Answer:
a. heart development.
Explanation:
As the third week of fetal development starts, the process of formation of blood vessels begins. Also, the splanchnic mesoderm in the head end of the embryo forms heart on days 18 and 19. Since it develops heart, this part of the mesodermal cells is called the cardiogenic area. The underlying endoderm sends the induction signals to these mesodermal cells to form a pair of endocardial tubes that gradually develop into a single primitive heart tube.
This primitive heart begins to beat by the end of the third week of development. Therefore, any drug that affects fetal development during the first 20 days of the pregnancy might affect the development of the heart.
What do you mean by "What is a shooting star, a comet or a meteor burning in our Earth’s Atmosphere?"
edit: ohhhhh you are asking what a shooting star is...
its particles of comets or astoroids/metor enter the atmosphere at very high speeds and burn up
Answer:
Answer:
<h3>C. The organism's shape and size</h3>
This is a physical form of a fossil and can be seen by the eyes even in a glimps you can learn or differentiate it. Once you saw it you can exactly learn the fossil. The others needed a great nvestigation and research in order for them to be found.
Answer:
Mechanical to Thermal
Explanation:
When you exercise, you are using mechanical energy to get your body moving. When you start sweating, your body is heating up, so it is thermal energy.
They are equals in their own way and form