Part 4 EOC Review

MOLECULAR AND CELLULAR BIOLOGY (35% OF TEST)

SC.912.L.14.3 Cell Structure

Multiple Choice

There are some similarities between prokaryotic and eukaryotic cells. Which of the following structures is found in both prokaryotic and eukaryotic cells?

• A. lysosome

• B. mitochondrion

• C. nucleus

• D. ribosome

Explanation

Prokaryotic cells do not have membrane-bound organelles. They do contain ribosomes, which are the site of protein synthesis. 

Multiple Choice

Cells need to bring in molecules to carry out cellular processes. Often, this requires moving the molecules across the cell membrane against the concentration gradient. How do these molecules get into the cell?

• A. passive transport by diffusion

• B. active transport using ATP

• C. passive transport by osmosis

• D. phagocytosis

Explanation

Active transport requires ATP and is used when solutes need to move against a concentration gradient. 

Multiple Choice

Which type(s) of cells have genetic material that is contained in a nucleus?

• A. bacteria

• B. only animal cells

• C. protists

• D. both plant and animal cells

Explanation

Both plant and animal cells are eukaryotic. Eukaryotic cells have DNA (genetic material) contained in a membrane-bound nucleus.

Multiple Choice

Which characteristic do most plants have in common?

• A. they are unicellular

• B. they are prokaryotic

• C. they produce seeds

• D. they are autotrophic

Explanation

Almost all plants produce their own food using photosynthesis.

Multiple Choice

Which cell structure is correctly paired with its primary function?

• A. ribosome - protein synthesis

• B. mitochondrion - movement

• C. vacuole - cell division

• D. nucleus - storage of nutrients

Explanation

Ribosomes are the site of protein synthesis. Ribosomes are found both on the rough Endoplasmic reticulum and in the cytoplasm. 

Multiple Choice

The diagram below represents a cell of a green plant. Solar energy is used to produce energy-rich compounds in which structure?

• A

• B

• C

• D

EXPLANATION

Structure A is the nucleus, Structure B is the cell membrane, Structure C is a vacuole and Structure D is a chloroplast. The chloroplast is where photosynthesis takes place converting solar energy into sugars that are then converted to energy in the form of ATP.

Multiple Choice

A person with swollen gums rinses his mouth with warm salt water, and the swelling decreases. Which of the following has occurred?

• A. The swollen gums have absorbed the saltwater solution.

• B. The saltwater solution lowers the temperature of the water in the gums

• C. The salt in the solution has moved against the concentration gradient.

• D. The water in the gums has moved out due to the high concentration of salt in the solution.

EXPLANATION

The salt water solution is hypertonic to the cells of the gums. It contains a higher concentration of solute (salt) and a lower concentration of water. Water from inside the cells of the gums moves down the concentration gradient and out of the cells. 

Multiple Choice

The diagram below represents a cell.Which organelle is the site where amino acids are synthesized into proteins?

• 1

• 2

• 3

• 4

EXPLANATION

Structure 1 is a mitochondrion, Structure 2 is a ribosome, Structure 3 is the cell membrane and Structure 4 is the nucleus. 

Multiple Choice

Which of these best completes this concept map?

• A. an animal cell

• B. a prokaryotic cell

• C. a virus

• D. a plant cell

EXPLANATION

Plant cells have a rigid coat of cellulose, which animal cells do not have. 

Multiple Choice

Which of these best completes this concept map?

• A. an animal cell

• B. a prokaryotic cell

• C. a virus

• D. a plant cell

EXPLANATION

Plant cells have a rigid coat of cellulose, which animal cells do not have

Multiple Choice

The cell membrane of the red blood cell will allow water, oxygen, and carbon dioxide to pass through. Because other substances are blocked from entering, this membrane is called

• A. perforated

• B. semi-permeable

• C. non-conductive

• D. permeable

EXPLANATION

A semi-permeable membrane allows some, but not all, molecules and ions to pass through

SC.912.L.18.9 Photosynthesis and Cellular Respiration

Multiple Choice

The diagram below shows the relationship between photosynthesis and cellular respiration and the organelles in which they occur.Which statement describes how photosynthesis and cellular respiration are interrelated?

• A. Oxygen is produced during cellular respiration and stored during photosynthesis.

• B. Carbon dioxide and water released by cellular respiration are used in photosynthesis.

• C. Photosynthesis releases the energy that is stored during the process of cellular respiration.

