Biology paper 1 (complete) Flashcards
B4: Write down the word equation for photosynthesis.
Carbon dioxide + Water –> Oxygen + Glucose
B4: symbol equation for photosynthese
6C02 + 6H20 –>
C6H12O6 + 6O2
B4 ; Photosynthesis is affected by limiting factors.
What is meant by the term ‘limiting factor’?
A factor which is not at an optimum level to enable maximum rate
of photosynthesis e.g. temperature
B4 : Name the raw materials needed by a plant for photosynthesis?
Carbon dioxide and water
B4: Name the green pigment present in plant cells.
What is the role of this green pigment?
Chlorophyll.
To transfer energy from the environment and use it to synthesise glucose from carbon dioxide and water.
B4: List three ways commercial farmers improve the environmental conditions in large greenhouses to maximise photosynthesis and ensure they make a profit.
Increase the air temperature with heaters.
Provide artificial lighting to supplement the sunlight and through the night.
Increase the amount of carbon dioxide in the atmosphere.
B4 :List three ways glucose produced by photosynthesis is used in plants?
Used for respiration; used to produce fats or oils for storage; used to produce amino acids for protein synthesis; converted into insoluble starch for storage; used to produce cellulose to strengthen cell walls.
B4: Light intensity formula
Light Intensity α 1/ distance2
B4: When does respiration occur in cells?
Continuously
B4: Aerobic respiration
needs oxygen
end products: carbon dioxide + water
oxidation of glucose is complete
efficiency of energy is high
B4: Anaerobic respiration in animal cells
does not need oxygen
end products: lactic acid
oxidation of glucose is =incomplet
efficiency of energy is low
B4: Anaerobic respiration in plant and yeast cells
oxygen?
end products?
oxidation of glucose?
efficiency?
does not need oxygen
end products: lactic ethanol and carbon dioxide
oxidation of glucose is IncompletE
efficiency of energy is low
B4: Name three processes that organisms require energy for.
Chemical reactions to build larger molecules, keeping warm and movement.
B4: What does the chemical formula C6H12O6 represent?
Glucose
B4: rite down the word equation for aerobic respiration in a plant cel
glucose + oxygen carbon dioxide + water
B4: Write down the word equation for anaerobic respiration in a yeast cell.
glucose –> carbon dioxide + ethanol
B4: Why is fermentation of economic importance?
Used in the manufacture of bread and alcoholic drinks.
B4: Describe three ways in which the body responds to vigorous exercise in order to ensure sufficient oxygen reaches the muscle cells.
Increase in heart rate; increase in breathing rate and increase in breath volume.
B4: If exercise carries on for a long time, what happens to the muscles?
Muscles become fatigued and stop contracting efficiently.
B4: Why is respiration described as an exothermic reaction?
Respiration is an exothermic reaction because it transfers energy to the environment.
What is the definition of metabolism?
Metabolism is the sum of all reactions which occur in a cell or body.
What are the following made from:
a) carbohydrates
b) lipids
c) proteins
a) many glucose molecules
b) 1 molecule of glycerol and 3 molecules of fatty acid
c) many amino acids
Describe the process for removing lactic acid from the body.
Blood flows through the muscle cells and transports the lactic acid
to the liver where it is converted back into glucose. The glucose is
then used in aerobic respiration or stored as glycogen
B4: What is meant by the oxygen debt?
The amount of extra oxygen which is needed to remove all lactic
acid from the body is known as the oxygen debt.
B3: What is the definition of a pathogen?
Micro-organisms which cause infectious disease in animals & plants.
List four types of micro-organism which can act as pathogens.
Bacteria, Virus, Protist, Fungus.
What do pathogens need from the host organism?
Suitable conditions and nutrition to be able to grow and reproduce.
How can HIV be controlled
HIV can be successfully controlled with antiretroviral drugs. If the
immune system is badly damaged then AIDS may develop.
Measles symptom method of transmission control spread by caused by
Measles
Fever
Red skin rash
Droplet infection
from sneezes and
coughs
Child Vaccination
Virus
Salmonella symptom method of transmission control spread by caused by
Fever, cramp,
vomiting, diarrhoea
Food prepared in
unhygienic
conditions or not
cooked properly
Improve food hygiene, wash
hands, vaccinate poultry,
cook food thoroughly
Bacteria
rose black spot symptom method of transmission control spread by caused by
Purple black spots
on leaves
Spores carried
via wind/water
Remove infected leaves and spray
with pesticide
Fungus
gonorrhoea symptom method of transmission control spread by caused by
Green discharge
from penis or
vagina
Direct sexual contact
or body fluids
Use of a condom and treat
infected person with antibiotics
Bacteria
malaria symptom method of transmission control spread by caused by
Recurrent fever By a vector from an
infected person
Preventing breeding of mosquitoes
or use of a net to prevent being
bitten
Protist
TMV symptom method of transmission control spread by caused by
Mosaic pattern on
leaves
wounds in
epidermis caused
by pests
Remove infected leaves and
control pests which are
damaging leaves
Virus
Suggest how pathogens could be transferred in this situation.
What could people do to reduce the spread of pathogens?
Direct contact by
touching a
contaminated
surface.
Droplet infection if someone sneezes or coughs in the lift. Air - if fungal spores are present.
Could reduce the spread by: Hand over mouth if coughing and then washing.
Use a tissue if sneezing and then dispose of it and wash hands. Washing hands with soap after visiting the
toilet.
Wear a face mask.
Name and describe 3 ways the human body defends against the
entry of pathogens.
