October exams part 1 Flashcards
Respiration
Respiration is the process of transferring energy from glucose, which happens constantly in every living cell
What are the two types of Respiration?
Anaerobic and Aerobic Respiration
How does Respiration release energy?
In the Form of ATP
What happens when a cell needs energy?
ATP molecules are broken down and energy is released
What is more efficent Aerobic Respiration or anaerobic Respiration?
Aerobic Respiration
What is the Chemical and Word Equation for aerobic Respiration?
Glucose + Oxygen –> Carbon Dioxide + Water
C6H12O6 + 6O2 –> 6CO2 + 6H2O
How many ATP molecules are produced per molecule of glucose?
32 Molecules
How many ATP molecules does anaerobic respiration produce per molecule of glucose?
2 molecules
What is the difference between Anerobic Respiration and Aerobic Respiration?
Glucose is only Partially Broken down in Anaerobic
Anaerobic doesn’t use O2 at all
Aerobic Respiration uses plenty of O2
Word equation fro anaerobic respiration?
Glucose –> Lactic Acid (+Energy)
Word equation Anaerobic Respiration in plants?
Glucose –> Ethanol + Carbon Dioxide
Practical to detect CO2 Production using an Indicator?
Use Hydrogen-Carbonate Indicator
Orange –> Yellow if present
What other forms of Energy does Aerobic Respiration transfer to?
Heat energy
How do Plants exchange Gases?
Diffusion
Where are waste Products expelled in Plants?
Through little holes in the undersides of leaves called Stomata
Explain the Gas exchange of a Plant during Photosynthesis?
When a Plant is photosynthesising it uses up a lot of CO2, so there’s hardly any inside the leaf. Luckily this makes more CO2 move into the leaf by diffusion (from an area of high conc. to low conc.)
At the same time lots of O2 is being made as a waste Product of Photosynthesis. Some is used in respiration, and the rest diffuses out through the stomata (moving from an area of higher concentration to a lower concentration)
What effects the Net Exchange of Gases in Plants?
Light Intensity
Explain the Net exchange of Gases during the day?
During the Day plants make more oxygen by photosynthesis than they use in respiration. So in daylight, they release Oxygen. They also use up more Carbon Dioxide than they produce, so they take in Carbon Dioxide.
Explain the Net Exchange of Gases during the night?
At night though plants only respire- there’s not enough light for photosynthesis. This means they take in Oxygen and release Carbon Dioxide - Just like us.
Explain how leaves are Adapted for Efficient Gas Exchange?
(leaf has) large surface area;
2. thin + short diffusion distance;
3. stomata + allows gases in/out / diffusion;
4. spongy mesophyll + increase surface area / gas diffusion /
gas movement / air movement;
5. moist + allows gases to dissolve;
What happens to the Stomata in the dark?
It begins to close. Photosynthesis can’t happen in the dark, so they don’t need to be open to let CO2 in. When the stomata are closed, water can’t escape. this stops the plants drying out.
What happens to the plant when the supplies of water from roots start to dry up?
This stops the plant from photosynthesising (BAD), but if they didn’t close they may dry out and die
If the CO2 CONC. Decreases what colour will the hyrdogencarbonate indicator become?
Orange –> Purple
I the CO2 CONC. stays the same what colour will the hydrogencarbonate indicator become?
Stays Orange
If the CO2 CONC. increases what colour will the hydrogencarbonate indicator become?
Orange –> Yellow
What is the Thorax?
The upper part of your body?
Explain where the air breathed in Goes?
The air that you breathe in goes down the trachea and to the Bronchi (Bronchi are just two Bronchus’)(Either Bronchus). it then moves through smaller tubes called the Bronchioles and at the end of the Bronchioles there are small bags of Alveoli. this is where Gas Exchange will take place.
Breathing?
The process that moves air in and out of the lungs. Also known as ventilation
Gas Exchange
The exchange of oxygen and carbon dioxide at the lung surface via diffusion
What flaws are there with the Bell jar model?
Glass is different matieral to our ribs
Glass have a different stimulus and movement
Not to scale
No ribs, intercostal muscles and movement of the chest
Describe the process of Inhalation?
Diaphragm contracts and flattens in shape. The external intercostal muscles contract –> Ribs move upwards and outwards. The Volume of the thorax increases causing the air pressure inside the thorax to decrease causing the air to enter the lungs
Describe the process of Exhalation
The diaphragm relaxes and returns to domed shape. The internal intercostal muscles relax allowing the ribs to drop back down. If breathing hard the external intercostal muscles contract helping the ribs to move down. The Volume of the thorax decreases. Causing the air pressure to increase inside the thorax. Causing Air to leave the lungs
What are the Adaptations of the Alveoli?
Large SA--> This means there are more alevoli giving a greater change for gas exchange and diffusion to occur Very Thin (One cell thick) --> This provides a short diffusion pathway Moist Lining --> Allows gases to dissolve and then diffuse across the lining Good Supply of Blood --> As there is a 360 degree capillery network that maintains Concentration Gradient
What is the Purpose of the Alveoli?
Site of Exchange
What effect does Carbon Monoxide had on the Body?
Combines with haemoglobin in the red blood cells instead of Oxygen to reduce the abillity to carry Oxygen –> Reduce oxygen (Possible Death)
What effect does Nicotine have on the Body?
Highly Addictive drug which increases heart rate
What effect does Tar have on the Body?
Contains carcinogens (cancer causing chemicals)
What do Tobacco contain?
Carbon Monoxide
Nicotine
Tar
What consequence does smoking have on the lungs?
EMPHYSEMA
BRONCHITIS
LUNG CANCER
Explain Emphysema?
Alevoli Burst
Decrease gas exchange due to reduced surface area
.thickening of alveoli wall for diffusion
gaseous exchange slowed down
Explain Bronchitis?
Inflamation of Bronchi and Bronchles
More Mucus Produced
Airways Become Damaged
What Effect might Smoking have on the Heart?
High blood Pressure-Arteries narrow, less blood able to travel through blood vessel at any one time, thus increasing Blood Pressure
CHD- Damages the lining of arteries, build of fatty matieral, narrows the lining
Cardiac Arrest- Narrowing of Blood Vessels to the Point where no blood is able to pass through. Starvation of O2 to organs
Why does Excercise increase the Breathing Rate?
This is because your muscles respire more during excercise. They need to be supplied with more O2 and have more CO2 removed, so your breathing rate increases.
What are the four Main components of Blood?
Plasma
Platelets
Red Blood Cells
White Blood Cells
What is Plasma and what is it’s use?
Plasma is a pale yellow liquid which carries just about everything in your body.
Red and White Blood Cellls and Platelets
Digested Food Products from the gut to all body cells
Carbon Dioxide
Urea
Hormones
Heat Energy
What are Platelets?
Small fragments that help Blood to Clot?
Why are BLOOD CLOTS USEFUL?
Blood clots stop you losing blood and prvent microorganisms from entering the wound
What are the purpose of Red Blood Cells
Carries Oxygen
Contain haemoglobin (which is what gives blood it’s colour)
OXYGEN + Haemoglobin –> OxyHaemoglobin
Don’t have a nucleus –> frees up space for more haemoglobin, to carry more oxygen
What are Pathogens?
