NAME:_______________________________________ Period:________ Date:__________________
Midterm Review.
1. Use the description of the experiment below to answer the questions that follow to see what
improvements should be made to fix the graph.
Methyl mercury is a toxic substance that can harm the nervous system and is measured in units
called parts per million (ppm). Some fish are contaminated with high levels of methyl mercury.
In many places, these fish are an important food source. Experiments are being conducted to
determine how many meals of contaminated fish can be safely consumed. The graph below
shows the concentration of methyl mercury in the fish and the number of meals that can be
safely consumed per month.
Questions and Answers…
a. What can you learn from the experiment that was conducted?
b. What is the dependent variable in this experiment?
c. What is the independent variable in this experiment?
2. Words that go with water…
Questions and Answers…
a. What is surface tension?
b. What is the difference between the terms “solvent”, “solute”, and “solution”? (A
drawing may help you remember)
3. What does each of the numbers on the DNA molecule represent?
1 = ____________________________
2 = ____________________________
3 = ____________________________
4 = ____________________________
4. A population of bacteria, starting with a single cell, can double in number every twenty
minutes. Create a line graph to show how much the bacteria population would grow in 80
minutes. (Hint: Use what you learned in question #1 to help you set up your graph.)
Be sure to label the graph correctly.
5. Use the description of the experiment below to answer the questions that follow:
Catalase is an enzyme found in the tissues of plants and animals, including humans. Catalase
helps prevent a toxic buildup of hydrogen peroxide in cells by breaking it down into water and
oxygen gas. Several students conduct an experiment to test the effects of pH on the activity of
catalase. Each test tube contains a solution of hydrogen peroxide and water at various pH levels.
The liver tissue is a source of catalase. The diagram below represents the results of their
experiment.
Questions and Answers…
a. What does catalase do?
b. Write an equation to show the chemical reaction performed by catalase.
c. What could a student measure in this experiment to find out if the reaction is working?
6. The sun is the primary source of energy in most ecosystems, however not every organisms can
make direct use of that energy. Describe the similarities and differences between the
processes of photosynthesis and respiration as they occur within an ecosystem.
Questions and Answers…
a. Identify the starting chemicals and final products for both processes.
Be sure to be specific and label your answer.
b. Explain how these two processes are related to each other.
7. Plants and Animal cells:
Questions and Answers…
a. Explain the difference between an animal
cell and a plant cell.
b. Why do cells (plant, animal, prokaryotic)
have ribosomes and mitochondria?
8. Cellular Transport ... A small gummy bear was placed into a water
environment. After 24 hours, the gummy bear grew to more than 3
times its original size. Using your knowledge of cellular transport,
explain what happened to the small gummy bear to make it swell.
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9. Body Systems…. Identify and explain how 3 different body systems are involved with the
process of making/excreting poop.
Body System
Involvement
10. Anaerobic Respiration … A student was investigating aerobic and anaerobic bacteria. She
learned that aerobic bacteria are found all round us while anaerobic bacteria are much less
common and are usually found deep in the soil.
Questions and Answers…
a. Explain why aerobic bacteria would be more common than anaerobic bacteria?
b. Which process is most commonly utilized by plants and animals to get their
energy? Can they perform the other process? When and why?
11. Vitamins… vitamins are organic compounds that participate in biochemical reactions, build
body structures and aid in enzyme function. Using your knowledge of the specific vitamins and
their functions, identify which vitamin each patient below is deficient in based on their
symptoms.
Vitamin
Symptoms
Patient #1 shows softening and weakening of the
bones
Patient #2 shows impaired vision, particularly in
reduced light
Patient #3 shows poor healing, tiredness, and
weakness
Patient #4 shows excessive bleeding