Answer : Option A) He is studying oxygen, which can also be found in proteins.
Explanation : A scientist is examining the role of an element found in fats and carbohydrates of living things. Oxygen is the element which makes up to 65% of human body mass. This is also found in proteins inside the body.
Allele frequency is a measure of the relative frequency of an allele on a genetic locus in a population.
Usually it is expressed as a proportion or a percentage.
In population genetics, allele frequencies show the genetic diversity of a species population or equivalently the richness of its gene pool.
The frequencies of all the alleles of a given gene often are graphed together as an allele frequency distribution histogram.
Population genetics studies the different "forces" that might lead to changes in the distribution and frequencies of alleles - in other words, to evolution.
Besides selection, these forces include genetic drift, mutation and migration.
Answer:
Homeostasis is the process of maintaining a constant internal environment of the body with the help of certain mechanisms such as feedback loops.
Explanation:
Homeostasis refers to the maintenance of a relatively constant internal environment of the body. It includes maintaining several parameters such as acid-base balance, blood glucose level, body' temperature, etc. within the narrow range.
Homeostasis is mainly maintained with the help of negative feedback loops wherein the deviation of any parameter from the normal physiological range is counteracted and restored.
For example, the blood glucose level remains within the range of 70 and 110 milligrams of glucose per 100 milliliters of blood under normal physiological conditions. Any deviation from the range is restored with the help of pancreatic hormones insulin and glucagon.
The answer is D, Because dinosaurs appears in the Triassic period while insects appeared in the Devonian period which is about 160 million years about, which rules out A and B. Humans have been on Earth for almost 3 million years, which is nothing compared to the history of life in earth, which about 4,000 million years of life history, so D
the first answer as blood needs to be oxygenated to be passes round the body then when its deoxgenated it will return to the heart to be pumped around the body again