Are Microoorganisms that cause disease
How do Phagocytes destroy pathogens?
Phagocytes move towards the pathogen, binds to it, pushes a sleeve of cytoplasm to surround it. It then engulfs it inside the vacuole and digestive enzymes are released to break pathogen down.
How do Lymphocytes destroy antigens?
Neutralise pathogens as they act as antitoxins
Marks pathogens for phagocytes
Lumps pathogens together for mass destruction
State three ways in which you can become immune to a disease
Specific shape for antibodies
Natural genes
Antibodies transfer –> immunification
How do Vaccinations work?
Vaccinations usually involves injecting dead or inactive pathogens into the Body. These carry antigens, so even though they’re harmless they still trigger an immune response-your lymphocytes produce antibodies to attack them.
This means that memory Cells will also be produced and will remain in the blood, so if live pathogens of the same type ever appear, the antibodies to kill them will be produced much faster and in greater in numbers.
Where are the Lungs Located?
Behind the rib cage in the thorax
What is the Purpose of the Ribcage?
To protect the Lungs
What is the Function of Cartilage (Trachea)?
Keep Trachea Open
C shaped because when the Osephagus is used it allows the food to move down
What are the three different types of blod vessels?
Arteries
Capillaries
Veins
Where does the blood flow of arteries go to?
These carry the blood away from the heart
What is the function of Capillaries?
These are involved in the exchange of materials at the tissues
What is the function of Veins?
These Carry blood to the heart
What is the largest artery in the body?
Aorta
What are the function of Goblin Cells?
To prevent dirst and foreign substances from being contracted as they are stuck to it.
Makes Mucus as well
Function of Cillia?
Tiny hairs that move the mucus up the throat to the pharynx
Mucus sticks to dirt
Example of Vein?
Vena Cava
What is the Blood pressure like in
Arteries
Veins
Capillaries
Arteries- High to give blood quicker
Veins- Low
Capillaries- Low
What are the wall structures like in
Arteries
Capillaries
Veins
Artery- Thick Muscle with elastic fibres which allow arteries to expand. It has smooth muscle
Veins- Skeletal Muscle
Capillaries- One Cell thick
Internal Diameter (Lumen)? For all three Blood Vessel
Artery- Very small
Veins- Very Wide
Capillaries - Very narrow
Which of the Blood Vessels has a valve? and why?
Veins–> To help keep blood flowing in the right direction
What is the largest Blood Vessel?
Artery
Pulmonary
Hepatic
Renal
Pulmonary –> To do with Lungs
Hepatic –> To do with the liver
Renal –> To do with the Kidneys
Why do we need Blood Vessels?
We need Blood Vessels to carry oxygenated blood around the Body
Why Capillaries are good for diffusion?
Walls are only one cell thick. This increases the rate of diffusion by decreasing the distance over which it happens
What is the purpose of the heart?
To supply and pump oxygenated blood around the body
Explain how veins are adapted to carry blood around the heart?
Bigger Lumen than arteries to help blood flow despite lower pressure
Valves to keep blood in the right direction
Explain how arteries are adapted to carry blood around the heart?
The elastic fibres allow arteries to expand
The heart pumps the blood out at high pressure so the artery walls are strong and elastic
How does Blood flow through the heart?
.The right atrium of the heart recieves deoxygenated blood from the body (through the vena cava)
. The deoxygenated blood moves through to the right ventricle, which pumps it to the lungs (via pulmonary artery)
. The left atrium recieves oxygenated blood from the lungs (through the pulmonary vein)
. The oxygenated Blood then moves through to the left ventricle, which pumps it out round the whole body (via aorta)
.
What are the use of Valves in the Heart?
To prevent the Backflow of the Blood
Why does the left ventricle have a much thicker wall than the right ventricle?
This is because it needs more muscle because it has to pump blood around the whole body, whereas the right ventricle only has to pump it to the lungs.
Which part of the Blood has higher blood pressure?
The left side because it needs to pump the blood around the whole body.
Why does EXCERCISE increase heart rate?
When you excercise, your muscles need more energy, so you respire more.
OR
You need to get more O2 into the cells and remove more CO2.
For this to happen the blood has to flow faster, so your heart rate increases.
This is because Excercise increases the amount of CO2 in the Blood
High levels of Blood CO2 are detected by receptors in the aorta and carotid artery (artery in the neck).
These Receptors send signals to the Brain
The Brain sends signals to the heart, causing it to contact more frequently and with more force
How does adrenaline help control the Heart Rate?
When an organsim is threatened or in a dangerous situation
Adrenal Glands releases adrenaline
Adrenaline binds to specific receptors in the heart. This causes the cardiac muscle to contract more frequently and with more force, so heart rate increases and the heart pups more blood
This incrases Oxygen supply to the tissues, getting the body ready for ….
When does CHD occur?
When the coronary arteries that supply the blood to the muscle of the heart get blocked by layers of fatty matieral building up.
What can CHD lead to?
The narrowing of arteries –> Blood flow Restricted –> Lack of O2 to the heart muscle - possible heart attack
What can lead to CHD?
A Diet high in saturated fat –> Fatty deposits forming inside arteries , which can lead to CHD
What 4 Things could cause CHD?
A Diet high in saturated fat
Smoking
Lack of excercise
Stress
What can cause CHD?
A Diet high in saturated fat
Smoking
Lack of excercise
Stress
Explain how smoking can cause CHD?
Somking increase blood pressure, which can cause damage to the inside of the coronary arteries. Chemicals in cigarettes can also cause damage. This damage makes it more likely that fatty deposits will form, narrowing the coronary arteries.
Explain how being inactive can cause CHD?
It can lead to High Blood Pressure, which can damage the lining of the arteries. This damage makes it more likely that fatty deposits will form
What can CHD lead to?
Angina, Heart Attack, Stroke.
What is Angina?
When the Coronary Arteries contract
. less blood is supplied to the muscle cells of the heart
. less O2 is supplied
. less respiration can happen
. Heart cells may respire anaerobically –> Chemical change
. Triggers pain called angina
What is Myocardial Infarction?
If atheroma within endothelium of a coronary artery ruptures
. the damaged endothelium and exposed collagen will result in the clotting cascade and clot formation inside the artery
. Reduces or stops blood flow to heart muscles reducing or stopping supply of O2, Reducing or Stopping aerobic respiration which reduces energy available
. Starved heart cells are said to be ischaemic
. The longer they starve the morge damaged they get
. The greater the area of heart muscle starved, the more serious the consequences will be
. I.E. Heart attack
What are the features of the red blood cell?
Bioncave disc for large SA:V
No Nucleus so they cannot split
Purpose of White Blood cells?
Fighting Pathogens
How do animals increase their chance of survival?
By responding to changes in their external environment
What is a stimulus?
A change in the internal or external environment
What are Receptor cells, what are their purposes and where are they found?
Receptor cells are in the sense organs (Eyes, Ears, Nose, Tongue and Skin)
Groups of cells that deteckt external stimuli
What are Effector Cells?
Effector Cells are cells that bring about a response to stimuli
How do Receptors and Effectors communicate?
Nervous System and Hormonal System
What three nerurons make up the nervous system?
