Activators and repressors are transcription-control elements that are found in eukaryotic organisms. These elements function during the process of transcription, where a DNA molecule is coded onto a RNA molecule for it to be sent to ribosomes outside of the nucleus and then polypeptide chains are produced from it.
The activators and repressors control which proteins are made, which means that they can either hinder or promote certain functions in the cells of the body. Therefore, even though all of the cells have the same set of DNA, some are able to produce HCl, while others produce other substances such as insulin.
Answer:
c. Cell division increases the mass of the original cell.
Explanation:
Cell division is a process of formation of daughter cells by dividing the existing cells. As the cells grow, their surface area to volume ratio reduces which means that a larger cell has a less surface area than its volume as compared to a smaller cell. Cells need to maintain a higher surface area to perform various biological functions. Therefore, after attaining certain growth, cells divide to increase their surface area and reduce their volume. Cell division reduces the mass of the parent cell. The newly formed cells grow to increase their mass.
Receptors that provide animals with information from the external environment are located in the:
- ears
- skin
- tongue
- eyes
- nose
These receptors are known as sensory receptors as they perceive the changes that occur in the external environment and transmit the information to the nervous system.
The name of these receptors located in the respective organ is as follows :
1. Ear - auditory receptor
2. Skin - mechano (cutaneous) receptors
3. tongue - taste receptors
4. eyes - Photoreceptors
5. nose - olfactory receptors
An example of how it detects the changes in the external environment can be understood as follows :
The substances that have odor produce chemicals known as odorants which bind to the olfactory receptors located in the nose which then produces electric signals which are transmitted via the nerves to the olfactory bulb in the brain and the smell is detected.
A rising Mississippi River bottom could change the river's course in a future flood. ... "If the structures were not built and all, the river would eventually change course to that of the Atchafalaya River," said Russell Beauvais, Operations Manager for the U.S. Army Corps of Engineers.
Answer: Diploid means you have two of each type of chromosome.
Explanation:
Diploid is the term that refers to the number of each type of chromosome that an organism has. And diploid specifically means every cell in that organism has two copies of each type of chromosome.