| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.22 |
| Score | 0% | 64% |
What prevents blood pumped out of the ventricles from flowing back into the heart?
capillaries |
|
valves |
|
platelets |
|
atria |
The heart is the organ that drives the circulatory system. In humans, it consists of four chambers with two that collect blood called atria and two that pump blood called ventricles. The heart's valves prevent blood pumped out of the ventricles from flowing back into the heart.
"An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force." This describes which of Newton's laws of motion?
second |
|
first |
|
third |
|
fourth |
Also known as the law of inertia, Newton's first law of motion states that An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
The __________ nervous system regulates involuntary activity in the heart, stomach, and intestines.
somatic |
|
central |
|
peripheral |
|
autonomic |
Part of the peripheral nervous system, the autonomic nervous system regulates involuntary activity in the heart, stomach, and intestines.
Which of the following is the formula for work?
\(W = {{F}\over{d}}\) |
|
\(W = \vec{F}\vec{d}\) |
|
\(W = {\vec{F} \over \vec{d} }\) |
|
\(W = {F}{d}\) |
Work is performed on an object when an applied force causes displacement along the same vector. Measured in joules (J) or newton-meter (Nm), work is calculated by multiplying force times displacement: \(W = \vec{F}\vec{d}\)
Convert 0C° to F°.
0 |
|
-32 |
|
32 |
|
16 |
To convert from C° to F° use:
\(F° = {9 \over 5}C° + 32\)
\(F° = {9 \over 5}(0) + 32\)
\(F° = 0 + 32 = 32\)