An endoskeleton (internal skeleton) is a charateristic of vertebrate animals, including humans.

The stratosphere is just above the troposphere and is stratified in temperature with warmer layers higher and cooler layers closer to Earth. This increase in temperature is a result of absorption of the Sun's radiation by the ozone layer.

The respiratory system manages respiration which is the process by which blood cells absorb oxygen and eliminate carbon dioxide.

The cerebrum is the major part of the brain and is responsible for the main senses (thinking, hearing, seeing).

Velocity and displacement are vector quantities which means each is fully described by both a magnitude and a direction.  In contrast, scalar quantities are quantities that are fully described by a magnitude only.  A variable indicating a vector quantity will often be shown with an arrow symbol:  \(\vec{v}\)