Exam Questions Flashcards
Why do animals have horns?
For defence
What is meant by natural selection?
Survival of the fittest
Which then go on and breed
Describe two trends in evolution of the human skeleton
Increase in height
Shorter arms
Why did people disagree with Darwin?
Religious objection
Insufficient evidence
Give one way in which Darwin’s theory differed from Lamarck’s
Darwin’s theory depends on differences in genes at birth
Give one way a student could obtain more accurate results
Sample a great height
What is the main purpose of pre-clinical testing?
Testing for toxicity
In phase 1 of the clinical testing, very low dose of the new drug are uses on a small number of volunteers. What is the main purpose of Phrase 1 testing?
Testing for side effects
In phase 1 testing, healthy volunteers are used rather than patients, why?
Might conflict with patient’s treatment
What is the main purpose for phrase 2 and 3 testing?
To find the optimum dose
What is meant by a placebo?
A tablet that does not contain the tested drug
During the testing of a drug, who knows patients are receiving?
Neither patients not doctor
What is meant by metabolic rate?
Rate of chemical reactions in cells
Cholesterol is carried around the body by the two types of lipoprotein: low-density lipoproteins (LDLs) and high-density lipoproteins (HDLs ). Describe the relationship between the two types of lipoproteins and heart health
LDL causes heart disease
HDL helps prevent heart disease
Balance important for good heart health
How do viruses cause illness?
Reproduce in cell
Why may a group of people (Indians)get a disease and another not (TV crew)?
They may be immune
They crew had previous exposure to flu
Indians caught disease form the TV crew
Name the gland which:
FSH
Pituitary
Name the gland which:
Oestrogen
Ovary
What proportion of a 28 day menstrual cycle is the fertile period?
25%
A woman does not usually become pregnant after intercourse on day 9. However, she may become pregnant after intercourse on day 17 of the cycle. Suggest an explanation for this
Day 17 infertile period
Day 9 sperm dies before reaching the egg
Which structure in the Nucleus contains 99.5% of a cell’s genitc information?
Chromosomes
Evaluate how the production of rabbit-human embryo may help research into human diseases
Pros:
Overcomes shortage if human eggs
Reduces test in adult humans
Cons
Ethical issues of experimenting with rabbits
Religious objections to killing embryos
What does a thick coat do?
Reduces heat loss
Who is a seal adapted to swim?
Streamlined
Flippers
Powerful tail
Swim in cold conditions:
Fat-insulates
Large mass to area ratio - heat loss reduced
Name the piece of apparatus used in sampling a 1m2 piece of land
Quadrat
Describe how a quadrate is used
Use a transect
Sample every meter
Count plants in quadrate
What is meant by pandemic?
Worldwide
Explain why a new mutation of the influenza virus might cause another influenza pandemic
New strain of flu
Vaccination not effective
People not immune
People travel between countries spreading infection
Suggest two reasons for the difference in the number of deaths from heart disease in men and women between the ages of 40-60
Men smoke more
Genetic factors
Give three main stages in testing a new drug before it is sold
Laboratory tests
Tests for side effects on volunteers
Testing for optimum dose
Explain what is meant by a clone
Genetically identical
Describe how the process of adult cell cloning could be used to clone a frozen mouse
Remove the nucleus of the egg
Insert genetic material from frozen mouse
Electric shock
Most people would be opposed to cloning a human from a dee-frozen, londpg-dead relative, why?
Not know if it is safe
Explain why flamencos have long legs terms of:
Darwin’s theory
Mutation
Ones with longer legs could feed in deeper water
Survive and reproduced
Explain why flamencos have long legs terms of:
Lamarck’s theory
Flamingos stretch their lungs to be able to feed in deeper water
Longer legs inherited by offspring
Name two hormones that stimulates the ovaries
FSH and LH
What is sexual reproduction?
Fusion of gametes and sperm
A sores has characteristics of a zebra and a horse, why?
Mixture of genes from both parents
Describe how Aleut cell cloning could be used to clone a horse
Skin cell from zorse Unfertilised egg cell from horse Remove nucleus from the egg cell Take nucleus from skin cell Then give electric shock Causing the cell to divide Then place embryo in womb
Other than measles which two diseases does the MMR vaccine protect against?
Mumps
Rubella
Describe what happens in the body after immunisation to stop a person catching measles in the future
White blood cell
Produces antibodies
If reinfected antibodies production will be faster
The biomass in the five ladybirds than the biomass in the bean plant, why?
Not all digested
Not all eaten
Loss of carbon dioxide
Loss in urine
The carbon in dead bean plants is returned to the atmosphere via the carbon cycle. Describe this part of the carbon cycle
Microorganisms breakdown bean plant
Respiration of microorganism release carbon dioxide
What is a hormone?
Chemicals that control body functions
Name an organ that fro duces a hormone
Glands
How are hormones transported?
In the blood
Describe how the function of hormones FSH, oestrogen and LH are involved in the control of the me steal cycle
FSH stimulates oestrogen production
Oestrogen inhibits FSH
LH stimulates egg release
What scientific term describes a change in a gene?
Mutation
What is the true tested on in lavatories before clinic trials?
Cells
Tissues
animals
Drugs must be trialled before the drug can be used on patients, why?
To test for: Toxicity Interaction with other drugs efficientcy Dosage
The receptor in a leg muscle in a leg is sensitive to a stimulus, suggest which one
Stretch
Describe what happens at the synapse during the reflex of a leg
Chemical released
Diffuses across synapse
Transmits impulse between neurons
What type of food chain provides the largest biomass and energy and why?