Relay Neurone, Motor Neurone and Sensory Neurone
What does the CNS consist of
brain and spinal cord only
How quick are nervous system responses?
Very Rapid responses because neurones transmit information using a high speed electrical impulse
What are Reflexes?
Automatic Responses to certain stimuli
What are they uses of Reflexes?
They reduce the chances of being injured
What is a reflex arc?
The route taken by the information in a reflex
What happens when your hand touches a hot object?
This is detected by receptor cell, an electrical impulse is sent along a sensory neurone
This electrical impulse goes to the CNS
In the CNS the sensory neurone passes on the message to the relay neurone
Relay Neurones relay the electrical impulse to a motor neurone
The Impulse then travels along the motor neurone to the effector
The Muscle contracts and moves your hand away from the candle
What is the function of the Conjunctiva?
The Conjunctiva lubricates and protects the surface of the eye
What is the function of the Sclera?
The tough outer layer that protects the eye
What is the function of the Cornea?
The cornea refracts light into the eye. The cornea is transparent and has no blood vessels to supply it with Oxygen so Oxygen diffuses in from the outer surface
What is the function of the Iris?
Controls the diameter of the Pupil and therefore how much light enters the eye
What is the function of the Lens?
The Lens focuses the light onto the Retina
What is the Lens covered in?
It’s covered in light receptors called rods and cones.
Rods are more sensitive in dim light but can’t sense colour. Cones are sensitive to colours but aren’t so good in dim light.
Where are cones found?
Cones are found in the Retina and the Fovea
What is the function of the Optic Nerve?
Carries electrical impulses from the receptors to the Brain
What is the purpose of the pupil reflex?
Controls the size of the Pupil
Describe what happens to the pupils in light?
Circular Muscles contract, Radial Muscles relax therefore Iris Constricts. More Light enters the eye
Describe what happens to the pupils in the dark?
Circular Muscles relax, Radial Muscles contract therefore the Iris dialates resulting in more light entering the eye
What is the purpose to the action in light?
To reduce the amount of light that enters the pupil which can cause damage to your retina
What is the purpose to the action in the dark?
To allow the amount of light to enter the pupil so that we can see better in the dark
What is Accomodation?
Allowing more or less refraction by contracting the lens
What happens to your eye when Focusing on a near object?
.Light Rays entering the eye are divergent . Cornea bends the light . the lens become fatter . Suspensory ligaments slack . Ciliary Muscles contract . Lens bend the light a lot
What happens to the eye when focusing on a distant object?
Light rays entering the eye are nearly parallel . Cornea does not bend the light . Lens become thinner . Suspensory Ligaments become taut . Ciliary Muscles relax. . Lens bend the light a little
When can short sightedness be caused
When the eyeball is too long meaning that the light is focused at a point in front of the Retina
Also when the lens is too thick meaning that the light is focuses at the point in front of the Retina
How can short sightedness be treated?
Concave Lenses to partially unfocus the light before it enters the eye
Soft or Hard Contact Lenses and refract the light
Laser Surgery can be used to bend the shape of the cornea so it refracts the light to a greater or lesser extent
What is Mitosis?
Mitosis is when a cell reproduces itself by splitting to form two cells with identical sets of chromosmes
Is a Daughter cell a diploid or haploid?
Diploid
WHat does Mitosis Form?
Two genetically identical daughter cells
How many Chromosomes do Sperm Cells and Oecytes have?
23 each
Differences between Mitosis and Meiosis?
Mitosis 1 cell division/ Meiosis 2 cell division
Mitosis produces Diploid cells/Meiosis produces Haploid cells
In Mitosis Daughter cells are genetically identical to the parent cell/ In Meiosis Daughter Cells are not genetically identical to parent cell
What are the phases of Mitosis
Prophase –>
.DNA condeses to form X shaped chromosme
. Nucleus membrane deterorates
. Chromosome floats into cytoplasm
Metaphase –>
. Chromosomes line up at the equator of the cell
. Spindle fibres attach to the centramid
Anaphase –>
. Spindle Fibres contract pulling Chromatids to either poles of the cell
Telephase –>
.Chromatids react with the Pole of the Cell
. 46 chromosomes are found on either side
.Nuclear Membrane forms around each group of genetic material
Cytokinesis –>
. Cytoplasm divides forming a burrow therefore forming two new burrow cells
What are Sperm Cells/ Oecytes also known as?
Gamete or Germ Cells
Why is Mitosis necessary?
To make new cells for growth and repair
What are the differences between Sexual and Asexual Reproduction?
Asexual Reproduction involves only one parent
The offspring will have been genetically identicaly to the parent –> No variation in the genetic makeup between the offspring and the parent
. Usually Mitosis
Sexual Reproduction:
Involves the fusion of a male gamete and a female gamete
2 parents –> Offspring contains a mixture of the parents genes –> The offspring is not genetically identical to either point
What is the Point of the Male Reproductive System?
To Produce Sperm
What is the purpose of the Urethra?
Carries urine/ejacualte semen during urination/ejacualtion
Explain, with reference to features shown in the diagram, how lung tissue enables
efficient gas exchange.
- alveoli + increase surface area;
- (alveoli) thin / one cell thick + short diffusion distance;
- capillary (wall) is thin / one cell thick + short diffusion distance;
- capillary / blood + maintains concentration gradient /
diffusion gradient; - moist + allows gases to dissolve;
Explain the effect on enzymes when there is a decrease in temperature
- less (kinetic) energy at low temperatures;
- fewer collisions / less movement at low temperatures / eq;
- enzyme denatures;
- changes active site / eq;
- substrate can no longer bind / eq;
What are the role of enzymes?
. catalyse / speed up / increase rate / lower activation energy / eq;
2. (chemical) reactions / (metabolic) reactions;
Advantages of Deforestation?
Advantages:
- employment / jobs / income / eq;
- (wood) for building / furniture / paper / eq;
- fuel;
- land / space for farming / land / space for building homes;
- access by roads;
EXPLAIN 3 WAYS FARMERS COULD INCREASE PRODUCTION ON A FISH FARM?
keep adults from young / keep sizes apart / eq;
E control intraspecific competition / large fish eat small fish /
prevent young being eaten / eq;
OR
2. M keep different species apart / use nets / use cages / eq;
E prevent fish being eaten / control predation /
control interspecific competition / eq;
OR
3. M antibiotics / vaccination / prevent overcrowding;
E control disease / infection;
OR
4. M selective breeding / use growth hormones / use GM fish;
E for named desired quality such as mass / yield;
OR
5. M use wrasse / insecticide / pesticide / biological control / eq;
E to prevent / remove / kill parasites;
Maintaining WATER Quality and Food Quality
Purpose of the urethra
Carries urine/ ejaculate semen dueing urination or ejaculation
Purpose of Prostate Gland
Seminal Vesicle and prostate gland produces liquid that is added to sperm to produce semen
How does the penis become erect?
