PAPER 2 Flashcards
Describe how the blood in the left side of the heart differs from the blood in the right side of the heart. (2)
- (more) oxygen / oxygenated
- (less) carbon dioxide
- high(er) pressure
Suggest what is meant by the term intraventricular (1)
- in ventricle
A - Conjunctiva
B - Lens
C - Cilary Muscle
Explain the changes that take place in the pupil and the cilary muscle when a person focuses on a nearby object. (2)
- lens gets fatter
- ciliary muscle contract
Describe one reflex action that occurs in the eye. (2)
- (in bright light)
- pupil constricts
Give a reason for the lens changing in bright light (1)
- Lets less light into the eye
- Prevents damage
Describe how micropropagation (tissue culture) can be used to produce large quantities of identical plants. (6)
- explant
- small pieces of plant
- agar jelly
- nutrient medium
- sterile
- growth hormone
- control moisture
- clones
- all year round
Explain what is meant by the term genetic modification (GM) and suggest why a farmer might want to grow a GM crop. (3)
- transfer of gene
- using vectors and plasmids
- resistant to pests/disease
Describe the advantages to the human body of producing memory cells. (2)
- antibody production faster
- respond to infections
Describe how you would carry out an experiment to find out the energy value of a potato crisp. (4)
- weigh crisp
- burn crisp
- burnt completely
- hold (burning crisp) under tube
- volume of water
- measure temperature before and after, find temp change
Name the enzyme that cuts DNA. (1)
Name the enzyme that joins DNA. (1)
Name a vector. (1)
- Restriction
- Ligase
- Plasmid
What is meant by the term transgenic? (1)
- allele from different species
Describe how the process of nitrification affects the availability of nitrates to plants. (2)
- (nitrifying) bacteria
- nitrite into nitrate
Describe the biological consequences of cigarette smoking on the human lungs. (5)
- emphysema
- damage to alveoli
- bronchitis
- infection;
- cilia damaged
- build up of mucus
- carcinogens
- tar
Suggest the benefits of producing transgenic hearts. (3)
- transplant
- (more) hearts available
- less immune response
- less deaths
Explain what is meant by the term gene (2)
- DNA
- Codes for a protein
Explain how temperature is controlled in the fermenter. (2)
- temperature recorder
- cooling jacket
Explain the purpose of the paddles in the fermenter. (2)
- distributing oxygen for respiration
- distributing nutrientsfor growth
- distributing heat
Other than temperature, name one condition that needs to be controlled in a fermenter and state why it needs to be controlled. (2)
- pH
- optimum condition for enzymes
Describe how the developing embryo is supplied with nutrients. (3)
- placenta
- from mother’s blood; diffusion / high conc. to low conc
- large surface area
- umbilical cord;
Explain how the rate of sweating of a person at rest is affected if that person is in hot air. (2)
- more sweat
- maintain body temperature
Explain how the rate of sweating of a person at rest is affected if that person is in air with a high humidity. (2)
- less evaporation
- sweat can not disperse
- cannot cool
- overheating
- more sweat;
Limewater is an indicator that can be used to show an increase in the level of carbon dioxide.
Suggest why it would not be a suitable indicator for use in some investigations. (1)
- Cannot show amount of CO2
Describe the changes that would take place in the eye of a pigeon to help it focus on an approaching hawk. (4)
- ciliary muscle contracts
- suspensory ligaments slacken / relax
- lens becomes fat(ter) / thick(er) / wider / rounder
Describe what happens to protein from pigeon meat when it is in a hawk’s stomach. (3)
- large to small molecules
- protease enzyme
- made into amino acids
- HCl / acid / low pH;
What is meant by the term dominant allele? (1)
- Always expressed
What is meant by the term codominant alleles? (2)
- expressed
- heterozygote
Suggest how a woman could accurately determine her body temperature. (2)
- thermometer
- mouth / ear / armpit
Explain why only about 10% of the energy in the cereal crop is transferred to organisms that eat the crop. (2)
- respiration
- not all eaten
- not all digested;
Explain why temperature must be controlled in the fermenter. (2)
- bcoz respiration produces heat
- enzymes denatured
- optimum condition
- maximum growth
- microorganisms killed
What is another name used to describe a fertilised egg? (1)
- Zygote
Explain why the rate of decomposition is affected by the pH of the soil. (2)
- enzymes
- optimum
- denatured
Explain how nitrate ions help plants to grow. (2)
- amino acids
- protein / DNA
Explain how nitrate ions get into the root cells of plants. (3)
- active transport
- low to high conc against conc. gradient
- requires energy
- root hair (cells) have large surface area
Suggest two other modifications to burning food experiment and explain how it would improve the accuracy of the result. (4)
- lid for less heat loss
- stir for more even temperature
- digital thermometer for precision
Suggest why explants are sterilised (2)
- (kill) bacteria / (kill) pathogens
- prevent disease / prevent infection
- (less) competition (for minerals);
The destruction of habitat can lead to extinction of species. Give three other disadvantages of deforestation. (3)
- eutrophication
- soil erosion
- drought
- (more) CO2 in air / less CO2 removed
- loss of medicinal plants
Describe the biological consequences of pollution of water by sewage. (4)
- (more) bacteria
- more decomposition / decompose(rs)
- more respiration
- (less) oxygen
- fish die / animals die
- mineral ions
- algal bloom
- eutrophication
Sandy soil contains large soil particles with big air spaces between them. Suggest why many plants may find it difficult to grow in sandy soil. (2)
- less water
- (less) anchorage
