Answer: "hazardous substance" .
_____________________________________________________
Answer: Gene that arose through gene duplication, but by acquiring mutations became nonfunctional.
Explanation:
A gene is a functional unit of heredity formed by DNA. They possess a sequence of nitrogenous bases that during translation is read by ribosomes to produce molecules called proteins. A pseudogene is a DNA sequence that resembles a gene, but which has been inactivated in the course of evolution by mutations in its sequence. Thus, it is a gene that derives from other known genes and whose functions are different, <u>may have lost their functionality or have radically changed </u>it. To this day, it is not known exactly how pseudogenes are created, however some theories are as follows:
1. A gene duplication can generate two copies of a gene when only one is needed. A mutation would then occur that deactivates one of the copies. In addition, the duplication event may not be complete, so that the copy has incomplete promoters.
2. They may be fragments of the messenger RNA transcript of a gene may be spontaneously reverse transcribed and inserted into the chromosomal DNA. They lack the promoters of normal genes, so they are not expressed normally.
3. A gene may become non-functional or inactivated if such a mutation becomes fixed in the population. This can occur by normal means such as natural selection or genetic drift.
Answer:
To control what enters and leaves the cell.
Explanation:
Answer:
cells
Explanation:
That is one of many of the cells functions.
our thyroid glands plays a main role in a human body. It secretes thyroxine and calcitonin. In which thyroxine help in growth and cellular metabolism and calcitonin helps to regulates calcium concentration in blood . If thyroid gland stops working then there is low level of calcium in our blood, which leads to mental and hormonal disorder. In this way a person's blood calcium level would be affected if his/her thyroid gland stops working.
