Answer: Option C..
controls autonomic nervous system and regulates thirst
Explanation:
Hypothalamus controls autonomic nervous system and regulates thirst because it is above the brain stem and it receive autonomic regulatory signals or information , then it then act to integrate and controls autonomic nervous system. The autonomic nervous system help to regulate different types of body functions like sexual arousal, heart rate, pupilatory rate, digestion rate , respiratory rate e.t.c.
A sex-linked trait is a trait that is carried by the X chromosomes in females but it is not expressed(the phenotype). Females are only carriers because they have two copies of the X chromosome [one of them carries the trait and the other does not]. Males who inherit one copy of the X chromosome often get the trait (because the trait is in either one copy or the other of the X chromosome) and express it while their Y chromosome would became recessive. Thus, only males express sex-linked traits such as hemophilia or color blindness
Answer:
Due to presence at early days of the planet.
Explanation:
We only find the remains of single celled organisms in the oldest fossils because the single celled organisms are the organisms that were present in the early days of this planet. These single celled microbes were present about 3.7 billion years ago while on the other hand, the oldest rocks are only a little older i. e. 3.8 billion years so these single celled organisms are considered as oldest fossils on this planet.
