Biology

• What is reaction time?

  Time taken to respond to changes
• How does light affect the growth of newly germinated seeds?

  It influences their height and direction
• What is the effect of gravity on newly germinated seeds?

  It influences the direction of growth
• What are the steps for measuring reaction time in a practical experiment?

  1. Work in pairs
  2. One person places arm on table
  3. Other holds ruler at 0 mark
  4. Drop ruler randomly, catch as soon as possible
  5. Record number caught, repeat 5 times
  6. Calculate mean reaction time
• What is the procedure for testing the effect of light intensity on seedling height?

  1. Incubate seeds in petri dishes
  2. Measure height of shoots
  3. Place dishes in full light, partial light, and darkness
  4. Record appearance and re-measure height
  5. Estimate angle of bending
• Why do seedlings in dark dishes grow longer?

  They grow rapidly to reach light
• What is phototropism?

  Growth towards a light source
• What is the effect of gravity on seedlings?

  Shoots grow up, roots grow down
• How does auxin affect root growth in response to gravity?

  It inhibits growth on the lower side
• What is the procedure for random sampling to estimate population size of a species?

  1. Create a grid using tape measures
  2. Generate random coordinates
  3. Place quadrat on coordinates and count species
  4. Repeat at multiple sites
  5. Estimate population size using formula
• What is the purpose of transect sampling in ecology?

  • To study the effect of abiotic factors on species distribution
  • Lay transect and count plants at intervals
  • Record abiotic factors at each site
• What is the effect of temperature on milk decay in the experiment?

  Higher temperatures increase decay rate
• What are the steps to prepare a microscope slide using onion tissue?

  1. Peel off epidermal layer
  2. Place on water drop on slide
  3. Add iodine solution
  4. Lower cover slip using a needle
• What is the positive result for the protein test?

  Change from blue to purple
• What indicates a positive result in the lipid test?

  White emulsion forms
• What is the positive result for the starch test?

  Turns blue-black from orange
• What is the inverse square law in relation to light intensity and photosynthesis?

  Doubling distance reduces bubbles by 4x
• What are the steps to measure the effect of light intensity on the rate of photosynthesis?

  1. Place boiling tube 10cm from LED light
  2. Fill with sodium hydrocarbonate solution and add pondweed
  3. Count bubbles produced in 1 minute
  4. Repeat at different distances
  5. Plot graph of light intensity against rate
• What are the restrictions in sustainable fisheries to maintain fish populations?

  • Net size limits to protect young fish
  • Fishing quotas to control catch amounts
• How does biotechnology help in insulin production?

  Insulin gene is transferred to bacteria
• What are the advantages of GM crops?

  • Increased food production
  • Resistance to pests and extreme weather
  • Enhanced nutritional value
• What is mycoprotein and how is it produced?

  • Produced from fungus Fusarium
  • Grown on glucose syrup in fermentors
  • Harvested and purified for food
• What are the effects of deforestation on biodiversity?

  • Destroys habitats
  • Releases CO2
  • Reduces biodiversity
• What is the role of decomposers in ecosystems?

  • Cycle materials through ecosystems
  • Return CO2 and mineral ions to soil
• What are the optimal conditions for decomposers?

  • Warm temperatures for faster activity
  • Moist environments for chemical reactions
  • Sufficient oxygen for aerobic respiration
• What is anaerobic decay and its product?

  Decay without oxygen produces methane gas
• How does temperature affect species distribution?

  • Species may migrate to warmer areas
  • Changes can be seasonal or geographic
• What is biodiversity and its importance?

  • Variety of species in an ecosystem
  • Higher biodiversity leads to ecosystem stability
• What are the effects of pollution on biodiversity?

  • Water pollution decreases oxygen levels
  • Air pollution harms plants and animals
  • Landfills destroy habitats
• What are the factors affecting food security?

  1. Increasing birth rates
  2. Changing diets
  3. New pests and pathogens
  4. Climate change
  5. Conflict affecting resources
• What are the advantages and disadvantages of intensive farming?

  Advantages:

  • Less biomass wasted
  • Controlled nutrient intake

  
  

  Disadvantages:

  • Spread of infections
  • Ethical concerns for animal welfare
• What is the carbon cycle's role in ecosystems?

  • Cycles carbon through respiration and decay
  • Returns CO2 to the atmosphere
• What is the water cycle's process?

  1. Evaporation and transpiration
  2. Condensation into clouds
  3. Precipitation to the ground
  4. Absorption by plants and animals
• How do environmental changes affect species distribution?

  • Changes in temperature and water availability
  • Pollution impacts organism growth and survival
• What effect do certain pollutants have on organisms like lichen?

  They affect their distribution
• Where do lichens grow more abundantly?

  In non-sulfur dioxide places
• What types of changes can affect species distribution?

  Seasonal, geographic, or human interaction
• How does sewage in streams affect animals?

  It drops oxygen levels
• What is biodiversity?

  Variety of different species on Earth
• How does higher biodiversity affect ecosystems?

  It makes ecosystems more stable