Some diseases are caused by mutations that are inherited from the parents and are present in an individual at birth, like sickle cell disease.
The current maternal blood-screening test is also known as the triple screen test because of the testing of the three substances in the blood of a pregnant woman. These three tested components are the hCG (Human Chorionic Gonadotropin), AFP (Alpha-feto protein), and the estriol.
For the purpose of this triple screen test, the blood is drawn for the expectant mother and then this drawn blood is tested for the listed three components.
Hence, the correct answer is 'it tests for three substances in the maternal blood'.
Answer:
92 chromatids
Explanation:
During phosphate, the nuclear envelope of the cell (which is where the 92 chromatids are contained) begins to break down. The centrioles, which are the only present in animal cells, separate and each moves to an opposite end of the cell
The theory of evolution can be proved by the comparison of DNA genetic sequences of organisms.
<u>Explanation:</u>
The evolution can be proved by following
- Homologous organs - they are organs that have similar basic structure but perform different functions. example: Human, Bird.
- Analogous organs-they are organs that perform same function but have different structure or basic design. example: Bird and insect.
- Fossils- the remains of dead animals and plants.
Dead organisms get decomposed by microbes, due to the absence of oxygen and moisture some body parts does not decompose.
The soft parts of body gets decomposed hard parts take time to decompose and get covered by sea, at these deep levels the decomposition stops and the hard parts remain preserved called fossils.