Skin – barrier, nose - nasal hairs , mucus and cilia,
trachea & bronchi – mucus to catch, cilia to remove from lungs,
stomach - HCl acid kills.
What is an antigen?
A protein on the surface of a pathogen.
Why will the antibody produced for measles not be effective in other
diseases?
Antibody has a specific shape which fits with a specific
antigen.
Why are dead or inactive pathogens used in a vaccine?
To stimulate white blood cells to make antibodies without causing the
disease.
What happens if the live pathogen invades the body after being
vaccinated?
White blood cells able to respond much faster and produce more
antibodies quicker to destroy the pathogens so the person doesn’t
suffer the symptoms of the disease.
What is an antibiotic and what is it used for?
Kills bacteria inside the body without harming human cells.
Why is there a growing concern about bacterial resistance to
antibiotics?
The resistant bacteria are not killed and can continue to
multiply inside the body making the person very ill and infecting
others too.
Which one of these statements is true?
Painkillers are used to treat the symptoms of a disease and kill the
pathogens which cause it
Painkillers are used to kill the pathogens causing a disease
Painkillers are used to treat the symptoms of a disease but do not kill
the pathogens.
Any potential new drug has to go through a series of tests. What is meant by the following terms? a) efficacy b) toxicity c) optimum dose
a) Efficacy how effective the drug is
b) Toxicity how poisonous the drug is
c) Optimum dose minimum amount of the drug which provides
the best response
the process of drug testing.
- Drugs are trialled in laboratories on cells and tissue cultures
- Drugs are trialled on live animals
- Drugs are trialled on healthy volunteers
- Drugs are trialled on people with the disease the drug is for
What is a placebo and why is it used?
A medicine that does not contain the drug that is being trialled.
A placebo is used to check that there are no other factors which
may cause the patient‘s condition to improve without the drug.
how monoclonal antibodies are produced.
- Mouse is injected with a pathogen.
- Mouse lymphocytes produce antibodies.
- Mouse lymphocytes are collected.
- Mouse lymphocyte and mouse tumour cell are fused.
- Hybridoma cells are separated and cultured to form a clone.
- The clone produces large quantities of antibody.
- The antibodies are collected and purified.
What are the applications of monoclonal antibodies?
Pregnancy testing
Used to measure levels of hormones and other chemicals in blood
Treat some cancers by delivering a toxic drug to the cancer cells
To find various molecules in cells or tissues by binding to them with a
fluorescent dye
Why do some people feel the use of monoclonal antibodies is unethical?
Mouse has to suffer the disease deliberately
Mouse is induced to have cancer
Treatment not always safe
It’s very expensive and money could be better used
Name 3 ways you can detect that a plant is diseased.
leaf spots/discolouration, growths, malformed stems or leaves, presence of pests,
stunted growth, areas of decay (rot)
Type of plant defence used
what is the plant being defended against
describe the defence being used
Mechanical
Herbivores eating it Thorns or hairs
Chemical Pathogens/bacteria
Herbivores/animals
The chemical released is
antibacterial or poisonous
Physical
Herbivores and
pathogen entry
Dead bark coating which falls off
Physical Insects such as aphids Waxy cuticle/cellulose cell walls are hard to penetrate
Describe why nitrate ions are very important for plants.
Nitrate is crucial for protein synthesis and hence growth. Without
sufficient nitrate ions, the plant would be stunted.
What is chlorosis and how can it be prevented?
Chlorosis is the yellowing of the leaves. It can be prevented by
providing the plant with magnesium.
B3: Why would a test kit containing monoclonal antibodies be useful to
detect plant disease?
The monoclonal antibodies can be used to detect a particular
chemical which is only present in one type of pathogen. This would
then show whether the plant was infected with this disease or not.
B2: Put the following in order of size from the smallest to the largest:
organ organism cell tissue organ system
cell tissue organ organ system organism
B2: Define each of the words:
a) organism
b) organ system
c) organ
d) tissue
e) cell
Organism - A group of organ systems working together.
Organ system - A group of organs working together to perform a
specific function.
Organ - A group of tissues working together to perform a specific
function.
Tissue - A group of similar cells with a similar structure and function.
Cell - The smallest structural and functional unit of an organism.
B2: What is digestion?
Large insoluble molecules are broken down into
smaller soluble ones.
B2: What is an enzyme?
A biological catalyst – they speed up the rate of
reaction without being used up.
Amylase
Produced in
Salivary glands and
pancreas
Breaks carbohydrates into simple sugars
Protease
produced in Stomach and
pancreas
breaks proteins into amino acids
lipase
produced in pancreas
breaks Fats and oils (lipids) into fatty acids and glycerol
What biological molecule are enzymes made of?
proteins
What is the active site of an enzyme?
It is where the substrate binds.
What is a substrate?
Substance (chemical) that the enzyme acts on.
What are the products of digestion used for in the body?
They are used
to build new carbohydrates, lipids and proteins in the body. Glucose is
used in respiration.
What does denatured mean?
That the active site of the enzyme has
changed shape so the substrate cannot fit.
How does increasing the temperature affect enzyme activity?
Initially it
increases the rate of reaction due to increased collisions between the
enzyme and substrates, if the temperature is too high the enzyme will
denature.
How does pH affect enzyme activity?
Enzymes have optimum pH
conditions, if these are too alkaline or acidic the enzyme denatures
What is the role of bile in digestion?
It neutralises stomach.
(hydrochloric) acid and emulsifies fats.
Where in the body is bile made?
Bile is made in the liver and stored
in the gall bladder.
What is a double circulatory system?
Where blood from the heart is
pumped to the lungs and the body at the same time.