What is meant by the term homozygous? (1)
same alleles
Describe what is meant by the term excretion. (2)
- removal
- of waste products of cells
Explain the role of structure A. (3)
- release sweat / sweating
- evaporation
- cooling / heat loss
Explain the role of structure B. (3)
- vasodilation
- (more) blood to skin
- cooling
Explain the role of insulin in homeostasis. (2)
- lower blood glucose
- glucose to glycogen
- stored in liver / muscle
Explain the role of ADH in homeostasis. (3)
- control water level
- adjusts permeability of collecting duct
- water reabsorption
- more concentrated urine / less urine
Explain why the milk must be cooled to 46 °C. (2)
- avoid killing Lactobacillus
- optimum temperature
- (enzymes) denatured / destroyed;
Explain why the yoghurt is kept in a warm place for 8 hours. (2)
- (time) to make lactic acid
- (warm) optimum temperature
- for enzymes
- bacteria reproduction
Changes take place to the pH of the yoghurt when it is kept warm for 8 hours. Describe and explain how the change in pH helps to preserve the yoghurt. (3)
- kills bacteria / stop growth of bacteria
- low pH / more acid / acidic / lactic acid
- denatures/destroys enzymes / alters active site
State what is meant by the term antibiotic (1)
- removes bacteria
Describe how the body’s immune system kills bacteria (4)
- white blood cell
- phagocyte
- ingest / engulf / eat
- digest / breakdown / enzymes
- lymphocyte
- antibody / antitoxin
- antigen
Use your knowledge of natural selection to explain why there has been an increase in the number of MRSA bacteria (4)
- variation = some resistant / some not resistant
- mutation survive(s)
- reproduces
- pass on gene(s)
Describe how starch is digested in humans. (3)
- salivary gland
- amylase / maltase (ONCE)
- pancreas / small intestine
- maltose / glucose;
Suggest why oxygen gas is passed into the calorimeter. (1)
- Increase combustion
explain what red blood cells would look like in distilled water (2)
- cells burst
- water enters cells
- no cell wall
explain what the red blood cells would look like in concentrated sugar solution (2)
- flaccid
- water leaves cells
Suggest why it is important to introduce air into the fermenter. (2)
- oxygen
- aerobic respiration
- mix
Before being used the empty fermenter is cleaned using steam. Suggest why. (2)
- sterilise / kills microorganisms
- condenses
- prevent competition from unwanted organisms
- prevent chemical contamination of product;
Suggest why the bees collect nectar (2)
- to make honey
- sugar / glucose
- energy / respiration
Name two different groups of organisms that act as decomposers. (2)
- fungi
- bacteria
Describe the changes that take place in the iris when moving into the dark room and explain how they help you to see more clearly. (3)
- radial muscles contract
- pupil dilates
- more light can enter;
Give two nutrients that should be added to the agar medium. Explain how each nutrient helps plant growth. (2)
- nitrate for amino acids
- magnesium for chlorophyll
Suggest how damage to the air sacs can cause the symptom of breathlessness when exercising (2)
- less surface area;
- diffusion / gas exchange;
- (insufficient) oxygen
Explain how the vaccination against Pneumococcus provides protection from further infection (2)
- memory cells;
- antibodies
- (production and response) sooner
Explain how the student could tell whether the seeds had germinated. (2)
- seeds split
- root
- shoot
Explain how a vaccination will protect a human from having an infection. (3)
- inactive pathogen
- memory cells
- antibody;
- soon(er)
Explain how a vaccination will protect a human from having an infection. (3)
- antigen
- memory cells
- antibody production
- soon(er)
Suggest why the rate of sweating changes when a person does exercise, such as running. (4)
- muscles;
- respiration;
- thermal energy produced
- evaporation;
- body temperature falls
Describe how you could use an indicator to show how the exchange of carbon dioxide by a leaf changes in the dark and in the light. (2)
- hydrogen-carbonate (indicator)
- yellow more CO2 / dark
- purple less CO2 / light
Explain why reducing the transport of oxygen to heart muscle cells will make them contract less efficiently and may kill these cells (4)
- less (aerobic) respiration;
- less energy / ATP;
- anaerobic respiration;
- lactic acid;
- low pH / acidic;
- denature enzymes;
Explain how a mammal such as Dolly the sheep has been cloned. (5)
- nucleus (from body cell) put into enucleated egg;
- electricity;
- mitosis / cell division;
- embryo;
- uterus / womb;
- surrogate mother;
Name one useful product that can be made in this fermenter. (1)
- Inulin
Explain why hamsters need to maintain a constant body temperature. (2)
- optimum temperature for enzymes;
Explain what will happen to the muscle cells in the leg if cholesterol builds up in this artery. (5)
- (less) supply of glucose / oxygen;
- (less) aerobic respiration;
- (more) anaerobic respiration;
- less energy / ATP;
- lactic acid / low(er) pH;
- enzymes denature;
- (muscle) cells die / cannot contract;
Explain three conditions needed for seeds to germinate. (6)
- oxygen, respiration
- water to (activate) enzymes
- optimum temperature for enzymes
Describe the role of the placenta in the development of the embryo. (4)
- diffusion;
- glucose / oxygen;
- respiration / energy / ATP;
- amino acids;
- protein synthesis;
- vitamins
- remove carbon dioxide / remove urea;
Where in the eye are the cells that detect the change in the stimulus to cause this response? (1)
- Retina / fovea
Explain the changes that take place in the pupil as a person moves from bright light into a dark room. (3)
- radial muscles contract;
- circular muscles relax;
- pupil gets bigger / wider / dilates / expands
- more light enters eye;
Describe the role of the air supply in a fermenter (2)
- Oxygen
- Aerobic resp
