Organisation Flashcards
how do you prepare a food sample?
- break piece with pestle and mortar
- transfer to beaker, add distilled water
- stir with glas rod to dissolve some food
- filter solution using funnel lined with filter paper to get rid of solid bits
how do you use the Benedict’s Test to test for sugars?
- prep food sample, transfer 5cm3 to test tube
- prep waterbath at 75ºC
- add about 10 drops Benedict’s solution using pipette
- place test tube in water bath using test tube holder, leave for 5 mins
- tube pointing away from you
- reducing sugar: blue to green/yellow/brick-red
how do you use Iodine solution to test for starch?
- prep food sample, transfer 5cm3 to test tube
- add few drops and gently shake to mix contents
- starch: browny-orange to black/blue-black
how do you use the Biuret Test to test for proteins?
- prep food sample, transfer 2cm3 to test tube
- add 2cm3 biuret solution and gently shake to mix contents
- protein: blue to pink/purple
how do you use the Sudan III Test to test for lipids?
- prep food sample no filter and trasfer 5cm3 into test tube
- add 3 drops Sudan III stain solution using pipette and gently shake to mix contents
- solution stains lipids
- lipids: seperate two layers, top bright red
what is the thorax?
- top part of body
- seperated by diaphragm
- lungs
what are the lungs?
- big pink sponges
- protected by ribcage
- surrounded by pleural membranes
the air we breath in…
-goes down the trachea
the trachea is split…
- into two tubes
- bronchi (bronchus)
- goes to each lung
the bronchi is split…
- smaller tubes
- bronchiole
what are alveoli?
- small bags at end of bronchiole
- surrounded by network of blood capillaries
- gas exchange takes place
how does gas exchange occur of blood returning to lungs from rest of the body?
- blood passes next to alveoli
- oxygen diffuses out of the alveolus (high conc.) into blood (low conc.)
- carbon dioxide diffuses out of blood (high conc.) into the alveolus (low conc.) to be breathed out
- blood reaches body cells, oxygen is released from red blood cells
how does gas exchange occur of blood reaching body cells?
- oxygen released from red blood cells (high conc.) diffuses into body cells (low conc.)
- carbon dioxide diffuses out of body cells (high conc.) into blood (low conc.)
- carried back to the lungs
how can you calculate the breathing rate in breaths per minute?
breaths per minute = number of breaths/ number of mins
the first one in the circulatory system
- right ventricle pumps deoxygenated blood to lungs to take in oxygen
- blood returns to heart
the second one in the circulatory system
- left ventricle pumps oxygenated blood around organs
- blood gives up oxyegn at body cells
- deoxygenated blood returns to heart to be pumped out to lungs again
what is the heart?
- pumping organ
- keeps blood flowing around body
what are the walls of the heart made of?
-muscle tissue
why does the heart have valves?
- blood flows right direction
- prevents backwards
how does the heart pump blood around the body?
- LEFT:pulmonary vein, left atrium, left ventricle, aorta
- RIGHT: vena cava, right atrium, right ventricle, pulmonary artery
how does the heart get its own supply of oxygenated blood?
- coronary arteries branch off aorta
- surrounds heart
what are the different types of blood vessels?
- arteries - carry blood away from heart
- capillaries - involved in exchange of materials at tissues
- veins - carry blood to heart
how does the arteries carry blood under pressure?
- heart pumps blood out at high pressure, artery walls are strong and elastic
- thick walls
- contains thick layers of muscle to make them strong and elastic fibres to allow them stretch and spring back
describe the capillaries
- really tiny
- carry blood really close to every body cell to exchange substances to maintain concentration gradient
- permeable walls so substances can diffuse in and out
- supply food and oxygen, takes away waste like CO2
- wall one cell thick for short diffusion distance
- large surface area maximise exchange
how are the walls of capillaries adapted?
- one cell thick
- increases rate of diffusion
- decrease distance
how does veins take blood back to the heart?
- capillaries join up to form veins
- blood low pressure in veins wall dont need to be as thick
- bigger lumen than arteries
- valves
why does veins have a bigger lumen than arteries?
