Answer:
True
Explanation:
Sound waves need a medium to travel through. That's why you cant hear sound in space. But you can see light in space and the sun heats up our planet, so yes, light doesnt need a medium to travel through.
Answer:
Answer is C.
Explanation:
A. The vessel length is pretty much constant. The body can't length or shorten blood vessels.
B. Blood viscosity is also fairly constant because the composition of blood cannot change quickly enough to change resistance as needed.
C. This is the main way resistance is controlled. The smooth muscle surrounding blood vessels can rapidly respond to hormonal or metabolic stimuli and contract/relax to adjust diameter.
D. Again, temperature is fairly constant in the body and would not be a good way to alter resistance.
Answer:
well they can be both sometimes, some can survive in very hot environments, but most can be killed by heat so it is prokaryotic
Explanation:
