A scientist observes a bee and a bird on a cool spring morning, when the temperature is 49°F. The bird immediately leaves its nest. It flies around and starts looking for insects to eat. The bee remains still, sitting in the sun on a leaf. After an hour, the temperature has risen to 57°F. The bee begins to fly around and collect pollen from flowers. Explain why the bee and the bird behave differently as the temperature changes.

not always but somethings can be reproduced in a laboratory.

the right is separation by density .

take the blood which is a good example of a heterogeneous mixture.

blood is a vital liquid in our body, which transports oxygen from the air to our lungs so we can breathe. it is also used to eject wastes, such as carbon dioxide, to bring cells and molecules of the immune system to the tissues, and to spread hormones throughout the body. it corresponds to plasma, red blood cells, white blood cells, platelets and hemoglobins combined.

in medical tests centrifugal force is used to separate the different components of the blood.

in general, the centrifugation will allow to separate and analyze the different components of the blood, to know if the rate of white blood cells in the blood of a patient, for example, is normal, and therefore to know if his system immune is integrity.

under the action of centrifugal force, the solid components in the blood are drawn to the bottom of the tube in which the blood is contained. the centrifugal force then acts as an accelerated settling. it separates plasma from red blood cells and white blood cells.