Abiology student is investigating tropisms in plants. the student observes the response of the roots of radish seedlings to a light source placed to the right of the roots. all of the roots grow away from the light source. which of the following tropisms is the student most likely investigating?

gravitropism

thigmotropism

hydrotropism

phototropism

phototropism

Explanation:

The student was investigating phototropism.

The student wanted to know the response of the roots to light, that is why he exposed them to light.

Roots naturally exhibit two types of tropisms.

The first is gravitropism whereby they tend to grow downwards.

The second is hydrotropism whereby they grow towards the direction of water.

In the above experiment, no water was provided, the roots grew away from the light source but not specifically downwards.

the answer is sex-linked recessive.

measuring light intensity

light meters can be used to measure light intensity. the meter is held at the soil surface and pointed in the direction of the maximum light intensity, and then the meter is read.

errors can be made when measuring light intensity by accidentally shading the light meter. the reliability of the results can be checked by taking many samples.