Prelim Bio Mod 3 Part 1 Selection Pressures

The effect of an environmental factor that differentially influences survival and reproduciton of members of a population is referred to as a:

• Selecting Pressure

• Selecting Agent

• Selective Advantage

• Selective Disadvantage

A specific environmental factor that creates/is repsonsible for a selection pressure is referred to as a:

• Selecting Pressure

• Selecting Agent

• Selective Advantage

• Selective Disadvantage

Choose the BIOTIC Selecting agents from the following:

• cheetah

• myxoma virus

• wave action

• tidal exposure

An increased ability to survive or reproduce under a given selection pressure is referred to as a:

• Selection Pressure

• Selective Agent

• Selective Advantage

• Selective Disadvantage

Predation by cheetahs creates strong selection pressure for wildebeest to be fast runners. The Selecting pressure in this example is the:

• Cheetah

• Predation by the cheetah

• Long legged wildebeest

• Running fast

Intense wave action creates a selection pressure for barnacles to be cemented to the rockface. In this example it would be a selective disadvantage for the barnacles to:

• be filter feeders

• have the ability to cement themselves to the rockface

• not have the ability to cement themselves to the rockface

Cane toads can act as a selecting agent on red bellied black snakes. The larger cane toads are more poisonous and therefore lethal to the snakes who eat them. The smaller cane toads are less poisonous and not as lethal. Overtime this will result in a change in snake population. Which snakes have the selective advantage in this example?

• Snakes with small head size

• Snakes with large head size

Natural Selection is:

• a process which explains how evolution occurs.

• is sometimes referred to as 'Survival of the fittest'

• evolution

• Both A and B

In reference to Natural Selection which of the following is not true:

• Organisms with favourable traits or a selective advantage will survive.

• Organisms with unfavourable traits or a selective disadvantage will not survive.

• Organisms with favourable traits or a selective advantage will not survive.

• When organisms with favourable traits reproduce they pass on the genes for that trait.

A favourable trait referred to in Natural Selection is a:

• Selecting agent

• Selecting pressure

• Selective advantage

• Selective disadvantage