The statements that correctly describe gestation are: the normal period of gestation is about 40 weeks; the stages of this process include: zygote, blastocyst, embryo, and fetus; and changes to the form of the embryo come from differentiation and growth.
The gestation period in humans lasts about 40 weeks and comprises different stages and processes from conception until birth. The main stages of this process include:
- Zygote: Fertilized ovum.
- Blastocyst: Cluster of cells that is the result of the zygote going through cell division.
- Embryo: Unborn human that is still developing, usually before the 8th week of gestation.
- Fetus: Unborn human in development after the 8th week of gestation.
Moreover, this process implies differentiation as cells specialize for specific functions, for example, muscle cells or nerve cells, and growth as the number of cells increases and therefore the embryo or fetus increases in size.
Learn more about embryo in: brainly.com/question/1673695
Answer:
Thyrocalcitonin or TCT
Explanation:
Thyrocalcitonin or TCT is a non-iodinated calcium lowering hormone. It is originating from the parafollicular cells or C cells (C for calcium).
The thyroid gland consists of follicles of cuboidal epithelial cells. These cuboidal cells have a nucleus at the base. These are principal cells responsible for the synthesis of thyroid hormones.
In between these follicular cells, other high cuboidal cells are present, known as parafollicular cells / C cells. These cells synthesise the hormone TCT. When there is high levels of calcium ions in the serum, TCT will release. This lowers the high level of calcium ions in the blood and plasma to normal level. This is done due to the deposition of calcium in the bone.
An animal that eats only plants is called a herbivore because it comes from herbs
The correct answer is letter B, burning wood. This is not a renewable resource of energy as its by-product involves the release of greenhouse gases that can still be harmful to the atmosphere or to the environment in general. All the other choices are good sources of renewable power because they harness the power of naturally occurring materials found in their space.
D is the correct answer. (Panting in a dogs increases the amount of cool air in nasal passages and lowers body temp).
