Biology Topic 2 Flashcards
what are lungs
an organ adapted for gas exchange
what is another word for breathing
ventilation
what are alveoli
the site of gas exchange
why do we as humans need lungs
larger and more complex organisms have a smaller surface area to volume ratio and low diffusion distance from skin to organs
how do smaller organisms perform gas exchange if not through lungs
through the skin
why can small organisms afford not to have lungs
they have a large surface area to volume ratio so they can rely on diffusion from the air to perform gas exchange through the skin
what is the movement of the ribcage during inhalation
up and out
what is the movement of the diaphragm during inhalation
contracts and moves down
what is the change in chest volume during inhalation
increase
what is the movement of the ribcage during exhalation
down and in
what is the movement of the diaphragm in exhalation
relaxes and moves up
what is the change in chest volume during exhalation
decreases
what proportion of CO2 is inhales
0.04%
what proportion nitrogen is inhaled
78%
what proportion oxygen is inhaled
21%
what proportion of O2 is exhaled
17%
what proportion Co2 is exhaled
4%
what proportion nitrogen is exhaled
78%
give 4 adaptions of the alveoli to diffusion
well ventilated
lots of them and they are folded
good blood supply
one cell thick cell wall
how does the alveoli being well ventilated help with diffusion
maintains steep concentration gradient
how does having lots of alveoli and them being folded help with diffusion
increases surface area over which diffusion can occur
what does a good blood supply do to help with diffusion in the alveoli
maintains steep concentration gradient
what does a one cell thick cell membrane in the alveoli do to help diffusion
short diffusion pathway enables more diffusion
can you label a diagram of the lungs?
well done!
what type of circulatory system do humans have
double circulatory system
what are the two circuits of the double circulatory system
systemic and pulmonary circuits
what organ does the pulmonary circuit pass through
the lungs
the systemic circuit goes through lungs/body
body
where does the pulmonary artery go
to the lungs
where does the pulmonary vein go
to the heart
where does the vena cava go
to the heart
where does the aorta go
to the body
give the stages of the circulatory system starting with the vena cava
vena cava comes from body to heart
pulmonary artery takes blood to lungs
pulmonary vein carries it back to the heart
aorta carries it to the body
which two blood vessels carry deoxygenated blood
vena cava and pulmonary artery
which two blood vessels carry oxygenated blood
aorta and pulmonary vein
blood is oxygenated where
in the lungs
what is the biggest vein in the body
vena cava
what is the largest artery in the body
aorta
the aorta runs at high or low pressure
high
which side of the heart has deoxygenated blood
the right
which side of the heart has oxygenated blood
the left
the heart is labelled from whose point of view - above or as if you are lying down
as if you are lying down
make sure to swap left and right sides
the heart is a ____
muscle
what type of muscle is the heart made of
cardiac muscle
what keeps oxygenated and deoxygenated blood separate
septum
what is the heartbeat controlled by
cells in the right atrium
where are the pacemaker cells located
right atrium
which of the two (left or right ventricle) has a thicker wall
left ventricle
why is the left ventricle thicker than the right
it needs to increase blood pressure to pump oxygenated blood around the body
can you label a heart?
well done!!
the vena cava feeds into what chamber of the heart
right atrium
the right atrium is linked to what blood vessel
the vena cava
the right ventricle links to what blood vessel
pulmonary artery
the pulmonary artery links to what chamber of the heart
right ventricle
the pulmonary vein links to what chamber of the heart
left atrium
the aorta links to what chamber of the heart
left ventricle
the left atrium links to what blood vessel
pulmonary vein
the left ventricle links to what blood vessel
aorta
how to cells in the right atrium make the heart beat
they trigger electrical impulses
the heart muscle is supplied blood by what ___
coronary arteries
what do coronary arteries supply to the heart
oxygen and glucose
what does CHD stand for
coronary heart disease
what is the issue with CHD
plaque containing cholesterol builds and narrows the lumen of arteries
what is it called when plaque builds up in coronary arteries/more general blood vessel
Atherosclerosis
what is an irregular heart rate (or too fast or too slow) condition known as
arrhythmia
what is arrhythmia treated with
a pacemaker
if heart rate is too fast what happens to blood pressure
too high
give 3 risk factors for CHD
smoking
obesity
high cholesterol
if heart rate is too slow what happens and what condition is this due to
arrhythmia
low blood pressure - insufficient flow of blood and oxygen around the body
what is the issue with a faulty heart valve
chambers don’t shut slo blood can’t be pumped effectively and efficiently
what is heart failure
when damage to the heart causes reduced rate of blood flow
give 3 possible treatments for coronary heart disease
statins
bypass
stent
what are statins
drugs that reduce cholesterol levels in the blood
what is cholesterol
level of fat
give 3 advantages of statins
doesn’t require surgery
easy to take
can be successful
give 2 disadvantage of statins
side effects
expensive for the NHS as its a long term thing
give 3 side effects of statins
headaches
sleeping issues
muscle pain
what is a bypass for treating CHD
adding extra blood vessel capacity (vein usually transplanted from another area of the body)
where do the surgeons get the vein for treating CHD with a coronary bypass
another part of the body
give an advantage of bypass surgery
high success rate
give 2 disadvantages of bypass surgery
may need to be done repeatedly
surgery can cause stroke or heart failure
what is a stent
an inserted small metal mesh tube that widens artery lumen size to restore blood flow to the heart
stents treat early stage/advanced CHD?