Penis has erect tisdue which when filled with blood makes the penis erect
Purpose of scrotum sack
Hangs behind penis and holds testicles
Purpode of Sperm Duct
Where sperm travels through
Female reproductive system
Role to make ova
To provide the right environment for the growth and development of the fertillised egg
Process of Fertillisation
Sperm ejaculated into vagina cervic and into the fallopian
Meets fallopian into fallopian tube and fertilised with it to form a zygote
Zygote goes through a number of cell divisions and goes back into the uterus whereny it implants onto the endometrium lining of the uterus. Implantation results in the formation of HCG which stopd the shredding od endometrium poving which can be picked by pregnancy tests
What do Hormones do in terms of Human Reproduction
They can involve in promoting sexual characteristics during puberty
What happens during puberty
The body releases sex hormones which triggers the formation of secondary characteristics
Primary sexual characteristics
What you are born with
Secondary sexual characteristics
Characteristics that develop during puberty
What can oestrogen cause
Extra hair in the underarms
And the pubic region
It causes womans hips to widen helping having a baby
Development of breats
Causes the release of ovum from the ovary and therefore the start of periods
What does Testosterone cause
Extra hairbin armpits and pubic region
Muscles to develop
Shoulders to become broader
Penis and testicales to enlargen
Produces more sperm in testes
Deepening of the voice
What 4 stages are in the menstrual cycle
Stage 1
Day 1 when menustration starts this is where the iterus lining breaks down
Stage 2
The uterus lining starts to build up again
Happens between day 4-14
Stage 3
Egg develops and is released from ovary and travels through the fallopian tube
Stage 4
Endometrium wall is maintained day 14-28. If by day 38 there has been no implantation of the fertillised egg then the endometrium wall starts to shed again
What 4 hromones control the menstrual cycle
FSH
Oestrogen
LH
Progestorone
Explain the role of Hormones in the menstrual cycle?
Pituitary Gland signals ovaries to produce a cerain molecule/ hormone
FSH results into the stimulation of Oestrogen
Egg cells start to produce Oestrogen
Once Oestrogen produced by follicle Oestrogen is released by the blood stream and to the pituitary gland in order to inhibit the further production of FSH
Oestrogen causes the lining of the uterus to grow
Pituitary Gland produces LH and peaks at day 14
LH is responsible for release of egg (ovulation)
Progestorone maintains lining in the uterus
Remnants need to survive inside the ovary
If implantation doesnt take place HCG wont be released
If it isnt released corpus luteum doesnt survive
Progesterone will continuously be produced and the lining will be maintaindd
Male reproductive part of flowes?
Anther and Filament
Purpose of Anther?
Contains the pollen grains which produces the male gamtetes
Purpose of Filament?
Supports the anther
What is the female reproductive part?
Carpel
What are the female reproductive parts?
Stigma, style and Ovary
What is Pollination?
Transfer of pollen from an anther to the stigma so that the male gamete can fertillise the female gamete in sexual reproduction
What is Cross Pollination?
Type of sexyal Reproduction where pollen from the Anther of one plant is transferred to the stigma of another plant
Features of Cross Pollinated Plants?
Brightly coloured to attract insects
Scented Flowers and nectaries
(glands that secrete nectar) to attract insects
Make big stivky pollen grains so it is easier to transfer to each plant
Stigma of plants are sticky as they go from plant to plant
Features of Wind Pollinated Plants?
Small Dull Petals
No nectaries or strong scent
Produces a lot of small light pollen grains that can be carried by the wind
Long filaments that hang anther outside the flower, so that a lot of pollen gets blown away the wind
Large feathered stigma to catch pollen
Fertillisation in the plant?
Nucleus of the male gamete passes from pollen and in to the ovule via the ovary. At the ovule, the nucleus of the male gamete fertillises with the nucleus of the female gamete
Germination?
When seeds start to grow
What are the conditions needed for Germination to occur?
Water- Needed to activate enzymes that break down the food reserves in the seed
Oxygen-
Respiration
Suitable Temp-
So Enzymes do not denature
What are the Purpose of Nitrate Ions
Contain Nitrogen for making amino acids which then create proteins for Growth
What happens when there is a lack of Nitrate?
Causes Growth to be stunted
Leaves to turn Yellow
What are the Purpose of Phosphate Ions?
Contain Phosphorus which are needed to make DNA and Cell Membrane
Also Needed in Respiration
What happens when there is a lack of Phosphate Ions?
Causes poor root Growth
All leaves to turn purple
What are Potassium Ions used for?
Helps Enzymes for respiration and Photosynthesis
What happens when there is a lack of Potassium Ions?
Poor flower and root Growth
What are Magnesium Ions needed for?
Needed to Make Clorophyll for Photosynthesis
What happens when there is a lack of Magnesium Ions?
Lack of Chlorophyll
Yellow Chlorophyll
Why can Unicellular Organisms solely rely on diffusion to meet its energy demand?
Steep Concentration Gradient
Diffusion Pathway is Shorter
SA:V is higher
This increases the rate of Diffusion
Why can Multicellular Organisms not solely rely on Diffusion?
Low SA:V
Diffusion pathway is higher
Metabolic Demands of Multicellular organisms are much higher than Unicellular Organism
What are the two transport systems?
Xylem and Phloem
What does the Xylem do?
Carries water minerals from roots to shoots
Undirectional
What does the Phloem do?
Transports sugars such as sucrose and amino acids from where they are made in the leaves to the other parts of the plant
hence Bidirectional
(Uses Translication)
What is Translication?
The Movement of food substances around the plant
What is Transpiration?
Loss of water from a Plant
Where does Transpiration usually take place?
Mainly at the surface of the leaf
What effects the rate of Transpiration?
Light Intensity
Temperature
Windspeed
Humidity
What are Carbohydrates made up of?
C, H2 AND O
What makes up a monosaccharide?
Multiple Monomers (Glucose)
What makes up a Disaccharide?
2 or more Monosacharrides
What is Protein made up of?
C, H, O AND N
What is the Monomer for Proteins?
Amino Acids
What is the Polymers for Proteins?
Polypeptide Chains
What are Lipids made up of?
C, H AND O
What are the monomers of Lipids?
Glycerol and Three Fatty Acids
What are the Polymers of Lipids?
Triglycerole
What are the bonds between the fatty acids and Glycerol made up of?
Esters
What food can test for?
Glucose
Starch
Iodine
Protein
What is the Test for Glucose?
Benedicts Test
5CM3 of food into test tube
Place Test tube in Water Bath
Add Benedicts Solution
If there is a Low Conc. of Glucose (Blue –> Green/Yellow)
If there is a High Conc. of Glucose (Blue -> Black/Red)
What is the test for Starch?
Iodine Test
5scm3 of food sample into test tube
Add a few drops of iodine solution
Browney Orange –> Blue/Black
What are the tests for Proteins?
2CM3 of food sample in a test tube
Add 2cm3 of biuret Solution
Gently Shake
Blue –> Pink
What are the Tests for Fats and Oils?
Food Substance in test tube (2CM3)
Add 2cm3 of Ethanol
Equal Amount of distilled water (2cm3)
If lipids are present –> Milky White Emulsion forms
Colourless –> Milky White
How to Find out Energy from food?
