Plant cells have cell walls and animal cells do not because the plant cell needs it for its activities.
Answer:
Hybrids are the offspring of two species. A mule is the hybrid offspring of a female horse and male donkey. Because mules are sterile, they are not classified as a distinct species. The biological species concept connects the idea of a species to the process of evolution.
Answer:
Primary Succession
Explanation:
Primary Succession is a barren area exposed by a retreating glacier
The answer would be letter C
Answer:
The blood pressure is increased to pump more blood to distribute more oxygen to the muscles
Explanation:
When we do activities that demand heavy exercise like running, our body needs more oxygen to carry out property the exercise. Oxygen is transported to muscles by the circulatory system (principally blood), our heart starts to pump faster the blood ( increase the blood pressure) to distribute the oxygen between muscles, consequently, we start to breathe faster to increase the oxygen intake.
