B7

Question 1

Explain why plants have evolved to have complex methods of dispersing their seed

Answer 1

• to reduce competition so that offspring will grow in a different area
• so they are not competing for the same resources (e.g: light or space)

Question 2

What is abiotic and biotic?

Answer 2

• non - living (eg: light intensity, temperature, moisture, wind intensity+direction)
• living (avaliablity to food, new predators, new pathogens, comepetition/ one species outcompeting)

Question 3

Discuss a range of biotic and abiotic factors which could affect the disturtion of dandelion in a this field

Answer 3

• light intensity = affected by the shed causing shade so less photosynthesis meaning making less glucose for respiration causing less growth
• competition = around the trees/grass there may be fewer dandelion as there is more competition from the tree/grass for resources such as light, spcae , mineral ions, water
• there are no growth on the path as they would be trampled on by humans or machinery

Question 4

Describe with an example, the three different categories of adaptation

Answer 4

• structural = changes in the physical features (e.g: long tail for balance)
• behaviourial = changes in how the animal + plant act (e.g: birds migrating)
• functional = changes in the way life process (e.g: camels produce more concentrated urine

Question 5

What is the equation for estimated population size?

Answer 5

total area of the field / area of quadrat x mean number of daises counted

Question 6

What do you need to talk about in the carbon cycle?

Answer 6

• decomposition (worms bacteria)
• respiration (by the decomposers, animals and plants)
• “locked up” : in sedimentaary rocks or fossil fuels ( co2 is removed from the atmosphere)
• photosynthesis (co2 is removed from the atmosphere)
• feeding “carbon compound are passed along the food chain”

Question 7

Liist 3 examples each of adaptation for arctic and desert animal

Answer 7

Arctic animals:

• thick white fur = insulates their bodies and keeps them
  warm
• small ears = reduce the amount of heat lost to the environment
• hibernate in winter = conserve energy when there isn’t much food around

Desert animals:

• thin layer of fat = give less insulation
• largers ears = help them lost heat
• large feet = reduce pressure and avoid sinking in sand