advanced
true or false: stents are not used to treat heart attacks
false - they are
give an advantage of a stent
immediately relieves condition
give 2 disadvantages of a stent
can trigger blood clots (and another heart attack therefore)
requires surgery
what is the treatment for arrhythmia
artificial pacemaker to regulate heart rate
give an advantage of artificial pacemaker
low risk procedure
can be successful and massively increase quality of life
give 3 disadvantages of an artificial pacemaker
requires surgery - with risk of infection
battery need replacing
you have to be careful around electromagnetic fields
give 2 possible treatments for leaky valves
mechanical valve replacement
biological valve replacement
give an advantage of mechanical valve replacement
they last a long time
give 3 disadvantages of mechanical valve replacement
can cause blood clots
can damage red blood cells
and so patient has to take blood thinners
what 3 animals can a biological valve replacement come from
pig, cow or human
give 2 disadvantages of biological valve replacement
some patients have religious objections to it
only last 12-15 years
give 2 advantages of biological valve replacement
you don’t have to take blood thinners
(it doesn’t damage red blood cells or lead to clotting)
give 2 possible treatments for heart failure
heart transplant
artificial heart
give a disadvantage of an artificial heart
only a short term fix
give 2 advantages of an artificial heart
won’t be rejected by the body
helps a person that needs a transplant very quickly
give 3 disadvantages of a biological heart transplant
you have to take immunosuppressants for the rest of your life
they are in short supply
there is a risk of rejection
give 2 advantages of a biological heart transplant
doesn’t need to be replaced
allows a person to live after heart failure
what is heart rate measured in
beats per minute
how is cardiac output calculated
stroke volume x heart rate
what is cardiac output measured in
ml/min
what is stroke volume measured in
ml/beat
is blood a cell, tissue or organ
tissue
where is blood made
in the bone marrow
how many components to blood are there
4
what % of blood are red blood cells
45%
what do red blood cells do
deliver oxygen to the body’s cells for respiration
red blood cells don’t have a what
nucleus
why don’t red blood cells have a nucleus
to have more space for oxygen absorption and storage
what shape to red blood cells have
biconcave shape
why do red blood cells have a biconcave shape
to have a large surface area for maximum oxygen absorption
what do red blood cells contain
haemoglobin
what mineral does haemoglobin contain
iron
what makes red blood cells red
haemoglobin
what substance is actually carried in the red blood cell when it picks up oxygen
oxyhemoglobin
what does haemoglobin do in the red blood cell
helps absorb oxygen
what is the function of white blood cells
defends body against infections caused by pathogens
what is the % composition of white blood cells in blood
less than 1%
what % of white blood cells are phagocytes
70%
what does phago mean
eat
what do pathogens contain
enzymes to digest and destroy pathogens
why don’t phagocytes kill pathogens?
