1C: Diet and Health Flashcards
what is a monosaccharide?
1 of the sub-groups of Carbohydrates
singular simple sugar molecular unit
what are carbohydrates?
molecules that only contain carbon, hydrogen, and oxygen
(also known as saccharides or sugars)
what is the importance of carbohydrates?
• they are the main energy supply in living organisms
• They are broken down to provide usable energy for these organisms - they can also store energy in the cells of the organism
what is a disaccharide?
a sugar molecule made up of two monosaccharides that have been joined together via a condensation reaction
what is a condensation reaction?
when two hydroxide groups (OH/HO) react together and water is released during the reaction.
what holds monosaccharides together?
once a condensation reaction has occurred - a covalent bond is formed called a glycosidic bond
(name may vary depending on what carbons it has linked ie 1-4 bond)
what is a polysaccharide?
carbohydrate polymers ,made up of multiple sugar units formed through condensation reactions
what are the structure of monosaccharides?
(fructose, glucose and galactose)
hexose (hexogan)
what are the monosaccharides you need to know?
• glucose
- amylose and amylopectin
• fructose
• galactose
what creates the disaccharide maltose?
glucose + glucose
what creates the disaccharide sucrose?
glucose + fructose
what makes the disaccharide lactose?
glucose + galactose
what makes the disaccharide lactose?
glucose + galactose
what is starch made up of? and what are they?
Two Glucose Polymers
• amylose - polysaccharide of glucose
• amylopectin- polysaccharide of glucose
Is starch good or storing energy? Why?
Yes
• it is compact therefore it can store more.
• it is insoluble so it doesn’t affect the water potential of the cell and will not affect osmosis.
• does not take part in cell reactions.
how many carbons does glucose have
6 carbons , 1 oxygen, 1 hydrogen, 1 hydroxide
What is Glycogen?
polymer of glucose
is glycogen good for storing energy? Why?
Yes
• it acts as an immediate energy store as it is stored in the liver- can be readily converted into glucose
• contains 1,4 & 1,6 glycosidic bonds therefore it has more branches than starch - more glucose molecules are attached to it
what are the three polysaccharides you need to know?
glycogen,amylose and amylopectin
what makes up the polysaccharides amylose and amylopectin?
chains of glucose monomers held together by 1,4 glycosidic bonds through condensation reactions
what makes up the polysaccharide glycogen?
glucose monomers held together through 1,4 and 1,6 glycosidic bonds through condensation reactions
how does insolubility enable starch to be a storage substance?
it doesn’t affect the rate of osmosis as the water potential of the cell does not change.
what is the shape of starch and why is it important?
- has a spiral shape (hexose)
- makes it more compact therefore it can hold more energy
- takes up less space
what is cellulose made up of?
Chains of beta glucose
what is glycogen made up of?
Chains of alpha glucose
what is hydrolysis?
when water is added into the reaction, with the use of enzymes, the glycosidic bond is broken and therefore breaking the polymer
what is amylose made up of?
alpha glucose molecules joined together by 1-4 glycosidic bonds
what are the benefits of a hexose structure?
more compact and less soluble than glucose
what is amylopectin made from?
alpha glucose molecules bonded with 1-4 glycosidic bonds and 1-6 glycosidic bonds
what is the structure of amylose?
unbranched hexose strand (helix)
what is the structure of amylopectin?
branched straight chain
explain how the structure of amylopectin and glycogen make then suitable for storing energy? (3)
• branched strand therefore more energy is released bc more hydrolysis takes place
• it is insoluble therefore water doesn’t go into the cell via osmosis (prevents swelling of the cell)
• has branches therefore is more compact and can hold more
• A large molecule therefore it is too big to diffuse across the membrane (minimises loss of energy)
Describe the structure of starch? (5)
• made up of amylose and amylopectin
• long chain of alpha glucose molecules
• amylose is an unbranched polymer that spirals as the chain lengthens, makingit more compact for storage
• amylopectin is a straight chain with branches that can readily release energy through hydrolysis
difference between polysaccharides glycogen and amylopectin ?
• glycogen has more beaches therefore can carry more energy
• glycogen is more compact therefore less space is needed for it to be stored
• both are insoluble
what are lipids?
molecules containing carbon,hydrogen and oxygen
what are fats?
lipids at room temperature
what are oils ?
lipids at room temperature that are liquid
why is a lipid not a polymer?
they are not built from repeating units - they are complex molecules called macromolecules
why do lipids supply twice the amount of energy as carbohydrates?
lipids contain a higher amount of hydrogen and carbon therefore more energy can be released
what are the uses of lipids?
• source of energy
• can be used for energy storage
• for biological membranes
• waterproofing
• insulation
• cushioning - to protect organs
• steroid hormones
what is a triglyceride?
one glycerol molecule joined together with three fatty acids using an ester bond
what is an ester bond?
where two hydroxide atoms bond and water is released- leftover Oxygen bonds to carbon
how is a triglycerides synthesised?
