Mammary glands are a defining feature of which class of animals? MCQ with Answer and Explanation

Explanation:
The midbrain (mesencephalon) is the uppermost part of the brainstem. Its dorsal surface features four rounded elevations called the corpora quadrigemina (meaning 'four bodies'). These consist of two upper, larger swellings called the superior colliculi, which are reflex centers for visual movements (like tracking moving objects), and two lower, smaller swellings called the inferior colliculi, which are part of the auditory pathway and relay sound information to the thalamus.

Explanation:
In aerobic respiration, oxygen accepts electrons at the end of the ETC, forming water. Without it, the chain would halt. This directly explains why oxygen is required.

Explanation:
The heart is a muscular pump that circulates blood through the cardiovascular system, delivering oxygen and nutrients to tissues and removing waste. The lungs are the primary organs of the respiratory system, where gas exchange occurs: oxygen diffuses from the alveoli into the blood, and carbon dioxide diffuses from the blood into the alveoli to be exhaled. The kidneys are the primary excretory organs, filtering blood to remove metabolic waste, excess water, and ions, producing urine. All statements are correct.