2.1.2 Flashcards
What type of molecule is water?
polar
How do hydrogen bonds form in water?
- when a slightly negative oxygen atom of 1 molecule
- is close to a
- slightly positive hydrogen atom in another molecule
What are the properties of water?
-Unusually high bp
Why does water have an unusally high boiling point?
requires lots of energy to break the many hydrogen bonds
Why is it good that water has a high boiling point?
stable water temperature
for aquatic animals
less energy spent on temp control
How is ice an important property of water?
creates an insulating barrier
water below doesn’t freeze
allowing organisms below to move under water
What is an example of ice being used in nature?
habitat for animals like polar bears on top of ice
fish can move under water
What is cohesion?
hydrogen bonding in water
What is an example of cohesion in nature?
water moving through xylem
creates high surface tension for insects like the water skater to walk on
What is adhesion?
water attraction to other molecules
or surfaces
What is an example of adhesion?
water moving through the xylem
Why is it good that water is a solvent?
allows mineral ions to be transported around plants and animals
What is an example of solvents in nature?
substances being dissolved in the blood stream?
Why is it good that water is a transport medium?
allows the transport of soluble substances
What is an example of water being a transport medium in nature?
transporting substances around the body in blood
around a plant
Why is it good that water is a cooling mechanism?
Evaporation of water takes heat away from body
What is an example of water being a cooling mechanism in nature?
sweating in mammals
panting in dogs to cool them down
Why is water having a high specific heat capacity good?
creates a stable temperature
enzymes can work at optimum temp
gases remain soluble
aquatic oraganisms
What is an example of high specific heat capacity in nature?
metabolic reactions
Why is water having capillary action good?
allows water to move up narrow vessels
What is an example of capillary action in nature?
water moves up xylem in plants
end of a
Start of b
What is a condensation reaction?
when a water molecule is removed to form a covalent bond
What is a hydrolysis reaction?
when a water molecule is added to break a covalent bond
C H O
Carbohydrates / lipids
C H O N S
proteins
C H O N P
nucleic acids
end of b
start of c
What are monosaccharides?
simple sugars that form monomer units
What are dusaccharides?
2 monosaccharides joined together
What are polysaccharides?
polymers made of a long chain of monosaccharides
What is starch?
energy store in plants
long chain of alpha glucose monomers
What is the difference between alpha and beta glucose ?
OH is at the bottom in alpha glucose
OH is at the top in beta glucose
What is a hexose sugar?
a monosaccharide with 6 carbons
What is glucose?
hexose sugar
reducing sugar
What is a reducing sugar?
in solution it reduces other chemicals
What is ribose?
pentose sugar found in RNA
How is a disaccharide formed?
2 monosaccharides
condensation reaction
How is a monosaacharide formed from a disaccharide?
hydrolysis with a water molecule
What is the bond formed between the 2 sugars in a disaccharide?
glycosidic
How is maltose made?
alpha glucose and alpha glucose
How is lactose made?
beta glucose and galactose
How is sucrose made?
alpha glucose and fructose
end of c
start of d
What is starch made of?
amylose and amylopectin
What is glycogen in animals made of?
alpha glucose subunits
Why do starch and glycogen not affect the water potential?
both dont dissolve
Why at bonds are in amylose?
1,4 alpha glycosidic bonds
What structure is amylose?
coiled
What are the properties of amylose?
compact as it is coiled-> storage
doesnt affect osmotic potential
What bonds are in amylopectin?
alpha 1,4 glycosidic
alpha 1,6 glycosidic bonds
Is amylopectin branched?
yes
What does branching allow amylopectin to do?
allows hydrolysis of ends by enzymes
to create monosaccharides that are available for areobic respiration
What bonds are in glycogen?
alpha 1,4 glycosidic bonds
alpha 1,6 glycosidic bonds
Is glycogen branches?
yes
What are the properties of glycogen?
compact - storage molecule
wont affect osmotic potential
branches - hydrolyses ends to create monosaccharides for aerobic respiration
Where are starch and glycogen found?
Starch - plants
Glycogen - mammalian livers
What is cellulose made from?
beta glucose
What does beta glucose do in cellulose?
every alternate beta glucose oreintates utself 180 degrees
What bonding is in cellulose?
1,4 glycosidic bonds
What are properties of cellulose?
high tensile strength
as there are crosslinks between microfibrils
no osmotic potential
inert
What are the groups in the general amino acid structure?
amine group
R group
R-COOH group
What is a dipeptide?
