organisation Flashcards
what is coronary heart disease:
-what can happen as a result
-when coronary arteries get blocked by fatty material build up,
-blood flow restricted as lumen gets smaller
-less oxygen reaches the heart muscle
-can cause a heart attack
what is a stent:
tube placed in an artery to expand it out
benefits of stents
-disadvantage
-quick surgery
-lasts a long time
-surgery always has risks (ie. infection, heart attack)
-possibility of developing a blood clot near stent (thrombosis)
what is a statin?
-what can it treat
-medication that alters the balance of cholesterol
-can treat cor hear dis, heart attacks, strokes by reducing amount of LDL in blood and increases good HDL
what is cholesterol?
-effects of LDL
-an essential lipid that body produces and needs to have in order to function properly
-too much of the bad (LDL) can cause fatty deposit build up in arteries and cause coronary heart disease
disadvantages of statins:
-usage
-side effects
-time
-long term usage (possible to forget)
-can have serious side effects (ie. kidney failure, memory loss)
-takes time to be effective
features of stomach:
-enzymes, prod?
-contracts muscular walls to push around and mix food
-prod. pepsin, a protease enzyme, breaks down proteins into amino acids
-prod HCl, kills bacteria, provides right environment for pepsin to work
role of small intestine:
-where digested food is absorbed into the blood
role of pancreas in digestion:
-prod most of the digestive enzymes
which r then released into the small intestine in the form of pancreatic juices
role of gallbladder:
-2 main functions
-where is it made (the substance in gallbladder)
secretes bile into small intestines
-bile: neutralizes stomach pH so that conditions are ideal for dig. enz. to function (bile is alkaline)
-emulsifies fat (lipids) (breaks it down to tiny droplets) , big surface area for dig. enz. to work on
-bile made in liver, stored in gbladd.
adaptations of sm. int.
-v, blood
-many villi, large SA, absorb. of food quicker
-villi, only 1 layer of surface cells, short diffusion pathway for nutrients
-very good blood supply, maintains conc. gradient
what happens in large intestine:
leftover material from s. int. pushed into it, excess h2o absorb.
-left with faeces, stored in rectum till removed
order of food journey in digestion
-mouth
-oesophagus (gullet)
-stomach
-small intestine (+pancreatic juices + bile)
-large intestine
-rectum
two main roles of digestion
-break down large food molecules into smaller molecules
-absorb these food molecules into body
what does amylase break down?
starch to maltose
which enzymes does the pancreas prod?
amylase, protease, lipase
levels of organisation: small to big
-organelles (eg. nucleus, mitochondria)
-cells
-tissues
-organs
-organ systems
-organisms
the definition of an organ
-group of different tissues
-working together to perform a common function
why incr. in temp is not good way to incr. react. rates
-requires lot of energy
-can increase non-useful reactions
-can damage cells
what is a catalyst
substance that speeds reaction, w/o being changed or used up
-enzyme: type of cat. (biological cat.)
factors effecting enzyme action
-pH
-temperature
in both cases, if two high or low, bonds holding the enzyme together will start to break apart,
changes active site shape
substrate no fit
said to be denatured
what does optimum temp mean
temp that gives the highest enzyme activity
importance of iron in diet
-important component in hemoglobin
-if not enough, could develop anemia, where not enough oxygen is able to get to tissues
importance of calcium
-needed for healthy teeth and bones
-else could develop rickets
need for fibre
helps food move through intestines properly
-stops diarrhea/ constipation
monomer for
-carbohydrates
-proteins
-lipids
-simple sugars (glucose, fructose)
-amino acids
what atoms are carbs, proteins, mainly
-C,H,O
-C,N,H,O
how do you start a food test
crush up the sample using mortar and pestle
-put crush in a beaker w/ distilled water & stir with glass rod till some dissolves
-filter out any solids with filter funnel paper
what is the test for sugars
-benedicts test
-only tests for reducing sugars
-put 5cm3 of food solution in test tube, put that in water bath heated to 75 C for 5 mins.
-if sugars present solution will turn green, yellow or brick red depending on conc.
what colour is benedicts solution
blue
test for starch
iodine test
-5cm3 of food solution, put few drops of iodine in, it is now brown colour
-shake, if starch present, solution = blue black
positive colour change for iodine test
blue black
positive colour change for benedicts test
green, yellow or brick red
test for proteins
-biuret test
-2cm3 of food solution, +2cm3 of biuret solution, turning it blue
-shake,
-if proteins present, will change to pink/ purple
positive colour change for biuret test
pink/purple
test for lipids
-sudan III
-5cm3 food solution (not filtered)
-add 3 drops of sudan sol.
-if lipids present, should get stained,
-as lipids separate from water, bright red layer at the top forms
our body uses carbohydrates as the main ….. source
energy
starch is broken down by …… into smaller …… called …….
-amylase
-sugars
-maltose
3 places where amylase made:
-salivary glands
-pancreas
-small intestine
3 places where proteins broken down
-stomach (where its called pepsin)
-pancreas
-small intestine
proteins are broken down by …… into …..
protease
amino acids
fats (lipids) are broken down by …. . these prod …. and ….. . ….. is prod in the …. …… and ……
-lipase
-glycerol & fatty acids
-pancreas & small intestine
…… is a ….. of glucose produced by plants
-starch
-polymer
maltose molecules are broken down further by …… into glucose
-maltase
How does bile help with the digestion of lipids?