-helps blood flow despite low pressure
how can you calculate the rate of blood flow?
rate of blood flow = volume of blood/number of mins
what is coronary heart disease?
- coronary arteries supply blood to heart muscle
- blocked by layers of fatty material building up
- causes lack of oxygen to heart muscle
- heart attack
how do we use stents to keep a person’s heart beating?
- tubes inserted inside arteries
- keep open so blood can pass through to heart muscles
how do stents lower risk of heart attacks in people with CHD? (ADVANTAGES)
- effective for long time
- recovery time for surgery is quick
what are the risks of stents?
- complications during operation
- infection from surgery
- thrombosis: patients develop blood clot near stent
what is cholesterol?
-essential lipid for bodily function
what happens if you have too much cholesterol in the bloodstream?
- fatty deposits forms inside arteries
- leads to CHD
what are statins?
- drugs reduce amount of ‘bad’ cholesterol present in bloodstream
- slows down rate of fatty deposits forming
what are the advantages of statins?
- reduce bad cholesterol reduces risk of stroke, CHD and heart attacks
- increase amount of beneficial cholesterol in bloodstream, remove bad cholesterol from blood
- may prevent other diseases
what are the disadvantages of statins?
- long-term drug taken regularly, could forget
- negative side effects: headaches, kidney failure
- time for affect to kick in
what are artificial hearts?
- mechanical device pumps blood
- temporary fix: alive until donor heart available
- help recovery, allows heart to rest and heal
- permanent fix: reduces need for donor heart
what is the main advantage of an artificial heart?
- less likley rejected by body immune’s system than donor heart
- made from metals and plastic, not living tissue
- body doesn’t recognise as foreign and attack
what are the disadvantages to an arficial heart?
- surgery: bleeding and infection
- doesn’t work as well as healthy natural: electrical motor can fail
- blood flow not as smooth: blod clots lead to strokes
- prevent:drugs to thin blood
- problems with bleeding if injured
how can heart valves become damaged?
- heart attacks
- infection
- old age
what is the effect of damaged heart valves?
- valvue tissue stiffens, won’t open properly
- leaky: blood flows both directions
- blood doesn’t circulate as effectively
how can you treat severely damaged heart valves?
- replace with biological valves
- mechanical valves
what is the advantage to valve replacement?
- much less drastic procedure
- than whole heart transplant
what is the disadvantage to valve replacement?
- major surgery
- lead to problems with blood clots
what does the heart do when someone loses alot of blood?
- pumps remianing red blood cells around body
- get oxygen from body
- aslong volume of blood topped up
how is artificial blood e.g saline used?
- replace lost volume of blood
- safe if no airbubbles get in blood
- keeps ppl alive if 2/3 rbc lost
- gives pateint time to produce new rbc
what happens if a patient can’t produce more red blood cells?
-blood transfusion
what is the definition of health?
-state of physical and mental wellbeing
what are communicable diseases?
- spread person to person
- between animal and people
what is communicable diseases caused by?
- bacteria
- viruses
- parasites
- fungi
what is an example of communciable diseases?
- measles
- malaria
what are non-communicable diseases?
- can’t spread
- lasts long time
- gets worse slowly
what is an example of non-communicable diseases?
- asthma
- cancer
- coronary heart disease
what increases your chance of suffering a communicable disease such as influenza?
- weak immune system
- body less likely able to defend itself against pathogen
how are allergic reations triggered?
- immune system reactions
- caused by infection
- by pathogen
what can sometimes trigger mental health issues?
- suffer severe physical health problems
- impact everyday activities
- life expectancy
what are some factors that can affect your health?
- poor diet
- stress
- life situation: access to meds, healthy food, condoms
what are risk factors?
-things linked to increase in likelihood of developing disease
what are the risk factors in a person’s life?
- lifestyle: excercise
- environment: air pollution
- substances in body: abestos
give an example of how lifestyle factors impact nationally?
- ppl from deprived areas
- more likley smoke, poor diet, don’t excercise
- higher incidences of cardiovascular disease, obesity, Type 2 diabetes
how do risk factors link to non-communicable disease?
-several interacting with eachother
give an example of how lifestyle factors impact gloablly?
