Answer:
Oxygen is moved around the body of an echinoderm in its C. water vascular system.
Answer:
The correct answer would be D) tissue.
In biology, the level of organisation from simplest to complex level can be summarized as:
Organelles → cells → tissues → organs → organ systems → organisms → populations →communities → ecosystem → biosphere.
It is clear that tissue is organization level that exists between cells and organs.
When similar cells are assembled together to perform specific function, the assembly or this organization is said to be the tissue.
There can be different types of tissues such as muscle tissue, nerve tissue et cetera.
Similarly, tissues arrange themselves to carry out specific function in the form of organ.
For example, heart is made up of cardiac tissue.
That question, this incomplete. The full question is:
3. Three redwood trees are kept at different humidity levels inside a greenhouse for 12 weeks. One tree is left outside in normal conditions. The heights of the trees are measured once a week. What are the dependent variables, independent and the controlled variable of this experiment?
Answer:
- Independent variable: different humidity levels
- Dependent variable: the heights of the trees
- controlled variable: the types of trees
Explanation:
An independent variable is one that exerts an influence within the experiment and can be measured, acting on other elements to promote the observation of a result. As the experiment seeks to observe the influence of humidity on the height of the tree, we can say that humidity is the independent variable.
Dependent variable is that which is influenced by the independent variable to generate a result that can be observed, can also be measured. As the experiment wishes to analyze how the height of the trees was affected by the level of humidity, we can say that the height of the trees is the dependent variable.
Controlled variable is that which is present in the experiment in a constant and equal way, cannot be measured. This variable is the type of trees.
Answer:
Prophase 1
Explanation:
In prophase 1, homologous chromosomes pair up and exchange sections of DNA in a process called crossing over.