It emulsifies the lipids…
…which increases the surface area for lipase enzymes to break them down
when we breathe in air it goes down the …… then stems out to …… then down ……. then to ……
-trachea
-bronchi
-bronchioles
-alveoli
alveoli is the site of … ……..
gas exchange
features of alveoli:
-1 cell thick
short diffusion pathway, inc. rate of CO2 & O2 can diffuse across
-very large surface area
-alveoli walls r moist
allows gasses to dissolve increasing rate of diffusion
-positive concentration gradient betw the high oxygen in alveoli and deoxygenated haemoglobin
and high con. of co2 in blood and low in alveoli, then when in alveoli can be breathed out
how is co2 transported around the body
it is dissolved in the blood plasma, (carried around by blood plasma)
the circulatory system : transports
oxygen and nutrients across body
deoxygenated blood goes from the heart to the lungs….
where it gains oxygen and flows back to the heart
the top chambers are called …… the bottom chambers are called ……
- atriums
- ventricles
role of the valves in the heart
to prevent blood flowing in the wrong direction
blood flows in through the …… into the……. and through the …… into the ……
-vena cava & right atrium
-pulmonary vein & left atrium
blood coming into the pulmonary vein is coming from the lungs so is ……. and blood from the right atrium is coming from the loop around the body so is …….
- oxygenated
- deoxygenated
what happens if the pacemaker and the right atrium does not work properly
it is replaced by an artificial pacemaker,
small device that is placed below the skin above the heart
that has a wire that can carry and elec current to heart
telling it to contract regularly
an ……. is any vessel that carries blood away from the heart and a ….. is any vessel that carries blood to the heart
artery
vein
where does the heart get its oxygen and nutrients from
the coronary arteries
The _______ ventricle has thicker walls because it has to pump blood all the way around the body.
left
the …… ventricle pumps deoxygenated blood to the lungs to take in oxygen
right
The journey of blood around the body
body tissues ➔ vena cava ➔ right atrium ➔ right ventricle ➔ pulmonary artery ➔ lungs ➔ pulmonary vein ➔ left atrium ➔ left ventricle➔ aorta ➔ body tissues
the capillaries exchange
nutrients and oxygen with tissues
why is diffusion across capillaries easy
because the walls are permeable
features of capillaries
really small (lumen tiny)
exchange substances with cells (nutrients + oxygen)
takes away a waste products (CO2)
Which of the following substances are exchanged between the blood in the capillaries, and the body tissues?
waste:
Carbon dioxide
Urea
nutrients:
Oxygen
Glucose
If you consider all the blood vessels inside of a human body, which type of blood vessel accounts for the majority of the cross-sectional area?
Capillaries
In which order does blood flow through the three types of blood vessels?
heart ➔ artery ➔ capillaries ➔ veins ➔ heart
four main things that blood consists of
red blood cells
white blood cells
platelets
plasma
what is the role of red blood cells
to carry oxygen from the lungs to our bodies tissues
adaptations of an RBC
-biconcave - large SA for absorbing oxygen
-no nucleus - more space for hemoglobin and oxygen
what do white blood cells do
(wbc’s have a nucleus)
- phagocytosis, engulf pathogens
- antibodies, binds onto pathogens, helps destroy them
- antitoxins, neutralise any toxins
what are platelets
-small fragments of cells, don’t have a nucleus
-float in our blood, find wounds and help blood clot
-so blood will stop and microorgs cant get in
what is plasma and what does it carry
The nutrients: glucose, amino acids, fatty acids, and glycerol
The waste products: carbon dioxide and urea
Other bits: hormones, antibodies
what is artificial blood?
-salt water (saline)
-adds volume to blood
-doesn’t have any rbc, so no o2 transport
-can only replace 1/3 of our blood
what is a tumor
when an abnormal mass of cells goes through uncontrolled growth and division
differences between malignant and benign tumors
malignant:
can you spread to other parts of the body and create secondary tumors, causes a lot of damage and can be fatal
benign:
stays in one place, usually in membrane, not cancer
adaptations of upper epidermis cells
almost transparent so sunlight can pass through them to get to chloroplasts in palisade
adaptations palisade mesophyll cells
lots of chloroplasts so lots of photosynthesis
what is the waxy cuticle
a thin layer of lipids on top of leaf to stop water loss
when air flow is high outside leaf…
the water vapour outside will be blown away, inc gradient betw inside & outside leaf, so rate of transpiration will be higher and more water will diffuse out
when humidity is high outside leaf…
-con gradient decr.
-more water vapour out than in
-less transpiration
what is the xylem and what does it do
-Made up of dead cells joined together, creating a continuous tube.
-Strengthened with a substance called lignin
-Allows the movement of water and mineral ions from the roots to the stem and leaves, where it evaporates and leaves the plant.
This is called the transpiration stream.
what is the function of lingin in xylem
Lignin makes it strong and waterproof, so water will not leave except at bordered pits, allowing minerals to go to specific places in the plant.
what is phloem
Elongated cells with pores in the cell ends
-Food substances can be moved in both directions, from the leaves where they are made for use, or from storage (underground) to parts of the plant that need it.
-This process is called translocation.
what is transpiration
-the loss of water vapour from the leaves and stems of the plant
-it is a consequence of gaseous exchange, as the stomata are open so that this can occur
what is translocation
the movement of food substances made in the leaves up or down the phloem, for use immediately or storage
how does good blood supply incr. efficiency of absorption in small intestine
maintains concentration gradient
Describe how the small intestine is adapted for efficient absorption.
-villi provide a large surface area
-walls of villi one cell thick for shorter diffusion distance
-(small intestine is) very long, increasing time (for absorption)
-good / efficient blood supply to maintain concentration gradient
-cells have many mitochondria for (aerobic) respiration for active transport
Name two other organs in the digestive system that produce carbohydrase.
-pancreas
-small intestine
-salivary glands
pacemakers spread small. …..
electrical impulses to heart muscle causing contraction
three parts of the circulatory system:
blood, blood vessels and heart
