Answer:
It is necessary to separate oxygenated and deoxygenated blood separate in mammals and birds to maintain their body temperature. Also, if they both are mixed, the blood will get impure and it would be difficult for the heart to supply impure blood. We also can't live with impure blood so we most probably will die.
Answer for question 1- B (eliminate all plant life)
Answer for question 3- A (Direct energy from the Sun)
(i’m not entirely sure what the answer is to question 2 and i do apologies if any of this incorrect)
Question #1: D
Question #2: B
These are the correct answers hopefully. I knew the second one, but the first one I had to look up and do a wee bit of research
1. Explain why the distribution of fossils in Figure 1 supports the hypothesis that the extinction of these species was the result of a sudden environmental change.
This hypothesis can be supported because all the fossils accumulate almost at the same age of the rock layer. That is, all the fossils died almost at the same time.
2. Describe an environmental change that could have produced this type of fossil distribution.
Good examples of sudden environmental changes are volcanoes. When a rash occurs, the whole environment suddenly changes for different reasons such as ash or lava, and all living things can die immediately or in a few years by the change in the ecosystem.
3. Explain why the distribution of fossils in Figure 2 supports the hypothesis that the extinction of these species was the result of a gradual environmental change.
This is because the fossils accumulate at different ages of the rock layer, that means, the species dying over time. The gradual descent of the fossils is observed.
4. Describe an environmental change that could produce this type of fossil distribution.
For example, if a climate change occurs - the temperature increases or decreases - it can cause the trees or plants to die and all the animals in the ecosystem also die when they have no food. But this process is sequential, so the change can take years, centuries or even millions of years.
I hope this can help you.
Answer:
EXERCISE
Explanation:
In an experiment, the independent variable is the variable that the experimenter changes or manipulates in order to bring about a measurable outcome.
In this case, an experiment is carried out to test the hypothesis that "exercise will affect the number of times a person can squeeze a clothespin in a certain amount of time". The experiment contained two groups (one group sits quietly before squeezing a clothespin as many times as possible and the other does 25 JUMPING JACKS before squeezing a clothespin as many times as possible).
The independent variable is the EXERCISE (jumping jacks) that was changed for each group in the experiment.