Answer:
The circulatory system of the human body consists of three types of vessels which carry blood. These blood vessels have been distinguished on the basis of structure and function and called arteries, veins and capillaries.
<u>Structure
</u>
1. Lumen diameter: Arteries have a large diameter as compared to veins and capillaries and capillaries has the smallest diameter in all of these.
2. Wall thickness: Arteries have the thickest wall than veins and capillaries have the thinnest wall.
3. Wall layer: arteries and veins made of three layers of muscle whereas veins made of one layer of cells.
<u>Function
</u>
1. Arteries: brings oxygenated blood (oxygen-rich) from the heart to the body parts in pulses
2. Veins: carry deoxygenated blood from the body to the heart
3. Capillaries: carry both oxygenated and deoxygenated blood away from the body.
Examples of index fossils include: Ammonites were common during the Mesozoic Era (245 to 65 mya), They were not found after the Cretaceous period, as they went extinct during the K-T extinction (65 mya).
Answer:
RNA polymerase (green) synthesizes RNA by following a strand of DNA. RNA polymerase is an enzyme that is responsible for copying a DNA sequence into an RNA sequence, duyring the process of transcription.
Explanation:
Answer:
Explanation:
Animal genomes can have huge numbers of genes; in order to understand the control and evolution of the basic body plan it is vital to understand the details of all 10-20,000 genes in the genome and how they act independently of one another.
The CNS are lined by ependymal cells. Ependymal cells are epithelial cells that monitor the composition of cerebrospinal fluid (CSF)
