biodiversity within a community exam questions

Question 1

The ecologists also determined the index of diversity of lizards in an oil palm
plantation next to the woodland area. They found fewer species of plant in the
oil palm plantation. Lizards feed on plants and insects.
Explain why fewer species of plant would lead to fewer species of lizard in the
oil palm plantation. (3)

Answer 1

-less variety of food sources
-fewer habitats/niches
-so lower diversity of insects.

Question 2

Ecologists investigated the size of an insect population on a small island. They used a
mark-release-recapture method. To mark the insects they used a fluorescent powder. This
powder glows bright red when exposed to ultraviolet (UV) light.
(a) The ecologists captured insects from a number of sites on the island. Suggest how
they decided where to take their samples. (2)

Answer 2

-draw grid of area
-select coordinates at random.

Question 3

give two assumptions made when using the mark-release-recapture method. (2)

Answer 3

-no immigration
-no losses due to predation

Question 4

) Suggest the advantage of using the fluorescent powder in this experiment (2)

Answer 4

-only glows in UV light- does not make insects more visible
-does not increase chance of predation.

Question 5

Suggest an explanation for the relationship between the concentration of
herbicide and the mean crop yield. (2)

Answer 5

-at high concentrations of herbicide- toxic to plants
-kills weeds so more plants survive.