Use foods that burn easily (Pasta)
Weigh a smaller amount of food and skewer it onto a mounted needle
Add a set Volume of Water to a boiling tube
Measure temperature of water –> Initial Temp
Set fire to piece of food using bunsen burner
Hold the ignited food substance underneath the boiling tube containing water
Measure Temp (c’) Again –> Final temp
Energy in Food = Q X C X Delta T
Energy in Joules = Energy in Food (in J)/ Mass of food (in g)
What breaks down Starch into Maltose?
Where is it found?
Amylase
Mouth and Stomach
What breaks down Maltose into Glucose?
Maltase
Stomach
What breaks down Proteins into Amino Acids?
Proteases
In Stomach
What breaks down Lipids into Glycerol and Three Fatty Acids?
Lipases
Explain the process of Digestion?
Mechanical Digestion (Via Teeth) Amylase Present breaks down starch enzymes
Food moves down the Oesophagus via Peristalsis
The Food then enters the Stomach
(-Stomach pummels food with the muscular walls
-Produces the protease enzyme called pepsin which digests proteins into amino acids.
–> Stomach contains HCl to kill Bacteria and to provide optimum temp and pH for Pepsin)
Small Intestine Produces Proteases, amylase and lipase enzymes to completed digestion
This is where nutrients are absorbed out of Alimentary Canal into body.
The Large Intestine absorbs excess water in ileum from faecial matter
The Rectum is where the last part of the faeces is stored and when it is full it is released through the anus
What are three parts of the Small Intestine?
Duodenum
Jejunum
Ileum
How does the Duodenum Assist Digestion?
Where Majority of Digestion Takes Place
(Pancreatic Juice and Bile enters the duodenum via the Ampulla of Vater to assist and to enable absorption of molecules to occur)
Where is Bile Produced? and where is it stored?
Made in the liver
Stored in the Gall Bladder
What does the Pancreas do?
Produces enzymes such as lipase, amylase, protease which is released into the intestines (Also produces insulin)
What does Bile do?
Neutralises acidic contents of the stomach
Emulsifies Fat into tiny droplets
(Increases the surface area for which the lipase enzyme can work on)
How is the Intestine adapted for its role in absorption?
Very long (More time to get absorbed)
Contains villi whch has Microvilli
(High SA:V)
Very Good Blood Supply –> Maintaining Concentration gradient that ensures rapid absorption of food particles
How Does Peristalsis work?
Muscular Contraction, which is circular, along the length of the alimentary tract to promote the passage of food substance towards the anus
Eplain the process of making a fruit from two plants?
Pollen grain lands on stigma of the flower
Pollen Tube forms out of the pollen grain through, stigma, style, ovary and to the ovule where it meets female gamete
Fertilisation
Zygote divides via Mitosis
Ovary of flower forms fruit
What happens when seeds take in Water?
Start to grow using store of energy
First root grows downwards and shoots grows up
Finally extra roots grow and first green leaves appear
Where do Germinating seeds get their energy from?
Food Stores
What dos a developed seed contain?
Embryo and Food Store
What happens when a seed starts to germinate?
Glucose from food store produces energy for growth via respiration
What happens one the plant has grown enough to produce green leaves?
Photosynthesis
Factors that aren’t affected by variation/Environment?
- Eye Colour
- Natural Hair Colour
- Blood Types
Factors that are affected by both Genes and Environment?
- Height
- Weight
- Skin Tone
- Sporting Ability
- Intelligence
Theory of Evolution?
Life began as a simple Orgnaism from which more complex organisms developed
Natural Selection?
Survival of the Fittest
Process by which Evolution took place
Organisms that contained more advantageous traits evolved and succeeded in passing their genes to their offspring
Why can’t variation caused in the environment (such as losing a finger) cannot be passed down to offspring?
It’s only genetic variation
Mutation?
A change in Genetic Code (Random)
Why do Majority of Mutations have no effect on the body?
This is due to the degnerate nature of the genetic code
Many groups of bases code for the same amino acid
What External Factors could make it more likely that there are mutations?
Ionising Radiation
Mutagens
How can Mutagens cause Mutations?
Chemicals in tobacco causes the DNA to change meaning that they are much more likely to become cancerous
Mutagens cause faulty proteins –> Regulatory Proteins don’t do their job on contrlling rate of cell cycle –> Rapid growth of cells –> Too many abnormal + normal cells –> Cells die –> Cancer
What is a Genotype?
All the genes that are present in your body
What is a Phenotype?
All the Characteristics that you express
How to make Yoghurt from Bacteria?
All equipment is sterilised to kill bacteria and prevent chemical contamination
Milk is pasteurised at 85 – 95°C to kill bacteria
contamination with other
bacteria could slow the production of the yoghurt by competing with the Lactobacillus for the lactose in the milk
It could also spoil the taste of the yoghurt
Milk is cooled to 40 – 45°C and Lactobacillus bacteria is added
The mixture is incubated at this temperature for several hours, while the Lactobacillus bacteria digest milk proteins and ferment (digest) the sugars in the milk (lactose)
The Lactobacillus bacteria convert the lactose into lactic acid and this increased acidity sours and thickens the milk to form yoghurt
It is then stirred and cooled to 5°C to halt the action of the bacteria
Flavourings, colourants and fruit may be added before packaging
Fermentation?
Microorganisms break-down sugars anaerobically
Selective breeding?
Organisms are selectively bred to develop the best features for offspring
Process of Selective Breeding?
From Current Stock, make sure you select organisms with the desired characteristics
Breed these two together
Select the best of the offspring
Breed the best of the offspring together
Continue this process over generations, the desirable trait gets stronger and stronger
Genetic Modification?
Enzymes can be used to cut up DNA and can be used to join DNA together
Explain the process of Genetic Modification?
Identify the Gene of Interest
Use restriciton enzymes to cut out the gene of interest
Use the same restriction to cut the vector DNA
Insert the gene of interest into the vector
Use Ligase enzymes to join the different pieces of DNA together to produce recombinant DNA
Introduce the modified plasmid into a bacteria cell
Provide the right culture conditions to allow bacterial growth to take place within fermenter
Bacteria will express human insulin protein that can be purified and used to treat diabetes
What are the different types of Stem cells?
Embryonic Stem Cells
Adult Stem Cells
Are stem cells differenitated or undifferentiated?
undifferentiated
How can stem cells become differentiated?
Via differentiation
Where are Adult Stem Cells found?
Bone Marrow
What type of cells can Adult Stem Cells be converted into?
What type of cells can Embryonic Stem Cells be converted into?
Adult Stem Cells –>
Specific types of blood cells
Embryonic Stem Cells –>
Any type of cell
Pros for Stem Cell research?
Helps cure diseases to replace faulty cells
Negatives of Stem Cell Research?
They can become contaminated in labs and contaminated with a virus
Each one is a potential life
Plants?
,Multicellular
.Photosynthesise
.Cell walls made of cellulose
.Plants store carbs as starch or sucrose
Animals?
.Multicellular .No photosynthesis .No Cell walls .Has Nervous System .Can move around .Store Carbs as glycogen
Fungi?
.Some are single celled
.Others have a body called a mycelium, which is made up of hyphae, which is a thread like structure and contains a lot of nucleus
.No Photosynthesis
.Cell walls made of chitin
.Saphotrophic Nutrition
.Store Carbs as glycogen
Saprotrophic Nutrition?