they may not be living so they destroy them instead
what is the function of phagocytes
to engulf pathogens by engulfing and digesting them
how do phagocytes destroy pathogens
a pit is formed which the pathogen enters
it is engulfed by the phagocyte as part of phagocytosis
then digested by digestive enzymes
then the remains of the pathogen are absorbed
what is phagocytosis
when the phagocyte engulfs the pathogen
what % of white blood cells are lymphocytes
25%
what is the function of lymphocytes
to create antibodies which cause agglutination and bind to antigens to mark them out for phagocytosis
and release anti toxins to neutralise toxins
what is a third category in white blood cells that is often forgotten
memory cells - ironic
what are memory cells
differentiated white blood cells which respond quickly to pathogens by releasing antibodies
what is the process of making pathogens stick together so its easier for phagocytes to destroy them
agglutination
what are the proteins on pathogens called
antigens
which one attacks/attaches to which: antigens and antibodies
antibodies attacks to antigens - remember that as b comes before g in the alphabet
what is the function of platelets
to clot blood at a wound to prevent loss of blood and stop micro organisms entering the body via the wound
what 2 bad things to platelets prevent
loss of blood
microorganisms entering the body via the wound
what are platelets
small fragments of cells that can clump together and clot due to proteins on their surface
what enables platelets to clot
proteins on their surface
what do platelets not have
a nucleus
give 3 adaptions of the platelets to function
no nucleus
can change shape to form different clots
secrete blood clotting proteins
how does having no nucleus help a platelet to function
makes it smaller
easier to change shape
what is the function of the plasma
liquid part of the blood that suspends cells and platelets
also transports dissolved substances such as antibodies, hormones, CO2, glucose etc
give 3 things the plasma transports
hormones
antibodies
CO2
Oxygen
glucose
what is the % composition in the blood of the plasma
54%
give 2 pros of blood donation
helps those with blood loss/leukaemia
no risk of infection in the UK due to screening procedures
give 2 cons of blood donation
hepatitis C and HIV can be passed on and infect the receiver
procedure can be painful for the donor and lead to weakness or fainting
what 2 conditions can be passed on by blood donation
hepatitis C and HIV
what 2 things can the process of donating your blood lead to
weakness and fainting
what is another word for blood donation
blood transfusion
give 4 features of arteries
smaller lumen diameter
thicker wall of muscular and elastic tissue
thicker connective tissue walls
carries blood at high pressure
why do arteries have smaller lumen diameters
helps maintain high blood pressure
what does the thick wall of muscle and elastic tissue do for arteries
expands and recoils to pulse blood
arteries carry blood at high/low pressure
high
what is the function of arteries
to carry blood away from the heart
arteries carry blood to or from heart
from
give 2 things that maintain high blood pressure in the arteries
thick walls of muscle and elastic tissue and narrow lumen
give 3 features of veins
blood travels at low pressure
larger lumen with irregular shape
thin and weak wall
blood in veins travels at a high/low pressure
low
blood in veins has a smaller/larger lumen with a regular/irregular shape
larger
irregular
describe the walls of veins
thin and weak
what is a venous pump
pressure in veins is too low to flow back to the heart on its own so skeletal muscles contract to move blood by squeezing veins
what parts of the body squeeze veins to move blood around the body
skeletal muscles
veins carry blood to/from the heart
to
how do you remember that arteries carry blood from the heart
arteries = away
give 2 features of capillaries
one cell thick
narrow lumen
what does a one cell thick capillary help capillaries do
have a short diffusion pathway
name 3 things that diffuse through blood capillaries
oxygen, glucose, amino acids, hormones
what size lumen do capillaries have
narrow
a capillary ___runs through organs and muscles
bed
capillary beds have a large _____for efficient diffusion/gas exchange
surface area
what is the function of capillaries
carry blood to and from the body’s muscles and organs
what is the lumen
the tube part of the blood vessel
what do valves do
make sure blood only travels in one direction
where are valves located in blood vessels
in the lumen
give 3 points you could use in a comparative 6 marker about arteries vs veins
wall thickness
lumen size
blood pressure
in a comparative 6 marker what kind of words should you include
comparative words like whereas/however
and more/less/stronger/larger etc
name 4 reagents
Benedict’s SOLUTION
iodine SOLUTION
Biurets SOLUTION
ethanol/sudan III
what word should you include after the name of every reagent
solution
what is the starting colour of beneditcs solution
blue
what is the original colour of iodine
orange
what is the original colour of biurets solution
light blue
what is the original colour of ethanol/sudan III
colourless
what is a strong positive result for Benedict’s solution test
