*Blood flow is regulated in all three types of blood vessels through constriction and dilation.
*Contraction of blood vessels slows blood flow, while relaxation of blood vessels, or dilation, allows free flow of blood.
*Muscle fibers control the constriction and dilation of vessels. In the capillaries, rings of muscle called capillary sphincters control blood flow.
*The directional flow of blood in the veins is controlled with valves , which prevent backward blood flow when closed, and allow blood to flow only toward the heart when open.
Vasoconstriction and vasodilatation allow blood vessels (arteries and veins) to control blood flow and thus control the blood pressure. This is possible because of the smooth muscle cells that surround the vessels. The contraction and dilatation of those muscles is controlled by chemical signals (e.g. norepinephrine constricts the vessels, while NO dilates them).
Secondary consumers receive less energy from the food chain than primary consumers.
Primary consumers are herbivores, meaning they eat the plants that have 100% energy.
Secondary consumers are either omnivores or carnivores. This means that they eat both animals and plants. In the situation that a secondary consumer is a carnivore, the secondary consumer is receiving less energy from the primary consumer.
Hope this helps!
The answer is; true
These microbes are usually adapted to their environment and this is why they are found in virtually all ecosystems. You will find bacteria even at the bottom of deep ocean beds deep and in geothermal vents, hypersaline water and very cold regions (such as polar regions). Fungi which vary widely in size from microscopically small to the largest organisms such as mushrooms are also found in virtually all environments on earth. They are nonetheless different species of these groups adapted to their environments.
Instead of burning coal to power our country we could use solar panels. As long as we have the sun we will have "free" energy.
Instead of continuing to mine for metals, we could recycle metals and then less greenhouse gases would be released into Earth's atmosphere.
Answer;
C.Identify each bird species by using a dichotomous key.
Explanation;
-A dichotomous key is a tool that is used to determine the identity of items in an ecosystem or a particular habitat, such as trees, birds, wildflowers, mammals, reptiles, rocks, and fish. To study the interactions of different birds , identifying each birds species using a dichotomous key would be an important and appropriate step.