2 amino acids joined together
What is the bond ina dipeptide called?
peptide bond
What happens in the reaction converting amino acids into a dipeptide?
water is removed
What is the primary structure?
sequence of amino acids bonded by peptide bonds
What is the secondary structure?
folding of the polypeptide chain
held in place with hydrogen bonds
alpha helix or beta pleated sheets
What is the thertiary structure?
further folding in of the polypeptide chain
held by hydrogen bonds
disulphide brides
ionic bonds
amino acids with hydrophobic R groups oreintate towards centre
hydrophillic R groups oreintate outwards of the protein
What is the quaternary structure?
more than 1 polypetide chain
start of n
What are fibrous proteins?
strong proteins that have structural roles
keratin
What is keratin?
found in hair, nails
lots of disulphide bridges for strength
How does disulphide bridges affect keratin strength?
the more disulphide bridges the stronger the keratin
What are properties of fibrous proteins>?
insoluble
very strong and tough
Why are fibrous proteins insoluble?
lots of amino acids with hydrophobic R groups
Why are fibrous proteins strong and tough?
many cross bridges between polypeptide chains
What is elastin?
found in alveoli
recoils after being deformed
What is collagen?
Found in skin
flexible but doesnt stretch
Whata re globular proteins?
proteins that provide a metabolic role
What are properties of globular proteins?
compact
soluble in water
conjugates have a prosthetic group
How are globular proteins soluble in water?
amino acids with hydrophobic R groups in the centre of the protein
What are examples of globular proteins?
Insulin
Haemoglobin
Catalase
Which 2 globular proteins have a specific fixed shape?
insulin and catalse
Which 2 proteins are conjugated proteins?
haemoglobin and catalase
Ca2+
muscle contraction
synapses
Bohr effect
Na+
nerve impulses
selective reabsorption
K+
nerve impulses
H+
transolaction
chemiosmosis
photosynthesis
repiration
coenzymes
NH4+
nitrogen cycle
NO3-
nitrogen cycle
HCO3-
Bohr effect
Cl-
Bohr effect
PO43-
DNA, RNA , Phospholipids, ATP
OH-
photosynthesis
What is the buiret test?
proteins
present - lilac colour
How do you do the ebenedict test for reducing sugars?
heat sample with benedicts
reducing sugars give a
yellow
green
orange
brick red colour appears
What are some reducing sugars?
glucose
lactose
galactose
fructose
What is the benedicts test for non-reducing sugars?
heat sample with beendicts
no change heat with acid
add excess NaOH
heat sample with beendicts
Non-reducing sugar preset if yellow , green , orange brick red colour appear
What is an example of non-reducing sugar?
sucrose
What is the iodine test for starch?
brown to blue/black
What is the emulsion test for lipiuds?
add a few drops of ethanol
shake
pour over water
if lipids are present you will get a white emulsion
What do you do with the colours from the beendicts tesrt?
filter out the precipitate
calibrate the colorimeter by setting it to 0, using ablank
use a red filter and measure the absorbance
plot a calibration curve
use the calibration curve to find the concentration of the unkown glucose concentration
Why should you use gloves when handling the TLC?
so amino acids on hands dont contaminate the results
Why must the line in TLC be drawn in pencil?
pen would dissolve
Why must the solvent be below the pencil line?
amino acid would dissolve into the solvent
Why do lighter amino acids with smaller R groups travel up the chromatogram?
less resistance
What do you spray on TLC to seen amino acids?
ninhydrin
What is a triglyceride made up of?
1 glycerol
3 fatty acids
Where are the ester bonds in the triglyceride?
between the fatty acids and the glycerol
How many OH in glycerol?
3
What reaction occurs between glycerol and a fatty acids?
condensation reaction forms ester bond and 3 molecules of water
What is the difference between saturated and unsaturated fatty acids?
no double bonds in saturaated fatty acid
double bonds in unsaturared fatty acid
What is different about an unsaturated fatty acids density compared to a saturated triglyceride?
unsaturated cannot lie as close to another unsaturated triglyceride therefore it creates less dense substances like oil
What is the structure of a phospholipid?
1 glycerol
2 fatty acids
1 phosphate
How is the phosphate group able to be water soluble?
polar and hydrophillic
How is the fatty acids able to be non-polr and insoluble in water?
hydrophobic and non-polar
What are functions of triglycerides?
respiratory substrate
make hormones
waterproofing
buoyancy
forming layers of insulation
protective layers around organs, myelin sheath
aids fat absorption
Why are triglycerides good at storing energy?
they are sued as respiratory substartes and release water when broken down
Why will triglycerides not affect water potential?
insoluble
What is the structure of cholesterol?
4 carbon ring structure
What is the hydrophillic section of cholesterol?
OH group
What forms the hydrophobic section of cholesterol?
C H
What is the function of cholesterol?
regulate fluidity
How does cholesterol make membrane more rigid?
small size
and flattened shape
allows them to fit between phospholipids and bind their hydrophobic tails
making membrane more rigid
What does cholesterol do at low and high temperatures?
low - cholesterol increases fluidity
high - decreases fluidity