brick red
what is a medium positive result for Benedict’s solution
orange
what is a weak positive result for Benedict’s solution
yellow
what is the negative result for Benedict’s solution test
blue
what extra thing do you need to do to test with Benedict’s solution
heat it in a water Bath
what is the strong positive result for iodine solution
blue/black
what is the negative colour result for iodine
orange
what is the positive result for biurets solution
purple
what is the negative result for biurets
light blue
what is the positive result for ethanol/sudan III
white
what is the negative result for ethanol/sudan III
colourless
what is the only reagent that needs to be heated to work
Benedict’s solution
what is the memory trick for reagents
BP IS BS
Biurets - protein
blue -purple
iodine - starch
BS - Benedict’s - sugar
what does ethanol/sudan III test for
lipids
what does Benedict’s solution test for
sugars
what does iodine solution test for
starch
what does biurets solution test for
protein
what is a control
an additional test to confirm a result is being produced by the independent variable
give a control for a food test experiment
add the reagent to water
Give a method for iodine solution test
- Out food sample in test tube
COVER sample with iodine
Record colour change
Give a method for testing with ethanol
Add fat to test tube
Add ethanol to sample
Put bung in test tube and shake
Observe change from colourless to white
What extra step in testing for lipids do you have to do (working with ethanol)
Shake the mix of lipids and ethanol with a bung on the test tube
Describe a method to test for proteins
Put food sample into test tube
Cover sample with biurets solution
Place bung on test tube and shake
Leave to settle
Check for purple colour if protein present
What extra step in testing for proteins do you take in the method
Shake the mix of protein and biurets solution and leave to settle before recording colour change
Describe a method to test for sugars
Place food into test tube
Set up water bath at 75 degrees
Put drops of Benedict’s into the sample
Place the test tube in the water bath for 5 mins
Check for colour change to brick red or orange
How hot should the water bath in the Benedict’s solution test be
75 degrees
How many minutes should the tube with benedicts and sugars be left in the water bath
5 minutes
How can you increase the accuracy of the food tests experiment
Colour change is produced by a precipitate
So you could weigh the precipitate to find colour change
Colour change is produced by what
A precipitate
What is the digestive system
An organ system which works to digest and absorb food
What is digestion
Breaking down large insoluble food molecules into small, soluble ones
What is absorption
Movement of small soluble molecules form the intestine to blood
What is an enzyme
A biological catalyst - they speed up a reaction but aren’t changed by it
What is bolus
Food after chewing mixed with saliva
What is emulsification
Turning something big into lots of small things
What is egestion
Remaining waste material passed out of the anus as faeces
What is assimilation
Movement of digested food molecules into the cells where they are used
What is optimum for enzymes
The temperature or ph at which enzyme activity is highest
What is the active site
The part of the enzyme where the substrate BINDS
What does denatured mean
When an enzymes active site changes shape
What is a buffered solution
One that is prevented from losing its pH over time
Why do we need to digest food to eat it
Food is large and insoluble so we cannot absorb it until it is digested
What are the two types of digestion
Mechanical and chemical
What is mechanical digestion
Physical breaking down of food by grinding or churning
Give 1 examples of mechanical digestion in the body
Chewing in the mouth
What is the movement of the oesophagus called
Peristalsis
What is chemical digestion
Breakdown of food by enzymes
The enzymes breaks down the -___into the ____
Substrate
Product
Give 4 enzymes
Amylase
Carbohydrase
Protease
Lipase
What substrate does amylase break down
Starch
What does amylase release as a product
Glucose
What does starch get broken down into
Glucose
Where is amylase produced in the body
Salivary glands and pancreas
True or false: the pancreas produces all types of enzymes
True
The salivary glands produce what two enzymes
Amylase and carbohydrase
What does carbohydrase break down
Carbohydrate
What does carbohydrase break carbohydrate down into
Glucose
Give the places that carbohydrase is found in the body
Salivary glands
Small intestine
Pancreas
How many places in the body is carbohydrase produced
3
How many places in the body is amylase produced
2
What does protease break down
Protein
What does protease break protein down into
Amino acids
How many places in the body is protease produced
3
What places is protease produced in
Small intestine
Pancreas
Stomach
The stomach produces what enzyme
Protease
The small intestine doesn’t produce which enzyme
Amylase
what does lipase break down
Lipids
what are lipids broken down into
Glycerol and fatty acids
How many places in the body is lipase produced
2
Two enzymes are only produced in 2 areas of the body: which two?
