Because through natural selection, only the fittest survive. when the fittest come together and reproduce then the species continues and evolves with only the fittest and strongest genes.
Answer:
1st is correct
Explanation:
At its simplest, a dog's digestive system is a long tunnel that runs from their mouth to the anus. Food goes in at the mouth and travels through this tube and at various stages is broken down and either absorbed into the body or excreted as waste at the anus.
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.
Answer:
Metals such as iron have low specific heat. It doesn't take much energy to raise their temperature. That's why a metal spoon heats up quickly when placed in a cup of hot coffee. Sand also has a relatively low specific heat.
Explanation:
If there were injuries to the brain stem, cerebral cortex, and/or the cerebellum then one possible injury could be a seizure or lead to a concussion. another affect could be memory loss, or worse case scenario being paralyzed
