Answer
At week 5-6 of gestation, the baby’s heart starts beating.
Explanation
Fertilization occurs in week 3 followed by implantation in week 4.In week 5 the levels of hormones increases with formation of the baby’s heart and circulation system. In week 6, the neutral tube closes followed by development of structures necessary to form eyes and ears. The head of the baby develops at week 7 followed by nose in week 8 and toes in week 9.
<span>The Archaea constitute a domain and kingdom of single-celled microorganisms.</span>
The answer is A) prepares organisms for future changes in the environment
Answer:Dark matter is invisible and does not emit electromagnetic radiation. Dark matter is part of a theory that hypothesis the existence of a counterpart to the particles we know in physics, in order to balance the universe that otherwise would be largely unbalanced right now. However, the theory right now is not yet proven.
Explanation:done
Answer:
There are a bunch of things.
Explanation:
Smoking and Tobacco.
Diet and Physical Activity.
Sun and Other Types of Radiation.
Viruses and Other Infections.
Hope this helps!