1 (feed on) dead / rotting / decomposing / eq;
2 enzyme(s);
3 extracellular / outside / external / eq;
4 digests / digestion / digestive;
5 absorption / eq;
Protoctists?
.Single Celled and Microscopic
.Some have chloroplasts and are similar to plant cells
.Others are more like animal cells
Bacteria?
.Single Celled and Microscopic .No Nucleus .Contain a circular Chromosome of DNA .Some can Photosynthesise .Most bacteria feed off each other organisms
Viruses?
.Particles and are smaller than Bacteria
.Reproduce only inside living cells. (Parasite)
.They infect all types of living organisms
.Loads in different Shapes and Sizes
.No cellular Structure
.Have a Protein Coat around some Genetic matieral DNA or RNA
Examples of Fungi?
Yeast
Mucor
Examples of Protoctists?
Chlorella (Plant-cell like)
Amoeba (Animal-cell like) - lives in Pond water
Plasmodium (Causes Malaria)
Examples of Bacteria?
Lactobacillus
Pneumococcuss (causes pneumonia)
Examples of Viruses?
Influenza Virus (flu)
Tobacco Mosaic Virus
HIV (causes Aids)
Osmosis?
The Movement of Water Particles from an area of high water potential to an area of low water potential through a partially permeable membrane until a dynamic equilibrium is reached
Factors that affect Enzyme activity?
Temp c’
pH
What are the differences between egestion and exrection?
- Egestion is the act of removing toxic metabolic waste whereas Excretion is the Removal of Waste Products
- Excretion (Made in cells), Egestion (Not made in Cells)
- Egestion (Faeces), Excretion (Urine)
Three examples of excretion in the body?
- Urination. Sweating and Breathing
What does Urea contain?
Nitrogen
Explain the cycle of Urea?
- The body cannot store amino acids.
- Excess amino acids are carried to the liver in the blood stream.
- In the liver the amino acids are broken down into a carbohydrate (which is converted to glycogen to be stored) and urea.
- The urea is released from the liver back into the blood stream.
- Blood is filtered by the kidneys and the urea is removed.
What are the functions of the Sphincter Muscle in the Urinary System?
Controls when urine is released from the bladder into the urethra
What is the Urethra?
A tube which carries urine from the bladder to outside the body
Function of the Bladder?
Urine is stored here. It has stretchy walls so it can store large quantities
Function of Ureter?
Carries urine to the bladder
What is the function of the Liver in the Urinary System?
Urea is produced here
Describe the Process of Ultrafiltration?
Blood from the renal artery flows through the glymerolus at high pressure
The high pressure causes water, ions; glucose, urea to filter out of the glymerolus and enter the Bowman’s capsule
The membranes between the blood vessels in the glymerolus and the Bowman’s capsule act like filter, so big molecules like proteins and blood cells are not able to be squeezed out.
They stay in the blood. The filtered liquid in the Bowman’s capsule is known as the glymeroles filtrate.
Describe the process of Selective Reabsorption?
As the filtrate flows through the nephron, useful substances are selectively reabsorbed into the blood
All the glucose becomes reabsorbed at the proximal convuluted tube
The reabsorption of glucose requires active transport
Sufficient Ions are reabsorbed, not excess ions
Sufficient amount of water is reabsorbed from the collecting duct into the blood by Osmosis. Remaining water is excreted as urine
The remaining substances form urine.
This continues out of the nephron through the ureter and down bladder where its stored before being released by the urethra
Osmoregulation?
When the body has to continously balance the amount of water coming in against the amount of water going out
What happens if there is a low water level in the blood?
Pituitary releases ADH
ADH increases permeability of distal tubule and collecting duct and water is reabsorbed into blood vessels
Small volume of hypertonic urine
Normal of potential blood
Importance of Upper Epidermis?
Transparent to allow lught to pass through to palisade mesophyll
Importance of Lower Epidermis
Lower Surface Area of leads with gaps called stomata
Importance of Palisade Mesophyll?
Full of chloroplasts to maximise absorption of sunlight for Photosynthesis.
Regularly shaped so can be tightly packed together
Importance of Waxy Cuticle
Water Proof Layer to help reduce water loss
Importance of Spongy Mesophyll?
Air spaces between cells to allow movement of gases directly to cells increases SA:V
Features of Xylem Cells?
- Hollow tubes made of dead cells, as the cells die the cell walls between each other disappear to leave a single continuous tube.
- Water and dissolved mineral ions are transported upwards (from roots to leaves)
- Has rings of lignin surrounding the vessel – lignin is waterproof and very strong to stop the xylem vessels collapsing.
Features of Phloem Cells?
Transports sugar e.g. sucrose and other food molecules e.g. amino acids around plant
- Movement of these molecules is called translocation
- Can move either up or down
- Made of living cells
- Companion cells provide the ATP for the phloem sieve tube cells (no nucleus).
- The end walls of the tube cells have pores through which food is transported from cell to cell- this is called the sieve plate
Where are the Xylem and Phloem found?
Vascular Bundle
How does the movement of Water occur in the Xylem Stream?
Water evaporates from leaf via transpiration
. Water moves out of xylem into mesophyll layer by Osmosis
. This creates a water potential gradient in the leaf and water is drawn out of the xylem
. As the water molecules form hydrogen bonds between one another this creates tension
.Water forms a continuous, unbroken column from mesophyll down to xylem and root due to the cohesion between water molecules
. Doesn’t break due to adhesion of water with xylem walls
Factors affecting the rate of transpiration?
temperature, wind speed, light intensity and humidity
How does Wind speed affect the rate of Transpiration?
Water vapour is removed quickly from outside the leaf by air movement.
This increases the water potential gradient between the most air in the air spaces and outside the lead. This increases the rate of diffusion of water out of the leaf.
How does light intensity affect the rate of transpiration?
More stomata open to allow CO2 to diffuse the leaf for Photosynthesis
This means more water is able to diffuse out of the leaf as there is an increased surface areas for diffusion
How does Humidity affect the rate of transpiration?
Diffusion of water vapour out of the leaf slows down as the leaf is already surrounded by moist air.
This is because the water potential gradient has been reduced (or removed). This decreases the rate of diffusion of water out of the leaf
How does Temperature affect the rate of transpiration?
The higher the temperature the greater the rate of transpiration
The greater the temperature, the greater the kinetic energy of the water particles moving via the transpiration stream
And therefore the greater the rate of of which water particle exit the leaf via diffusion
What is a Hormone?
A chemical that travels vias the bloodstream to a distant site and acts upon a target receptor to induce a specific biological response
Differences between Exocrine and Endocrine Glands?
Exocrine Glands secrete into the external environment
Exocrine Glands Have ducts
Endocrine Glands secrete hormones
The target of Gland is v close in an Exocrine Gland
Where is insulin produced?
Pancreas
What is the role of Insulin?
Converts glucose into glycogen for storage in the liver and muscles
Movement?
an action by an organism or part of an organism causing a change of position or place.
Sensitivity?
the ability to detect or sense changes (stimuli) in their surroundings and to make appropriate responses.
Micropropogation?
