Biology (Diet and Food production)

Question 1

A balanced diet is one which has?

Answer 1

all nutriendts required in proportionate amounts

Question 2

What are the different componetns of a balanced diet and what do they do- carbohydrates, fats, proteins?

Answer 2

carbohydrates- main source of energy (simple- starch/complex-sugars/bread-indigestible fibre-provides roughagfe)
proteins- essential for growth/repair of tissues
fats- used in cell membrane (phosolipid bilayer)- sepeate cell contents from external envronemt, allow diffusion of substances

Question 3

what are the ourpose of minerals, vitamins, water and fibres

The lack of what mineral can cause anaemia?

Answer 3

minerals- inorganic compounds essential for bodiyl functions
vitamins- used in metabolic processes e.g vitamin C- citrus fruits- help immune sytem fight infections
water- essnetial for bodily functions and to transport substances around body
fibres- essnetial for digestive system to functione.g roughagfe ti seed up passage of food
The mineral iron which means the body is unable to produce sufficent protein

Question 4

what is malnurtition?

Answer 4

cause of an unbalcned diet

• too much food
• too luittle food

Question 5

What is the most common form of malnutrition in the western [developing world]?
health risks i leads to?

Answer 5

obesity
cardiovascualr disease
type 2 diabetes- body becomes insensitive to insulin
gallstones- bile stored in gall bladder
high blood pressure- hypertension in blood

Question 6

What are the causes of obesity?

Answer 6

• lack of exercise
• high consumption of fatty foods/salt
• more energy taken in than expanded by body
• low metabolic rate [genetic]- means slow rate of chemical reactions in body

Question 7

Obesitty can lead to CHD- what decreases the chance of this?

Answer 7

• dietary fibres
• moderate alcohol consumption
• oily fish

Question 8

What increases the risk of CHD and why? [ 2 main thngs]?

Answer 8

1) High salt intake>decreases water potential of cells.more moves in to RBC>increases blood pressure>cause hypertension
[where the blood pressure and diastotle pressure of heart {when its relaxing] is too high>can cause damage to inner lining of artery (atherosclerosis]
2) Both high levels of saturated fats [lipids] and cholesterol would mean more chance of LDL’s meanign more fatty deposits>increased risk of atherosclerosis.

Question 9

For humans plants are?

Answer 9

completely dependant as they are the basis of all food chains>therefore plants are essential as they produce food from photsynthis rather than consumption

Question 10

Selective breeding:

Answer 10

humans breed derirable charactersitics of an organism to make production more efficent

Question 11

In plant you can make production more efficnet by?

Answer 11

• increasign yeidl size
• increasing growth rate
• increasng resitance to pests/disease
• improve plant repsosnes to fertilsiers
• standaring plant rise (make harvestign easier)

Question 12

In animals you can improve?

Answer 12

• rsistance to infection/disease
• increase rate of growth
• increase productivity/yield

Question 13

selective breeding example: tomatoes?

Answer 13

yellow leaf curl virus is devastative to tomatoes
wild tomatoe variet humans found that has evolved a resitance to it
allelue that is resposnible for the resistance
bred into domestic vairety

Question 14

Selective breeding can be used to make domestic variety with?

Answer 14

hgih productivity

Question 15

Selective breeding stages?- Isolation

Answer 15

1) Isolation- orgasnims ar selcted that contain desirbale characterisitics e.g. a cow with high meat prodiction and a huge one [same species]
select the pair that express the strongest genes [1 cow from each isolated pool]
Only these are allowed to breed (1st generatyion)

Question 16

Artifiial selection stage?

Answer 16

2) The offspring produced are sorted carefully and those with the best combinations of the 2 characterisitcs are selected

Question 17

Interbreedign stage?

Answer 17

3) Only hose selected with the best combinaion are allowed to reproduce
Over time, this selective process can result in the characterisitics being exaggerated

Question 18

Modern breeding programmes?

Answer 18

keep detailed records- to prove ancestory of individuals

they apply selection pressure rath than allow natural selection to occur naturally

Question 19

Fertilisers are used to?

