannot be stored and only releases a small amount of energy at a time
Why is ATP a suitable source of energy in biological processes?
Soluble, energy is released in small amounts, and releases energy in a simple reaction.
