Biologists recognize five levels of cell organization. The lowest and simplest is the cellular level. Organisms here are either unicellular organisms, like protozoa, or colonial organisms. Colonial organisms are composed of single-celled individuals that stay together to sustain the life of the whole colony. Next on the scale of complexity is the level occupied by tissue. A tissue is a group of similar cells that perform a similar activity. Tissues that are organized around a common function together make up an organ, the third level of complexity. The fourth level of organization is the system, formed by a group of organs that together perform a specific bodily process. The fifth and highest level is the organism level, in which body systems work together in a structure capable of independent life.
Answer:
<h2>Blood flow through a capillary is controlled by the <u>precapillary</u><u> </u><u>sphincters</u><u>.</u></h2>
Answer:
- Independent variable: Car weight (car + block with a mass of 10 grams)
- Dependent variable: Speed (the time the car takes to descend the ramp)
Explanation:
As you can see in the question above, Shawn wants to check the speed that a car takes when going down a ramp, related to the weight of this case, that is, he wants to know the influence of the weight that the car presents, in its speed in going down a ramp.
In this type of experiment, we can consider the weight that the car presents as the independent variable. This is because independent variables are those that influence a result within the experiment. They happen without the influence of another variable and are factors that impose changes in the analyzed system.
The dependent variable, however, is the car's speed down the ramp. This is because the dependent variables are those that need and are influenced by the independent variable, to achieve a result that can be measured and analyzed.