Lipase and amylase
What is glucose used for in the body
Respiration to release energy
what is excess glucose stored as
Glycogen
What are amino acids used for
Building new proteins
Give an example of a protein
Collagen
What are amino acids useful for
Growth and repair
What are glycerol and fatty acids used for
Energy sources
Hormone production
What type of thing are enzymes
Proteins
What chemical digestion takes place in the mouth
Amylase and carbohydrase
why can bread melt in your mouth
Enzyme digestion of starch and carbohydrates
The ____is squeezed down the oesophagus and rings of ___perform this motion (peristalsis)
Bolus
Muscle
Does the oesophagus do any actual digestion
No
How does the stomach perform mechanical digestion
It contracts to churn the bolus
How does the stomach do chemical digestion
Protease enzyme is released
Does Hydrochloric acid break down food
NO
What is the function of having Hydrochloric acid in the stomach
To create the optimum pH environment for protease to work
Is the stomach acidic, alkaline or neutral
Acidic - very
How can CHD cause a heart attack
If you get injured and an artery gets damaged blood can clot and the added constriction from fatty deposits constrict blood flow
Give 3 symptoms of CHD
Chest pain
Shortness of breath
Faintness
A heart attack
What is a pig valve called
A porcine valve
what is a cow valve called
Bovine valve
What is the function of the liver
Produces bile
What is the function of the gall bladder
Stores bile
Give the 2 ways bile helps to digest fats
Helps lipase to work
Emulsifies fat
How does bile help lipase to work
Creates an alkaline pH environment which is the optimum for lipase to work
As it counteracts stomach acid
Is bile acidic, neutral or alkaline
Alkaline
Why does bile emulsifying fat help to digest lipids
Fats tend to form globules which are hard to digest
Emulsification increases the surface area for lipase to work on
What does fat tend to do
Form globules
Where is bile released into in the body from the gall bladder
Small intestine
Where is bile released from
Liver
What 2 things happen in the small intestine
Digestion and absorption
Give 5 adaptions of the small intestine to absorption
Villi and microvilli
Thin wall one cell thick
Good blood supply
Lots of mitochondria
Lots of digestive enzymes
How do villi and microvilli help the small intestine perform absorption
Increased surface area for diffusion of nutrients
How does a one cell thick wall of the small intestine help the small intestine perform absorption
Short diffusion pathway
What does a good blood supply to the small intestine do to help absorption
Maintains steep concentration gradient
What do lots of mitochondria in the small intestine do to help absorption
Give energy for active transport of glucose at the end of the small intestine
what is taken into blood by active transport at the end of the small intestine
Glucose
How do lots of digestive enzymes help absorption in the small intestine
Food molecules broken down into smaller soluble ones that can be absorbed easily
What is the function of the pancreas
Produces enzymes for chemical digestion
What is the function of the large intestine
Absorbs excess water and mineral ions
What are functions of rectum and anus
Performs egestion
What is waste material passed out of the anus as
Faeces
Faeces are made of what two things
Fibre and bacteria
What are organelles
The parts of a cell
What are cells
The basic building blocks that make up all living organisms
Give 5 examples of specialised cells
Nerve cell
Muscle cell
Red cell
Sperm cell
Egg cell
What is a tissue
Group of cells with similar structures and function
Give 3 examples of tissues
Muscular tissue
Glandular tissue
Epithelial tissue
Nervous
Connective
Phloem /xylem tissue
What are organs
Group of different tissues that work together to perform a specific function
What two tissues make up the stomach
Glandular and epithelial tissue
What does epithelial tissue do
Covers stuff
What is an organ system
A group of organs working together to perform a specific function
Give 3 examples of organ systems
Musculoskeletal system
Nervous system
Circulatory system
Respiratory system
Digestive system
How many organ systems are in the human body
12
What are organisms
Living creatures
Give the 3 stages of an enzyme controlled reaction
Substrate BINDS to the active site
Creates an enzyme substrate complex
The products of the reaction are released
When drawing an enzyme controlled reaction the substrate should fit exactly/shouldnt fit with the substrate shape
Should fit exactly
The active site is ___to the substrate
Complementary
Enzymes can only catalyse a ___type of substrate
Specific
An enzyme denatures in ___conditions
Extreme
Describe lock and key theory - note that this can be an answer for questions that say ‘why can’t ___substrate be broken down by ___enzyme’
The ___enzyme’s active site is the lock
The substrate ___(name it)___is the key
The shape of the active site is specific to the substrate, so no other molecules will fit
Just like one key fits into line lock
Give the 3 sentences for asking a describe question about enzyme activity graphs
Enzyme activity increases from___ to___
It reaches its maximum at __
