Explanation

Epidemiology, the study of epidemics, is sometimes defined as the medical aspect of ecology, for it is the study of diseases in animal populations. 

Explanation

Bioenergetics is the branch of biochemistry that focuses on how cells transform energy, often by producing, storing or consuming adenosine triphosphate (ATP).

Bioenergetic processes, such as cellular respiration or photosynthesis, are essential to most aspects of cellular metabolism, therefore to life itself.

Explanation

Thomas Harriot, of course, was very likely the first person to see sunspots through a telescope in December 1610.

Sun is a star

Explanation

 The Sun is a huge, glowing sphere of hot gas.

Most of this gas is hydrogen (about 70%) and helium (about 28%).

Carbon, nitrogen and oxygen make up 1.5% and the other 0.5% is made up of small amounts of many other elements such as neon, iron, silicon, magnesium and sulfur.

Explanation

Explanation

 Sound energy is a form of energy that can be heard by living beings.

Only those waves that have a frequency of 16 Hz to 20 kHz are audible to humans.

Explanation

The earth experiences day and night is the correct answer.

Explanation

Explanation

The mantle–core boundary is the Gutenberg discontinuity at a depth of about 2,800 kilometres.

The outer core is thought to be liquid because shear waves do not pass through it.

Explanation