| Your Results | Global Average | |
|---|---|---|
| Questions | 5 | 5 |
| Correct | 0 | 3.45 |
| Score | 0% | 69% |
Which of blood component fights infection?
platelets |
|
plasma |
|
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.
The envelope of gases surrounding the planet is called the:
lithosphere |
|
atmosphere |
|
geosphere |
|
hydrosphere |
The biosphere is the global ecological system integrating all living beings and their relationships. This includes their interactions with the lithosphere (the rigid outer part of the earth, consisting of the crust and upper mantle), hydrosphere (all surface water), and atmosphere (the envelope of gases surrounding the planet).
Cirrus clouds are thin, wispy clouds composed of ice crystals. At what elevation to cirrus clouds form?
mid-altitude |
|
low-altitude |
|
high-altitude |
|
ground level |
Cirrus clouds are thin, wispy high-altitude clouds composed of ice crystals that originate from the freezing of supercooled water droplets. Cirrus clouds generally occur in fair weather and point in the direction of air movement at their elevation.
In cell biology, cytokinesis results in two separate:
cells |
|
chromatids |
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chromosomes |
|
nuclei |
During cell division, the cytokinesis phase occurs when cytoplasm and cell membranes complete their separation resulting in two separate cells.
The crust and lithosphere of the Earth is made up of which of the following?
continents |
|
sedimentary rock |
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plates |
|
metamorphic rock |
The crust and the rigid lithosphere (upper mantle) is made up approximately thirty separate plates. These plates more very slowly on the slightly more liquid mantle (asthenosphere) beneath them. This movement has resulted in continental drift which is the gradual movement of land masses across Earth's surface. Continental drift is a very slow process, occurring over hundreds of millions of years.