After this, enzyme activity decreases, reaching 0 at ____
How do you answer explain questions about enzyme activity graphs
Enzyme activity is optimum at___
Above and below this the enzyme begins to denature
Reaching 0 at___
Might need to explain collision theory with rate of reaction as well
Explain how increasing temperature increases rate of enzyme controlled reaction
Enzyme and substrate have more kinetic energy
Frequency of successful collisions between enzyme and substrate increase
Increases rate of reaction up to an optimum
However if temperature is too high or too low the enzyme denatures
Explain why enzymes dont work at non optimum pH s
The active site changes shape as it denatures
Substrate no longer fits
So enzyme cant catalyse the reaction
The __and optimum____of enzymes tell us where it lives in the digestive system
Shape
PH
What is a method for investigating effect of pH on amylase activity
- Put one drop of iodine solution into each depression on the spotting tile
- Add 2cm cubed of the buffered pH solutions into a test tube and label with the pH
- Use pipettes to place 2cm cubed of amylase into the same test tube
- Put 2cm cubed of starch into a new test tube and label it
- Place both solutions into water bath to reach 25 degrees with thermometers
- Remove them once the thermometers in them record 25 degrees
- Add starch to the enzyme and pH test tube and immediately place a drop in the first depression and start the clock
- Mix the solution with a pipette
- Use the pipette to remove 1 drop of the mix every 30 seconds, adding each to a dimple on the spotting tile
- Continue until the mixture remains orange when you do this
- Repeat with other pH solutions
- Plot a graph with pH on the x axis and rate of reaction on the y axis
The dependent variable goes on what axis
The y axis
What equipment do you put drops of iodine in in amylase practical
Spotting tile
What temperature do you use a water bath to heat the solutions to in amylase practical
25 degrees
What is health
State of physical and mental well being
Give 3 reasons for being unhealthy but not diseased
Stress
Poor diet
Difficult life situations
What does stress put as at risk of
Disease
Give 3 ways diet can be poor
Eating wrong types of food
Too much food
Not enough nutrients
Give 3 things that are difficult life experiences that can make you unhealthy but not diseased
Access to free/adequate healthcare
Emotional trauma
Finances
When exam says state one factor that can impact your health dont say what and give 3 possible right answers
Not disease
Diet
Stress
Difficult life situation
What is a disease
A condition in which the normal function of some part of the body is disturbed
What is a communicable disease
A disease caused by pathogens that can be passed from one organism to another
what is the definition of a non-communicable disease
Diseases which aren’t infectious
Cannot be passed from one organism to another
Give 2 examples of non communicable diseases
CHD
Cancer
What is the biggest killer in the developed world
Non communicable disease
Immune reactions caused by a pathogen can trigger things like what
Skin rashes
Asthma
Viruses living in cells can be the trigger for what
What HPV cause for example
Cancers
Cervical cancer
What can physical ill health lead to
Depression or mental ill health
HIV can make you more likely to catch what
TB
A cold can make ___flare up
Asthma
Give 2 non modifiable risk factors for disease
Genetics (ethnicity, gender, family heritage) and age
Give 5 modifiable risk factors for disease
Lifestyle - diet, exercise, smoking
Pollution
Obesity
High blood pressure
High cholesterol
What 3 things can smoking cause
Cancer - especially lung cancer
CHD and other heart diseases
harm to unborn baby development
Give 2 ways unborn baby development can be harmed by smoking
Baby may be excessively small
May be miscarriage
What damage does smoke do in the lungs
It damages the alveoli - presumably clogs them
Chemicals in cigarette smoke increase risk of ________resulting in cancer
Uncontrolled mutations
Give 3 harmful effects of alcohol
Liver damage
Brain function damage
Unborn baby development harmed
Give the general mechanism by which alcohol harms the body
Damages liver cells and neurones by chemicals - and chemicals limit unborn baby development
Give 3 things a bad diet and lack of exercise can cause
Heart disease and CHD
Diabetes
Vitamin deficiencies
How does poor diet and exercise cause CHD/diabetes etc
Increased cholesterol levels and atherosclerosis (fatty deposits creation in arteries)
give 2 carcinogens
smoking and ionising radiation
how does a carcinogen cause cancer
increased risk of mutations leading to uncontrolled cell division
and the development of malignant tumours
what can obesity cause (a disease)
type 2 diabetes
how does obesity lead to type 2 diabetes
increased levels of compounds in the blood that promote insulin resistance
give 4 negative effects on the sufferer of a non communicable disease
no job - causing financial strain
lifestyle change
mental health issues potentially caused neeeding a carer might cause financial strain
give 3 impacts on the family of someone suffering with a non communicable disease
