Answer:
Triassic Period (252 to 201 million years ago)
All continents during the Triassic Period were part of a single land mass called Pangaea. This meant that differences between animals or plants found in different areas were minor.
The climate was relatively hot and dry, and much of the land was covered with large deserts. Unlike today, there were no polar ice caps.
It was in this environment that the reptiles known as dinosaurs first evolved. Reptiles tend to flourish in hot climates because their skin is less porous than, for example, mammal skin, so it loses less water in the heat. Reptile kidneys are also better at conserving water.
Answer:
Arteries have thick walls composed of three distinct layers (tunica) Veins have thin walls but typically have wider lumen (lumen size may vary depending on specific artery or vein) Capillaries are very small and will not be easily detected under the same magnification as arteries and veins.
Explanation:
Answer:
d. dilation of the blood vessels serving the skin and digestive viscera.
Explanation:
Cardiovascular effects of the sympathetic division include all of the following EXCEPT dilation of the blood vessels serving the skin and digestive viscera.
The main way in which <span>a decrease in the number of songbirds might be expected to affect the trees in a northern forest is that the would be overrun with more instincts due to a lack or predators. </span>
They differ in single trait
