questions I got wrong

• How can a magnification experiment be improved


  • use thin cells so light passes through the cells more easily
  • use a stain to see parts of the cell
  • use a higher magnification so they are able to be seen more easily
• Devise an experiment to view cells under a microscope

  • use a thin layers of cells
  • use a stain so that cells are more visible
  • place a cover slip on top of the sample - prevents contamination
• state two conclusions/analyse meaning

  • talk about different points on the graph
• give 3 reasons why the three domain classification system was proposed

  • better knowledge of microscopes
  • genetic analysis
  • DNA and RNA sequencing
• Evaluate the advanatges of gm crops

  • advanatages is that they are quick,increase crop yield lessens the need of pestiucides,only targers insects,don't take up space
  • disadvanatages not as effective,worries about them entering the environment and reducing biodiversity,long time consumutions unknown,insects may become resistant
• why do bacteria become resistant to antibiotics

  • people stop taking their medication
  • natural selection occurs due to certain bacteria having mutations in their genes
  • bacteria pass down their mutations by reproducing
• How comes genetic analysis of sequences provide evidence for evolution

  • compare the genes from different organisms
  • closely related organism are similar differences in sequences show evidence for evolution
• nclusions Mendel made about hereditary units

  • can be dominant or recessive
  • determined by hereditary unit
  • each plant received hereditary units from parents
• A scientist wanted to test if prolonged use of a computer affected reaction time. The scientist tested the reaction times of 10 people under the same environmental conditions. These people then used a computer for three hours. The scientist tested their reaction time again. Give three ways that the scientist could improve this method to determine if prolonged use of a computer affects reaction time

  • use more people
  • vary times of day
  • vary usage time
• way of improving general reaction time questions

  • use more people
  • control all other variables
  • repeat on the same people
  • calaculate an average
  • different volume if drink,time if hours
• How are signals transmitted

  • neurones transmitt electrical impulses
  • gap between two electrical impulses is a synapse triggering neurotransmitters
  • neutrotransmitters diffuse across a synapse as a chemical signal
  • bind to the receptors on next neurones
• what happens if neutrotransmitters are prevented

  • prevented from binding to the next neurone so no impulse is triggered and sent to the brain so the person can't feel pain
• Direction of impulse on a neurone

  left to right

  
• ways of improving an experiment

  • more people
  • repeat
  • use a control variable
  • use a control (controlled environment)
• devise a plan to test eye sight with two different eye coloured groups

  • equal amount of people
  • test eyesight
  • see who was shortsighted/longested in each group compare and see hypothesis
• advanatges of eye drops of cataract

  • less visits to a doctor
  • reduces chance of eye infection
• How is cataract treated

  • surgery where a artical lens is implemented
• how can eye sight issueed be fixed

  • glasses
  • optician
  • eyesight tested
• devise a plan the scientist can use to test the effectiveness of a new diet using a drug for 40 people

  • selecto the 40 people
  • half stay on the new diet,half on the old
  • after a fixed period of time reweigh all 40
• what are some factors that the scientist should control when selecting people for a weight loss drug

  • similar exercise
  • similar bmi
  • same gender
• explain why alleles can produce proteins with different structures

  • Dna sequen ces in alleles are different
  • produced in translation
  • mrna strand has a different sequence
  • codes for a different sequence of amino acids and changes function
• why would monoclonal antibodies not react with the blood a person with blood group b

  • the shape of the antibody is complimentary to the a qntigen
  • the antigens in group b have a different shape
  • will only bind to a a
• give two precautions to prevent contamination of an agar jelly plate/aseptic techniques

  • use sterile equipment
  • keep the lid on top of the plate at all times
  • wear gloves
  • work near bunsen burner
• why do aseptic agar plate not prove that all bacteria is killedby 1 antibiotic

  • only one type of bacteria
  • there's still bacteria on the plate
• safety precautions when removing blood

  • wear gloves
  • use a sterile needle
• describe two improvements to be made to an experiment regarding the Optum temperature

  • repeat the test for each temperture
  • use a small interval of temperatures
  • add a control variable if not listed in the method
• function of meristem of growing a plant

  • undiffertiaited cells
  • divide by mitosis to produce more cells
• Why are pea plants grown in a warm closed greenhouse

  • provide optical / best growth conditions
  • reduces changes of a disease from a pathogen
• controlled variables in a pH experiment

  • ph of solution
  • time - intervals
  • temperture
  • volumes of solutions
• describe an experiment to confirm the optimum pH question (amalyse in this example)

  • use different ph
  • mix starch solution with amylase
  • glucose in quickest time is optum
• how can cancer develop from cell division

  • unctronlled cell division by mitosis leads to a tumor
• how does a diverging lens(convex) correct short sightness

  • refracts light outwards
  • light rays converge on the retina
• advantagea and disadvantage of asexual reproduction

  • advantages - more produced,desired characteristics
  • disadvanatge - reduced genepool,more suspectable to environmentally change
• optum pH 6 why doesn't it work at pH 10

  • causes bond in active site to break,by changing the shape of the active site - making it denatured
• pathogen


  • organism that causes deisease
• antibitotics used to kill bacterial cells

  • kill bacteria without effecting the host
• how are messages sent from the eye to the brain

  electrical impulses along the motor neurone to an effector
• bmi waist to hip ration

  • bmi doesn't take into account muscle mass
  • alchohols increaser liver damage
  • smoking increases likely hood of cardiovascular
• describe how cause of plant diseases and distrbution can be investigated

  • use internt books to identifer the disease
  • check other plants in the field
  • examine lesions on the leaf
  • compare with known diesease
  • test the soil to identify the pathogens
  • use microscoples to analyse pathogens
• why do people who are longsighted sighted not see short distances

  • light rays converge behind the retina