The shortest chain
Because less loss in waste and respiration
Describe how are animals adapted to survive in dry conditions
Decrease in surface area - reduces area from which waste may be loss
Fat in hump to convert water via respiration
Long lashes to keep dust put of their eyes
Describe how are plants adapted to survive in dry conditions
Reduce surface area - reduces waste loss
Wide spread roots to absorb more water
Fleshy / thick stem to store water
The dead plants in a nest decay. The decay process helps to keep the eggs warm, how?
Microorganism respire
Respiration releases energy
Megapode birds open and close the air vent of their nest at different time of the day, why?
Allows oxygen in
Oxygen needed for respiration
Allows release of carbon dioxide
Suggests one advantage of the population as a whole of children having the second MMR vaccination
Less change of spread of disease
What does a vaccine contain?
Dead or inactive pathogens
Explain how vaccines prevent infection
White blood cells produce antibodies
Antibodies produced rapidly
These antibodies kill pathogens
Explain why antibiotics cannot be used to treat measles
Antibiotics don’t kill viruses because measles virus live inside cells
Why do antibiotics become less useful at treating an infection of the
Antibiotic is overused?
Pathogens develop resistance to antibiotics
Describe how information passes from the relay neurone to the motor neuron
Release of chemical from relay neuron
Chemical crosses synapse
Chemical attaches to motor causing an impulse
What was the drug thalidomide originally developed to treat?
As a sleeping pill
Soon after it was developed, thalidomide was found to be useful in treating another condition, what was this?
Morning sickness
Describe the harmful effect of thalidomide
Limb defects
Suggest why the harmful effect of thalidomide had not been detected during clinical trials
Drugs not tested on pregnant people
What happen in the body to make someone dependant on drugs?
Changes the chemical process
Suggest one piece of information about legal drugs that would need to be considered before the classification if these drugs change
The harm it does
In the 1800s, many scientists could not decide whether Lamarck’s theory or Darwin’s theory was right, why?
Insufficient evidence
Mechanism of hip hesitance not known
Before the 1800s, many people had a difficult idea to explain where all the living things on Earth came from, what was this idea?
God made all living things
Describe how scientist can transfer the gene form Bacillus thuringiensis to maize plant
Gene cut out from bacterial DNA
gene sliced into maize DNA
Gene added at an early stage of development
Pros and cons of GM maize
Pros: Less effort from farmers Pesticides always there Less insects to eat crops So greater crop production
Cons:
Kills other insects
So some crops don’t get polluted
Possible harm when eaten by humans or animals
Painkillers do not cure infectious diseases, why?
They don’t kill pathogens
In the carbon cycle what is the process from:
Microorganisms to the atmosphere
Fossils to the atmosphere
Respiration
Combustion
Describe the part played by algae in the carbon cycle
Photosynthesis
release carbon dioxide
Eaten by animals
Fed on microorganisms
I tropical rain forests respiration from microorganism is much faster than in most habitats, why?
Moist
Warm
A lot of microorganism
A lot of material to decay
Describe how plants and animals have adapted to reduce the risk of beinging eaten by predators
Camouflage Warning colours Thorns Long ears Poisons
In a plant:
Where is the detection of light stimulus
Where in the shoot doe a the response of light take place
Detection in tip
Response behind tip
Which part of the vaccine stimulates the body’s defence system?
Inactive pathogens
After an injection why does the person not get the disease after coming in contact with it?
White blood cells produced
Antibodies produced quickly
These antibodies destroy the pathogen
Why may a new strain spread rapidly?
Antibiotics ineffective to resistant pathogens which survived. These pathogens would reproduce. The population of resistant pathogens increase
Describe how scientists produce the genetically modified zebra fish
Jellyfish genes cut out
Gene transferred to zebra fish at early stages of development
Enzymes used to help this process
Some scientist are worried about the production genetically modified zebra fish, why
Effect the food chain
Effects on the zebra fish themselves, e.g. May out compete non-GM zebra fish
Explain the advantages of a tree having:
Shallow root spread out over a large area
Increased water uptake after rain
Explain the advantages of a tree having:
Large, bulb-like roots deep in the soil
Water storage
Explain why some desert plants have leaves which are covered with a layer if wax and fold together during the day
Reduced water lose
Wax protects plants
Folding reduces surface area
Name to hormones in IVF
FSH
LH
Describe the process of IVF
Eggs collected from ovary Eggs mixed with sperm Fertilised egg divides Embryo formed Embryos inserted into womb FSH matures egg and LH releases egg
Why are hand-gels placed at the entrance of a hospital?
Kills bacteria and reduces transfer of illnesses
Explain as full as you can how MRSA strains become difficult to treat
Mutation causes resistance to antibiotics
Name two diseases linked to obesity (not including cancer)
Arthritis
Diabetes
High blood pressure
Why does an increase in exercise help a person lose weight?
Increase metabolic rate exercise needs energy so fat is used
What happens to people’s body when they become dependent on a drug?
Drugs alter chemical process in the body
They person suffers from withdrawal sump toms with out the drug
Why is the effect of alcohol much more than the effect of heroine?
Many more people use alcohol
Less harmful effect multiplied
Pros and cons of adult cloning to conserve endangered species
Pros:
Useful in species difficult to breed
Prevents extinction
Cons:
Development problems
Cloning reduce
S gene pool