- non-communicable disease more common in developed countries
- higher income
- buy high-fat food
give an example of how lifestyle factors impact locally?
- individual choices
- affects local incidence of disease
what are risk factors that can directly cause disease?
- smoking
- smoking when pregnant
- obesity
- alcohol
- cancer
what is the human cost of non-communicable diseases?
- tens of millions deaths per year
- lower quality life
- shorter lifespan
- affects loved ones
what are the organs of a plant?
- stems
- roots
- leaves
list the plant tissues
- epidermal tissue - covers whole plant
- palisade mesophyll tissue - photosynthesis
- spongy mesophyll tissue - contains big air spaces to allow gases to diffuse in and out
- xylem and phloem - transports substances
- meristem tissue - found at growing tips of shoots/ roots, differentiate into different types of plant cells for growth
what tissues do leaves contain?
- epidermal
- mesophyll
- xylem
- phloem
what is the function of the epidermal tissue?
- covered with waxy cuticle
- reduces water loss by evaporation
what is the function of the upper epidermis tissue?
- transparent
- light pass thru to palisade layer
what is the function of the palisade layer?
- lots of chloroplasts
- near top of leaf
- absorb most sun
what is the function of the xylem and phloem?
- forms network of vascular bundles
- transports water and nutrients to entire leaf
- takes glucose away produced by photosynthesis
- supports structure
what is the function of the lower epidermis?
- gas exchange
- little holes called stomata
-lets CO2 directly into leaf
what is the function of the guard cells?
-controls opening and closing of stomata in response to environmental conditions
what is the function of the spongy mesophyll tissues?
- contains air spaces
- increases rate of diffusion of gases
what are phloem tubes?
- columns of elongated living cells
- small pores in the end walls
- allows cell sap to flow through
what does phloem tubes transport?
- food substances (dissolved sugars)
- transport both ways
- translocation
what are xylem tubes?
- dead cells joined ned to end
- no end walls between them
- hole down middle
- strengthened with lignen
what does xylem tubes carry?
-water and mineral ions
transpiration stream: movement of water from roots, thru xylem, out of leaves
how does transpiration cause the loss of water in plants?
- evaporation and diffusion
- evaporation slight shortage of water in leaf, more water drawn up from rest of plant thru xylem vessels to replace
- constant transpiration stream of water thru plant
- diffusion: more water inside than outside, escapes thru stomata
what affects the transpiration rate?
- light intensity
- temperature
- air flow
- humidity
how does light intensity affect the transpiration rate?
- brighter the light = greater transpiration rate
- stomata closes when dark = no photosynthesis
- can’t open to let CO2 in
- very little water can escape
how does temperature affect the transpiration rate?
- higher temp = faster transpiration rate
- water particles more energy
- to evaporate and diffuse out of stomata
how does air flow affect the transpiration rate?
- better airflow (stronger wind) = greater transpiration rate
- water vapour swept away
- maintaining low concentration of water in the air outside the leaf
- fast diffusions from area of high conc to low conc
how does humidity affect the transpiration rate?
- drier the air around leaf = faster transpiration rate
- humid air = less difference between
how can you estimate the rate of transpiration?
- measure uptake of water by a plant
- record starting position of water bubble
- record distance moved per hour
- keep conditions constant e.g temperature and air humidity
what shape are guard cells?
- kidney shape
- opens and closes stomata
what happens to the guard cell when the plant has a lot of water?
- fills, goes plump and turgid
- stomata opens so gases can be exchanged for photosynthesis
what happens to the guard cell when the plant has a short amount of water?
- loses water becomes flaccid
- stomata closes
- stops too much water vapour escaping
describe the inner and outer walls of the guard cells?
- thin outer walls
- thickened inner walls
- make opening and closing work
how does the guard cells save water?
- sensitive to light
- close at night
where is the stomata situated on the leaf?
- underside
- lower surface is shaded and cooler
- less water lost thru stomata
how does movement of potassium cause guard cells to open?
- increases concentration inside guard cells
- water moves into cell through osmosis
- cell swells unevenly so stomata opens
- thick part of wall is less flexible than thin part of wall