psychological
lifestyle change
financial drain
give 2 impacts on the NHS from non communicable disease
financial costs of treatment
staff/resource shortage
give 3 impacts on the government of non communicable disease
shortage of workers
financial cost of healthcare
reduced taxes = financial cost
what is epidemiology
study of the transmission of disease
what is incidence
number of people diagnosed with a disease in a particular population at a particular time
what is prevalence
the number of people with a particular condition
what is mortality rate
number of deaths per unit of population from a specific disease per year
what causes tumours
uncontrolled growth and division of cells
what are cancerous tumours also known as
malignant tumours
what do malignant tumours do
invade other tissues and spread into the blood and form secondary tumours
what is the name for tumours caused by a malignant tumour
secondary tumours
give 4 features of malignant tumours
made of cancerous cells
form secondary tumours
grow quickly
can invade neighbouring tissue
do malignant tumours grow quickly or slowly
quickly
what kind of cells are malignant tumours made from
cancerous
what are benign tumours made from
abnormal (non cancerous) cells
how quickly to benign tumours grow
slowly
benign tumours tend to be____and in one/many areas
contained
one
give 3 characteristics of benign tumours
made of abnormal cells
grow slowly
contained in one area, usually within a membrane
benign tumours are usually contained within what
a membrane
give 6 risk factors for cancer
smoking
radiation
diet
alcohol
genetics
carcinogens
what type of radiation can lead to cancer
ionising UV radiation
what kind of diet can lead to cancer
high salt, sugar and processed food
what 4 cancers can be influenced by family history of the cancer
breast
skin
prostate
ovarian
asbestos exposure is/is not a carcinogen
is
give 4 examples of pathogens
protist
virus
bacteria
fungus
what is a pathogen
a micro organism that can cause disease
what is the transpiration stream
the movement of water from the roots, to stem and its evaporation out of the leaves through the stomata
what is step 1 in the transpiration stream
water absorbed by root hair cells
give 4 adaptions of the root hair cell
large surface area
lots of mitochondria
thin cell wall
large permanent vacuole
why does the root hair cell need a large surface area
to complete maximum diffusion and osmosis into the cell
why does the root hair cell have lots of mitochondria
active transport of mineral ions
what is the thin cell wall in the root hair cell for
efficient diffusion and osmosis
what is the large permanent vacuole in the root hair cell for
to absorb lots of water
label a root hair cell and draw it
:)
do root hair cells have chloroplasts?
no
what is the protrusion at the end of the root hair cell called
the root hair
name all the structures in a root hair cell
mitochondria
cytoplasm
cell wall
cell membrane
permanent vacuole
ribosome
root hair
nucleus
what is step 2 in the transpiration stream
water is transported up the stem by the xylem
what structure moves water up the stem
the xylem
how do you identify mitochondria
wiggly shape in the middle
how do you identify chloroplasts on a drawing
horizontal lines across it
give 3 adaptions of the xylem
lignin strengthens and thickens walls
no cell walls
hollow cells which are dead
how many directions does water flow in the xylem
one
which direction does water flow in in the xylem
up
xylem transports water from the___to the ____
roots
leaves
does the xylem need energy to transport water up it
no
why doesn’t transpiration need energy
strong cohesion between water molecules due to the hydrogen bonding
what is stage 3 of the transpiration stream
water evaporates out of the leaf via the stomata
the leaf is a plant ____specialised for ___
organ
photosynthesis
____tissues cover a plant
epidermal
stomata are ____in the ___tissue which control gas exchange and _____
pores
lower epidermal
water loss
upper epidermis is ___and ____to allow more light to reach palisade cells
thin
transparent
what is the top layer of the leaf
waxy cuticle
what does the waxy cuticle do
reduces water loss by evaporation
what do the stomata control
gas exchange and water loss
what are two adaptions of the palisade mesophyll layer to their function
lots of chloroplasts to absorb light energy for and perform photosynthesis
on top of the leaf so as to better absorb light
what is the function of the palisade mesophyll layer
to perform lots of photosynthesis
what is the spongy mesophyll for
space for diffusion of gases
the palisade mesophyll layer performs most ___
photosynthesis
what is the function of the phloem
to transport sugars and amino acids up and down the plant
what is the function of the xylem
transportation of water and mineral ions up the plant
where is meristem found in the plant
tips of shoots and roots
meristem can differentiate into ____cell types
many
what layer is below the spongy mesophyll
lower epidermis
what is the singular of stomata
stoma
what control the opening and closing of the stomata
guard cells
when stomata is open water is ___from the leaf
lost
can you label a diagram of a leaf?
