When a human's blood pressure increases, signals are sent from the blood vessels to the brain. Then, the brain sends a message to the heart, telling the heart rate to slow down. Is this an example of positive or negative feedback? How do you know? Explain how the situation could be the opposite (for instance, if you said that the example above is positive feedback, then explain a scenario where it could be negative feedback).

Need ! will give 20 points! what are two ways that diatoms differ from slime molds? the external coverings of diatoms are made up of (silica, chitin or peptidoglycan), while slime molds have cell walls containing (silica, peptidoglycan or chitin). diatoms are (chemoheterotrophs, photoautotrophs or chemoautotrophs) because they make food through photosynthesis, while slime molds are (heterotrophs, phototrophs or autotrophs) because they eat decaying plant matter.