In class, your professor shows you the skulls of three mammals. In one, the eye would be fully enclosed by bone. In the second,
there is a bony circle around where the eye goes, but it is open in the back. In the third, the place where the eye would be is not encircled by bone at all. This suggests to you that
The first one is an anthropoid primate; the fully enclosed orbit is probably beneficial in an organism that relies heavily on vision.
Anthropoids are a group of primates currently represented by New and Old World monkeys, great apes and humans. They differ from other groups of primates such as strepsirrhines (lemurs) by several dental and cranial features (postorbital closure, shorter muzzles, increased vision due to more frontal eye sockets, fused frontal bone). The common ancestor of living anthropoids - including monkeys, apes and humans - arose in Africa and that the group had already branched into many species at that time.
The guidelines for making good and accurate observations are:
1. Standardise the experimental setup: Know the precision and the accuracy of the instrument used to make observations. Example, thermometer with a least count of 1°C cannot measure in fractional values.
2.Take careful measurements: Holding the instrument properly without causing any disturbance is the key.
The main input of cellular respiration is oxygen. The oxygen goes into the blood which then goes to the tissues. The main output is Carbon Dioxide. The carbon dioxide goes from the tissues, to the blood, and then to the lungs.