Cells are scraped from the parent plant (these cells are known as explants)
The cells are transferred to a sterile petri dish containing nutrient agar
Hormones are added to encourage plants to grow into small masses of tissue (callus tissue)
Tissue continues to grow and forms plantlets that can be transferred to individual potting trays and develop into plants
Why are cloning plants helpful for commerical purposes?
It allows a variety of a plant with desirable characteristics to be produced:
cheaply
with a greater yield (a large number of plants can be produced)
quickly
at any time of the year
It can also ensure diseases prevalent in other areas of the world are not imported and spread by ensuring native varieties of plants are produced in large enough quantities to supply demand in one country without importing plants from abroad
Animal Cloning?
the diploid nucleus from a body cell (specifically from the udder) of an adult sheep was placed into an enucleated egg cell (an egg cell from which the nucleus had been removed) in the lab
a small jolt of electricity was applied to fuse the nucleus and the egg cell together
the egg cell started dividing by mitosis
when several cycles of cell division had formed an embryo it was placed into the uterus of a surrogate mother
where it continued to grow and divide in a normal way until birth
What is a transgenic organism?
A transgenic animal is one which contains genes from another species
Why is Cloning better than Genetic Modification?
Takes Less Time
Understand why simple, unicellular organisms can rely on diffusion for movement of substances in and out of the cell
Single celled (unicellular) organisms can get their supplies of oxygen and food nutrients by diffusion through the membrane of their cell which is in direct contact with the outside
Because they are so small, it doesn’t take too long to pass the substances through the cell membrane and into the cell
We say they have a large surface area to volume ratio and therefore they do not require a specialised transport system to supply the cell and remove waste products
Structures of the Bacterium?
SEE A DIAGRAM
Immune System Protective Response>
- kill/destro bacteria / eq;
- whi blood cells;
- ph ocytes / macrophage;
- engul / surround / ingest / digest / eat / eq;
- lymp cytes;
- antibodies / anti xins;
- (b d to) antigens;
- mory cells;
Source of ADH?
Hypothalamus
controls water level
Source of Oestrogen?
Ovary
Why do cells not store glucose?
Soluble
Osmotic Effect
Do Bacteria have a cell wall?
Yes
Do Fungi have a cell wall?
Yes
Nervous System Response?
receptor / nerve ending; sensory neurone / sensory nerve; impulse / message / signal; CNS / spinal cord / grey matter; synapse; relay neurone / relay nerve; motor neurone ; muscle / effector; contract;
How does being large help organisms to survive at low temperature?
Small SA:V
Less Heat Loss
How do the structure of Arteries compare to Veins
thick(er) wall;
more elastic (tissue);
more muscle (tissue);
smaller lumen / hole / less space / less
single layer of cells / eq
Why does blood flow in a leg vein slow when there is a lac of movement
(less/no) muscle(s);
contraction;
squeeze vein / push blood / eq;
What molecule makes plants/algae look green?
Chlorophyll
Natural Selection question?
1 variation / variety;
2 rare / random;
3 mutation / mutant;
4 gene / allele / DNA / eq;
5 survive / not killed / live / eq;
6 reproduce / breed / have offspring / eq;
7 pass on (gene) / eq;
8 many generations / repeated over time / eq;
Things to Bear in Mind in Transpiration Practical?
Dry Leaves
Mention Time Taken
Mention How bubble is introduced
Describe how White Blood Cells are used by the Body to defend against infection
1 ingest / engulf / surround / phagocytosis / eq; 2 enzymes; 3 digest / breakdown / eq; 4 lymphocytes; 5 antibodies / antitoxins; 6 specific / eq; 7 antigen: 8 memory / memory cell / eq;
Genetic Engineering in Animals?
1 human gene / human DNA / human allele; 2 restriction enzyme; 3 plasmid; 4 vector; 5 same restriction enzyme; 6 ligase; 7 recombinant plasmid / recombinant DNA;
Describe how Selective Breeding could be used to increase milk production?
1 cow with high milk yield / eq;
2 male/bull with high milk yield daughters or
high milk yield mother / eq;
3 reproduce / mate / breed / AI / eq;
4 repeat process with high milk yield offspring /
many generations / eq;
What factors could be kept the same when testing plants?
same temperature
light intensity
CO2
water
humidity
minerals
nutrients
soil
Diagram of a Phagocyte?
SEEGOOGLE
How to clone animals like Dolly the Sheep?
nucleus from body cell / nucleus from adult cell /
nucleus from adult / eq;
egg / ovum;
remove nucleus (from egg) / enucleate (from egg);
nucleus into (empty) egg cell;
electricity;
mitosis;
embryo;
uterus / womb;
surrogate (mother);
Explain how the structure of blood vessels entering and leaving the glomerulus help to move glucose into the Bowman’s capsule?
vessel entering is wider / eq;
(increased) pressure;
ultrafiltration;
What type of Blood vessels are found in the glomerolus?
Capillaries
How to investigate the effect of exercise on humans?
Range of Excercies
Count Breathes
For a certain amount of time
Jog for 5 minutes
Repeat
Explain why milk must be cooled to 46c’ during the production of yoghurt?
1 avoid killing Lactobacillus / bacteria /
organisms (that make yoghurt);
2 optimum temperature;
3 enzymes;
4 (enzymes) denatured / destroyed;
Homozygous?
same alleles
How to work out the surface area of a cube?
A=6a2
Factors affecting the rate of Diffusion?
Temperature
Concentration
Surface Area
Gradient
Osmosis?
Movement of water particles from a dilute to more concentrated solution through a partially permeable membrane
Why may Osmosis increase the mass of a cube?
Water Enters
From Dilute to Concentrated Solution
Through a Partially Permeable Membrane
Why would Red Blood Cells not be seen if they are placed in distilled water under a microscope?
Water into a Red Blood Cell
Cells burst
No Cell Wall
Why may the volume of a solution not be accurate?
Parallax Error
Evaporation from the cup
How and Why is Glucose reabsorbed from the nephron back into the blood?
Active Transport
Low to High concentration
Energy in the form of ATP
It is needed for Respiration to produce energy
It uses an Osmotic Effect
Why do plants lose their leaves in cooler months?
Reduced Water Loss
Less Light –> Less Photosynthesis –> Conserves Energy
Difference between Egestion and Excretion?
Undigested Versus Metabolic Waste Product
Why is the transplanted Kidney placed in the lower abdomen instead of in the kidney’s usual location?
Nearer to Bladder
Easier Access
Which Mineral ion in Meat is needed to make Haemoglobin?
Iron
How does Lactic Acid affect the Body?
Lactic Acid ==> Low pH ==> Affects Enzymes ==> Lowers the Rate of Reaction ==> Less Energy Supplied
Explain how tearing meat into smaller pieces helps digestion in the stomach?
Increases SA
Increases SA:V
Ingestion?
food enters the mouth
Assimilation?
small food molecules
are used to build large
molecules
Uses of Fats?
Protection
Insulation
Cell Membranes
Energy
Root Hair Cells Diagram?
See
Two changes to the blood when it passes through the lungs?
It becomes Oxygenated
Loss of Co2
Do WBC’s contain a Nucleus’?
No, they do not contain Nuclues’
Why do Sprint Athletes gain no advantage from training at high altitudes
short race / quick race / short time / short
distance / eq;
oxygen not needed / no need to breathe / eq;
anaerobic respiration;
Role of Stomata in Transport in Plants?