Answer 19

-nirtrates/potassium
-minerals that replace inorganic ions in soil which have been removed/absobed by other plant crops
increase growth rate/overall size of plants
Howver, they’re expensive so are onyl used when outweigh cost of buying and applying

Question 20

Pesticides are?

Answer 20

-kill organsim that cause disease
-insecides/fungicides that kill orgaisnms that would reduce yield/impair reprouduction
e.g. fungicides are used to stop fungal growht in leaves
howver, they are expensive but also more resitantt/stronger pathogns may survive blast and devlop a reistant strain that they pass onto osspring.

Question 21

Antibiotics are use?

Answer 21

to kill bacteria without harming the whole organism
- they kill bacteria that wouild reduce growth rate/impari reporduction so they reduce spread of diseases especially amoing intensively farmed animal
Howver, issue of resistance to antibiotics- so discouraged except for a cure fo disease and limtied use encouraged
shouldn’t be used in case if no disease as his could eaisyl rise in a resistant strain

Question 22

what are the 4 main ways bacteria can spoil food?

Answer 22

external digestion- turn it to mush

• visible growht on food
• release toxins
• cause infection

Question 23

Salting/addign sugar?

Answer 23

decreases wat potential in food cells>water moves out of micro-organsim cells though osmosis>dehydrates cells.die

Question 24

Freezing?

Answer 24

slows down enzyem activty- so slower in metabolsim, reproduction and growth

Question 25

Heat Treament/cooking?

Answer 25

hgih heat termeoratuees>distorts 3D tertiary strucutre>denatures enzymes,die

Question 26

Irradiation?

Answer 26

ionisaing radiation to distort 3D tertiary strucure>enzymes denature>die

Question 27

Pickling?

Answer 27

acid/low pH to disrupt binds in tertiary 3D strucure>denature enzymes>cells die

Question 28

adavantages of using mycoprotein?

Answer 28

• no animal welfare issues
  -no animal fats/cholersterol used
  -faster- more efficent
  higher proudciton of protein
  more energy-efficent- more enrgy beign onserved in food chain

Question 29

Disadvantages of using mycoprotein?

Answer 29

• people dislike the idea of eating ‘fungal food’
  -Micro-organism have to be isolated from protein they grow on (huge seperate fermenters- cost?)
• cost of purifying protein
  -risk of infection- ideal conditons for micro-organisms also result in ideal cnditons for pathogens
  Platability- taste/texture isn’t the same

Question 30

BMR?
indiviual is lying down
too many amino acids in diet
holocaust

Answer 30

Basal Metabolic Rate- minimum required enrgy to keep us alive- usually recorded by heat/oxygen lost
studies when a n individual is lying dow, warm after fasting for 12 hours
after holocaust- malnurtitioned prisoners0 showed too rich a protein diet caused harm
too many amino acids>loweed osomotic water potential>(blood full of fats/amino aicds)>water moves out- dehydrates the body

Question 31

what thigns affect BMR?
gender- 
age-
 prenacy-
 BDI-

Answer 31

men have increased
infants have higher
increases with prwegancy
increases with BDI

Question 32

Most people for DRV have?

Answer 32

peak- middle of two extremes of LRNI and RNI

Question 33

Some people have increased DVR's?
pregancy
age
gender
exerecise

Answer 33

atheltes- need more energy- use more up in repsriation
age- need more protein until certain age
gender-men generalyl need mor than women
Pregnancy- 1st 3 months- feottus needs a lot of protein

Question 34

Problems with measuring DVR’s?

obtasianing figures for one age group?

Answer 34

measuring BMR is diffcult
religious ethical differences infleucne diet
grwoth rates/exercise

Question 35

Advantage sof modern farming?

Answer 35

increased yeild (fertilisers)
increased gorwth rate
increased reistiance to pests (insecidices)
selective breeding - GM crops/anuimals e.g. cows with larf=ge size + hgih milk priduction (essential mineral ions)-
meat-essential amino acids
keep up with popualtion growth (globally increasing)
efficent/quick

Question 36

Disadvantages of modern farming?

Answer 36

chemicla fertilsiers to increase yeild- damage ecosystem
soil erosion, salisantion, loss of land, increased diseases
equipment is expensive, hgih fuel (diesal consumoption)
welfare of animals- cows, chickens- minimsie movement to conserve energy