- a hydrogen atom on the glycerol molecule bonds to a hydroxyl group on the fatty acid - releasing a molecule of water (this is the condensation reaction
- the remaining oxygen atom bonds to carbon atoms (this is the ester bond)
what is the formula of glycerol ?
C3H8O3
what is a saturated triglyceride?
surrounded by hydrogen and do not have any double bonds between the carbon atoms in the hydrocarbon tails
what is a unsaturated triglycerides?
not fully surrounded by hydrogen and has double bonds between some of the carbon atoms
how to saturated triglycerides appear
a straight chain
how to unsaturated triglycerides appear?
a kinked chain
where are saturated lipids found?
animal fats
where are unsaturated lipids found?
plants
how is energy supplied to organsims
food
what is an energy budget
the amount of energy taken in by an organism and the amount of energy used up by an organism
what can energy imbalance cause
a change in weight
how can an energy imbalance cause weight gain
if energy intake is higher than energy output , excess energy is converted into fat reserves
- if the energy difference is sustained over a long time, the person may become obese
how can an energy imbalance cause weight loss
if energy intake is lower than energy output, the body takes the energy from the fat reserves within the body
- if difference is sustained the person is likely to become underweight
what is the recommended daily calorie intake for women
2000
what is the recommended daily calorie intake for men
2500
how do you calculate energy budget
energy input - output
what is needed to maintain homeostatis ( essential body processes)
a constant supply of energy
In what 4 things are Basal Matabolic Rate higher in
- males
- heavier people
- young people
- people who are active
what is a basal metabolic rate
the energy needed for essential bodily processes to take place
how do you calculate BMI
weight (kg) divided by height^2 (m)
What is your BMI if you are considered underweight
under 20
what is your BMI if you are normal in weight
20-25
what is your BMI if you are considered over weight
25-30
what is your BMI if you are considered obese
over 30
what is the ‘normal’ women waist:hip ratio
0.85
what is the ‘normal’ male waist:hip ratio
0.9
how does cholesterol affect CVD
too much can increase risk to CVD
what is cholesterol
a type of lipid made in the body
what is the function of cholesterol
to maintain the integrity of cell membranes
how does cholesterol travel through the bloodstream
it combines with lipoproteins
what is the difference between HDLs or LDLs
HDLs are mainly protein
LDLs are mainly lipids
Are HDLs saturated or unsaturated
unsaturated
are LDLs saturated or unsaturated
saturated
what is the function of HDLs
to transport cholesterol to the live and reduce total blood cholesterol levels
what is the functions of LDLs
to transport cholesterol to cells from the liver and to increase blood cholesterol levels
how do saturated fats effect diet
the increase blood cholesterol levels
how do unsaturated fats effect diet
decrease blood cholesterol levels
what are statins
drugs used to lower LDLs - this helps reduce the build up of lipoproteins in arteries
what do statins do
they lower blood cholesterol levels by inhibiting the production of it in the liver
what side effects can statins have
headcahes, pins & needles, abdominal pain, nausea, liver failure, muscle damage, memory loss, joint pain
what fats are good for the body
HDLs / unsaturated
what fats are bad for the body
LDLs / Saturated
how do saturated fats affect blood
increase blood cholesterol which increases risk of a thermos formation
what is the effect of unsaturated fats in blood
decreases blood cholesterol level which reduces risks of atheroma formation
what is cardiovascular disease
a disease where blood flow is reduced to the heart and blood vessels
what are the 10 CVD risk factors
Smoking, Salt, Exercise, Obesity, Cholesterol, Alcohol, Age, Gender, Genetics, Stress
how does smoking affect CVD
reduces the levels of HDLs in your blood stream which increases the risk of atheroma formation in arteries due to cholesterol deposition
how does salt affect CVD
increases the risk of having high blood pressure which leadings to artery lining damage and atheroma formation
how does exercise affect CVD
lack of exercise means that the heart will not work as efficiently as it should as exercise improves blood circulation and increases levels of HDLs in the body
How does obesity affect CVD
High blood pressure induced - the person has a higher body mass therefore they need a higher blood supply to supply oxygen and nutrients to their body
LDL levels increase-> increased risk of atheroma formation and atheroscolosis
how does cholesterol affect CVD
- the higher the levels of cholesterol/LDLs in the blood, the higher the risk of atheroma formation
- cholesterol is broken down in liver-> if there is too much LDL in blood, the cholesterol is not broken down and remains in blood
how does alcohol affect CVD
decreases blood flow which increases blood pressure - can also lead to obesity
how does age affect CVD
arteries become less elastic with age which can increase blood pressure and increase the risk of damaging the artery lining
how does gender affect CVD
women have a lower risk of atheroma formation bc they have a higher level of HDLs in their body bc they have higher oestrogen levels
how does genetics affects CVD
inherited alleles can increase the risk of atheroscolosis
- some genes can either increase or decrease risk
how does stress affect CVD
stress causes the release of the hormone adrenaline-> this increases heart rate and constricts arteries which increases blood pressure
how do you calculate blood pressure
force / surface area of vessel