Diffusion
Creates Transpiration Stream
Osmosis
Why do Cyclists and Runners have lower heart rates than the average person?
Heart is Larger
Due to Excercise
Pumps more blood in each beat
Provides More O2
More Aerobic Respiration
Why may a Long Distance Athlete who trains at high altitudes have a better chance of winning than a long-distance athlete who trains at sea level?
More Red Blood Cells
More O2
More Respiration
More Energy
Less Lactic Acid
Which Valve belongs to the Right Side of the Heart?
Tricuspid
R FOR RIGHT (DDDDDDDDDDDDDD)
Why do students obtain blood samples from a vein rather than from an artery?
Lower Pressure
Thinner Wall
Why can students not contain blood samples from capillaries?
Small
Suggest what happens in heart muscles when the coronary artery is blocked?
Less O2
Less Glucose
Less Aerobic Respiration –> Less Anaerobic Respiration
Produces Lactic Acid
Low pH
Inhibits Enzymes
How does an increase in the concentration of O2 affect gas exchange?
Increase in levels of O2
Increase in rate of diffusion
Why is a leaf pushed to the bottom of a boiling tube and covered with ethanol in a photosynthesis experiment?
To remove Chlorophyll?
Describe a Test to prove that Light is needed for Photosynthesis?
Place one leaf in light
Place one leaf in dark
Test for Starch (Iodine Solution)
The leaf in light will test positively for starch as photosynthesis occurs.
Photosynthesis produces Glucose which is a monomer of starch
Describe a Test to show how Chlorophyll is needed for Photosynthesis?
1.) use variegated leaf / eq;
- draw pattern of chlorophyll and compare results
/ test white and green parts / eq;
3.) Test for Starch
Describe a Test to show how Co2 is needed for Photosynthesis?
Add NaOH
Remove Carbon Dioxide
Test for Starch
Explain how very high temperatures might reduce the growth of plants?
- ss photosynthesis;
- (more) transpiration / evaporation /
loss of water / eq; - stomata close / less mineral ion transport;
- less carbon dioxide uptake;
- enzymes denature /
change in shape of active site / eq;
Structure of a Leaf?
See
Why is there a difference in the average rate of photosynthesis between blue light and green light?
- blue light absorbed;
2. green light reflected / transmitted / not absorbed / eq;
What are blood cells transported in?
Plasma
Can Yeast be used in the production of beer?
Yes
Meaning of Antibiotics?
Kills/ Remove Bacteria
Are all Virus’ pathogens?
Yes, all Virus’ are pathogens
Differences between Viruses and other living organisms?
Viruses are smaller
Viruses contain a protein coat
Viruses have no organelles
What type of organism bacteria?
Bacterium
PENICILLIUM
Are Fungi Multicellular or Single Celled?
Some are multicellular and Some are Single Celled
The molecule used to store carbohydrate in fungi
Glycogen
How does Chewing aid digestion?
Increases Surface Area
Enzymes
For digestion
Which Vessel contains the least Co2?
Pulmonary Vein
Which Vessel contains the least urea?
Renal Vein
Which Vessel contains the highest Blood Pressure?
Aorta
Diagram of Capillaries, Arteries and Veins?
See
How to test for leaves in starch?
place leaf in boiling water (1)
• boil / heat in ethanol (1)
• use water bath / switch off Bunsen / keep away
from Bunsen / eq (1)
• wear safety glasses / use tongs / forceps / eq (1)
• add iodine solution (1)
• if starch present goes blue/black / see if it goes
blue / black (1)H
Why do plants store carbohydrate as glucose>
Glucose is soluble so no Osmotic Effect
Explain why a mouse uses more Oxygen per gram than a human?
mouse is smaller / less body mass (1)
• larger surface area to volume ratio (1)
• heat loss / eq (1)
• maintain body temperature (1)
• (more) respiration / higher metabolic rate (1)
Explain how the structure of the heart of a frog means that it is unable to move for long periods of time?
one ventricle (1)
• oxygenated and deoxygenated blood mixes / blood
from body mixes with blood from lung / eq (1)
• less deoxygenated blood goes to lungs / some
oxygenated blood to lungs / eq (1)
• less efficient gas exchange in lungs / eq (1)
• no semi-lunar valves (1)
• backflow of blood into ventricle (1)
• less oxygenated blood to body / some
deoxygenated blood to body / less oxygen (to body)
/ eq (1)
• less respiration / more anaerobic respiration (1)
• lactic acid accumulation / less ATP made / less
energy released (1)
Describe the function of plasma in transporting named substances in the body?
glucose (transported) from intestine / ileum / liver /
glucose (transported) to body cells / to liver (1)
• amino acids (transported) from ileum / liver / amino acids
(transported) to body cells / liver (1)
• fatty acids / vitamins / minerals / eq (transported) from
intestine / fatty acids / vitamins / minerals / eq
(transported) to cells (1)
• hormones (transported) from (endocrine) glands /
hormones (transported) to organs / tissues (1)
• urea (transported) from liver / urea (transported) to
kidney (1)
• carbon dioxide (transported) from cells / carbon dioxide
(transported) to lungs (1)
• antibodies (transported) to site of infection / eq (1)
• fibrinogen / clotting proteins (transported) to wound /
eq (1)
Why does Chewing help digestion?
Increases SA
Enzymes
Give two ways in which RBC’s and WBC’s differ?
red cells smaller (1)
• red cells have no nucleus (1)
• red cells are biconcave /eq (1)
Describe the differences between diffusion and active transport.
diffusion passive (1)
• diffusion from high concentration to low /
requires concentration gradient (1)
• active transport requires ATP / energy/ oxygen
/ respiration (1)
• active transport requires membrane / carrier
proteins (1)
• diffusion can take place in non-living systems
(1)
Describe the differences between active transport and diffusion?
temperature increases (kinetic) energy / particle movement / more collisions / eq (1)
• difference in concentration / concentration
gradient increases rate of movement (1)
• short(er) distance increases diffusion /eq (1)
• surface area to (volume ratio) increases
diffusion (1)
• mass / size of particle smaller particles move
faster (1)
• larger particles / charged particles cannot
pass through cell membrane (1)
• (increased) oxygen / ATP / respiration /
energy for active transport (1)
Why does the person keep breathing after the exercise?
(supply (more)) oxygen / there was a shortage of oxygen (1) • breakdown / remove lactic acid (1) • repay oxygen debt (1) • anaerobic respiration had occurred (1)
Why do woman require more dietary requirments?
calcium for bone / teeth growth / bone / teeth
development / prevent rickets (1)
• protein to grow / for enzymes / antibodies /
eq (1)
• iron for haemoglobin / red blood cells / prevent anaemia (1)
• vitamin D for bone growth / bone
development / calcium absorption / strong
bones (1)
• more energy as baby is heavy / mother
becomes heavy / more energy for fetal
development / to carry baby / eq (1)
Describe the role of the stomach?
protease / pepsin / peptidase (1) • digest / breaks down protein (1) • hydrochloric acid (1) • kill pathogens / eq / optimum pH ignore germs (1) • churning/ mechanical digestion (1)
