Cell structures that are in plant cells are cell walls, central vacuole, and chloroplast.
I just took the test, the answer is weathering.
Because hormones secreted by endocrine glands regulate the activity of body cells ..the release of body hormones into the blood is controlled by a stimulus either causes an increase or a decrease in the amount of hormone secreted .
Answer:
Una variable de control (o constante científica) en la experimentación científica es un elemento experimental que es constante y sin cambios durante el curso de la investigación. ... Las variables de control en sí mismas no son de interés primario para el experimentador.
Explanation:
<span> For a start, when you have a question that needs answering in science, you formulate a null hypothesis. That is a negative statement which you then set out to prove or disprove. This is just a convention. So if your initial question is for example, "Does sugar dissolve in water?"
Your null hypothesis will be "Sugar does not dissolve in water."
You then set up your experiment and get some data.
Now if your data doesn't support your null hypothesis then you reject it and make the statement ,"Sugar does dissolve in water." As you can see from this simple example, a non-result is still a result so the idea of formulating new tests as mentioned by another answerer isn't necessary and in some ways is the incorrect thing to do. In science, hypotheses are often not supported by data and i would argue that this is the case a lot of the time. A non-result is still a result and you will have plenty to write about whichever way it goes. </span>
