Living Systems

Which of these best explains the next level of organization in this model?

• protein

• mitochondria

• muscle cells

• atom

Scientists are developing a new class of vaccines, known as nanovaccines. A study found evidence that nanovaccines boost the immune response in mice. The scientists reported their initial findings to other scientists. What is the most logical next step in the development process?

• determine the best way to ship large quantities of the vaccine

• replicate the nanovaccine results in further studies

• collect data on the impact of vaccines in the developing world

• produce larger quantities of vaccine for use on people

In the trachea there is a layer of epithelial cells that produce mucus. The function of the mucus is to keep the trachea moist which catches debris and bacteria going to the lungs. What is this an example of?

• Cells working to maintain homeostasis.

• Cells working to produce energy for the body.

• Organs working together to maintain homeostasis.

• Organs working together to produce energy for the body.

Engineers are working to develop a new kind of artificial knee, which is used to replace damaged knees. Which of these would be considered a trade off of the artificial knee?

• The artificial knee reduces pain in people who have the knee.

• The artificial knee functions better than the knee that it replaces.

• The new artificial knee is heavier than previous artificial knees to improve its lifespan.

• The artificial knee is more resistant to wear and tear than other artificial knees.

Most starfish turn their cardiac stomach inside out to eat captured prey. The cardiac stomach digests the food outside of the body and, when complete, returns to the inside of the body. Which term applies to the cardiac stomach?

• cell

• organ

• system

• tissue

An engineer is developing a new prosthetic leg to help patients who have lost limbs to walk. The current device design will cost $10,000 to manufacture, but the cost of the item cannot exceed $8,000. How should the engineer approach this problem using the engineering design process?

• The engineer should change the cost constraint

• The engineer should move forward in the design process

• The engineer should trade off some of the safety and reliability of the design to reduce costs

• The engineer should reconsider the materials, location of manufacture, and simplify any parts of the design to reduce costs

A biologist discovers a new species of plant that grows in very humid climates. She hypothesizes that this species would not be able to regulate the size of its stoma (the pores in the leaf of the plant that allow oxygen out) when there are changes in humidity. Which experiment can she perform to best test this hypothesis?

• She waters different plants with different volumes of water and measures the diameter of stoma in each leaf.

• She trims a different amount of roots from each plant and measures the amount of glucose produced by each plant.

• She grows the plant with various levels of humidity and measures the amount of oxygen produced by each plant.

• She places leaves from the plant in solutions containing different amounts of salt and measures the time it takes the leaves to dry out.

This model shows some of the inputs and outputs for the respiratory and circulatory systems.

Which statement explains why the arrows between the atmosphere and the respiratory system are different sizes?

• The atmosphere contains more carbon dioxide than oxygen

• The respiratory system uses more carbon dioxide than oxygen

• The muscular system uses oxygen and produces carbon dioxide

• The respiratory system moves gases from the atmosphere to the muscular system

Different parts of the cell system are responsible for different functions in the maintenance of homeostasis.

What is the function of the ribosomes?

• produces cellular proteins

• produces energy for cellular functions

• stores genetic information for the cell

• controls movement of materials in and out of the cell

Cochlear implants are devices that are often implanted in patients who have trouble hearing. Choose all correct sentences that describe a risk of cochlear implants.

• Signaling from the device can cause dizziness

• Implantation of the device can cause infections

• Patients can hear other people speaking more accurately

• Patients can better determine the direction that sound comes from

• Cochlear implants have become more affordable in the last few years