:)
what is the second to top layer of a leaf
upper epidermis
what is the third to top layer of the leaf
palisade mesophyll
what is the fourth to top layer of the leaf
spongy meosphyll
what is the fifth to top layer of the leaf
low epidermis layer
what does the lower epidermis layer contain
stomata and guard cells
when the plant has allot of water what happens to the guard cells
water moves into the guard cells by osmosis
this makes them turgid and opens them
so lots of CO2 can enter the leaf for photosynthesis
why do the stomata open when the plant has lots of water
so the plant can do photosynthesis more by letting in more co2 to react with the water
give 4 factors affecting rate of transpiration
wind
temperature
light
humidity
if light intensity is increased what happens to rate of transpiration
increased
as temperature is increased what happens to rate of transpiration
increases
why does rate of transpiration increase with increased light intensity
rate of photosynthesis increases so water is drawn up faster from the stem/the stomata open to let more CO2 in for photosynthesis and some water vapour is let
why does increased temperature increase rate of transpiration
evaporation and diffusion are faster as water particles have more energy
as it gets windier, what happens to rate of transpiration
it increases
why does winder conditions lead to faster rate of transpiration
steeper concentration gradient as water moves off the surface of the leaf more quickly so diffusion is faster
as it gets more humid what happens to transpiration rate
it decreases
why does humidity decrease rate of transpiration
the concentration gradient is smaller so diffusion is slowed
what piece of equipment is used to measure rate of transpiration
potometer
what is measured in the rate of transpiration practical
volume of water absorbed by shoot
why is the volume of water absorbed by shoot measured in the potometer practical
it must be equal to the volume of water lost by transpiration
what can be changed to see the impact of certain variables on the rate of transpiration
environmental conditions
give 3 steps of the photometer practical
leafy shoot is stuck in a test tube with a bung with a hole in it
out in a test tube connected to a reservoir and a capillary tube with a ruler around it and a beaker of water at the end of the capillary tube
and vaseline is applied around the stem to seal it
the ruler is used to measure the distance moved by the air bubble from 0
the reservoir is used to reset the air bubble to 0
always cut the stem of the shoot in the potometer practical in a specific way - describe how
at an angle
why is the shoot cut at an angle in the potometer practical
it reduces the chance of an air bubble getting stuck in the xylem (and the plant dying quickly)
how do you find water volume absorbed in the potometer practical
find the area of the cylinder of water lost by finding radius of cylinder, doing volume of a cylinder with the distance the air bubble moved
what is the function of the phloem
transports dissolved substances from leaves to the rest of the plant for immediate use or storage
what is translocation
the transport of dissolved sugars
translocation is passive true or false
false - it actually requires energy
where are sugars made in the plant
the leaves - photosynthesis
sugars are used for ____throughout the plant
respiration
the phloem is living/dead
living
the___of the phloem extends throughout the whole structure
cytoplasm
give 3 adaptions of the phloem
no nuclei
perforated walls (sieve plate) at one end
companion cells
how does not having a nucleus help the phloem
more space for dissolved sugars
how does the sieve plate help the phloem
allows cell sap to move from one phloem to the nest for effective movement of dissolved sugars
what does the companion cell help the phloem to do
it houses the phloem’s organelles
and provides energy for translocation
draw the xylem and phloem in the roots
the xylem looks like a cross in the roots
and the phloem is the dots in between the cross
draw the xylem and phloem in the stem
ring shape of xylem and phloem with the xylem on the inside and phloem on the outside of the flower shape thing ring of stuff on the edge
why is the xylem like a cross in the root of the plant
allows the root to be strong and push through the soil (xylem is strong due to lignin)
rings of the __show the age of the tree trunk
xylem
the xylem is ___and provides inner/outer support for the stem
strong
inner
what is the word equation for photosynthesis
carbon dioxide + water -light-> oxygen + glucose
give 4 factors affecting rate of photosynthesis
light intensity
CO2 concentration
amount of chlorophyll
temperature
what is the symbol equation for photosynthesis
6CO2 + 6H2O -> C6H12O6 + 6O2
