| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.18 |
| Score | 0% | 64% |
Which of blood component allows blood to clot?
plasma |
|
platelets |
|
white blood cells |
|
red blood cells |
Blood is created in bone marrow and is made up of cells suspended in liquid plasma. Red blood cells carry oxygen, white blood cells fight infection, and platelets are cell fragments that allow blood to clot.
Velocity is the rate at which an object changes position. What is the formula for velocity?
\(\vec{v} = { \vec{d} \over t } \) |
|
\(\vec{v} = \vec{d}t \) |
|
none of these |
|
\(\vec{v} = { t \over \vec{d} } \) |
Velocity is the rate at which an object changes position. Rate is measured in time and position is measured in displacement so the formula for velocity becomes \(\vec{v} = { \vec{d} \over t } \)
Which of the following is the formula for power?
\(P = w t\) |
|
\(P = {w \over t}\) |
|
\(P = {\vec{w} \over t}\) |
|
\(P = \vec{w}t\) |
Power is the rate at which work is performed or work per unit time: \(P = {w \over t}\) and is measured in watts (W).
What part of the food chain serves only as food for other organisms?
secondary consumers |
|
decomposers |
|
producers |
|
primary consumers |
Producers (autotrophs) serve as a food source for other organisms. Typical producers are plants that can make their own food through photosynthesis and certain bacteria that are capable of converting inorganic substances into food through chemosynthesis
Which of these is matter than cannot be separated into different types of matter by ordinary chemical methods?
molecule |
|
element |
|
atom |
|
compound |
An element is matter than cannot be separated into different types of matter by ordinary chemical methods.