• D. Glucose is used during cellular respiration to produce food that is broken down during photosynthesis.

Explanation

The products of cellular respiration (CO2 and H2O) are the reactants of photosynthesis. The overall equations for photosynthesis and cellular respiration are the reverse of each other. 

Multiple Choice

Which gas is removed from the atmosphere during photosynthesis?

• A. hydrogen

• B. oxygen

• C. nitrogen

• D. carbon dioxide

Explanation

The reactants of photosynthesis are carbon dioxide and water. 

Multiple Choice

A weightlifter is using heavy weights in short bursts for a competition. Because his muscle cells are not able to take in enough oxygen to make very much ATP the weightlifter begins to get fatigue in his muscles. Which of the following processes is most likely going on in the muscles of the weightlifter as he competes in his event?

• A. As the cells run out of oxygen they switch to anaerobic respiration, which allows the cell to make small amounts of ATP in the absence of oxygen.

• B. As the cells run out of oxygen, they die off gradually and the weightlifter's muscles have fewer contracting muscle cells.

• C. The cells will never run out of oxygen if the weightlifter is breathing.

• D. As the cells run out of oxygen, they will continue to make the same amount of ATP, since oxygen is not required to make ATP.

Explanation

Anaerobic respiration is used by cells in the absence of ATP. This process converts sugars to alcohol and only creates a small amount of ATP compared to aerobic respiration. 

Multiple Choice

What function does ATP carry out in living things?

• A. aids in protein folding and coiling

• B. used to capture and transfer energy

• C. identifies DNA start sequences for transcription

• D. helps maintain the fluidity of cell membranes

Explanation

ATP is the “energy currency” of cells. Energy is stored in the bonds of this molecule and is released to do work in the cell when the bonds are broken. ATP is created during cellular respiration. 

Multiple Choice

How are cellular respiration and photosynthesis related, in terms of energy?

• A. The energy captured in photosynthesis is used to power cellular respiration.

• B. The energy transformed in cellular respiration is used to power photosynthesis.

• C. Photosynthesis and respiration perform the same task in terms of energy transformation.

• D. Energy is not involved in either photosynthesis or cellular respiration.

Explanation

Energy from the sun is used captured during photosynthesis and stored in the bonds of glucose molecules. During cellular respiration, this energy transferred to ATP molecules to be used to do work in the cell. 

Multiple Choice

Two different species of bacteria are examined. Scientists find that species X always produces CO2 and H2O during cellular respiration. Species Y always produces ethyl alcohol and CO2. Which conclusion can be made from these observations?

• A. Only species Y is aerobic.

• B. Only species Y is anaerobic.

• C. Both species X and Y are aerobic

• D. Both species X and Y are anaerobic.

Explanation

Anaerobic cellular respiration converts sugars to ethyl alcohol and carbon dioxide in the absence of oxygen.

Multiple Choice

In which way are photosynthesis and cellular respiration different?

• A. Cellular respiration stores ATP, while photosynthesis releases ATP.

• B. Cellular respiration produces oxygen, while photosynthesis uses oxygen.

• C. Photosynthesis releases energy, while cellular respiration stores energy.

• D. Photosynthesis used carbon dioxide, while cellular respiration produces carbon dioxide.

Explanation

The reactants of photosynthesis are the products of cellular respiration. 

Multiple Choice

A diagram representing the relationship between photosynthesis and cellular respiration is shown below.The numbered boxes in the diagram represent which of the following?

• A. 1 - water; 2 - nitrogen

• B. 1 - nitrogen; 2 - oxygen

• C. 1 - oxygen; 2 - carbon dioxide

• D. 1 - carbon dioxide; 2 - water

Explanation

Photosynthesis by plants produces oxygen, which is then used by animals as a reactant in cellular respiration. The product of cellular respiration is carbon dioxide, which is used by plants in photosynthesis. And the cycle continues.

Multiple Choice

Cell theory was first proposed in 1838. Evidence obtained through additional scientific investigations resulted in the current cell theory. Which statement describes a component of the original cell theory that was removed because of the new scientific knowledge?

• A. All living things are made of cells.

• B. All cells come from other preexisting cells.

• C. Cells form through spontaneous generation.

• D. Cells are the basic structural and functional units of life.

Explanation

It was once believed that cells could form on their own. We now know that cells must form from preexisting cells

Multiple Choice

Which invention from the 17th century allowed for the development of modern cell theory?

• A. X-rays

• B. computers

• C. the light microscope

• D. the scanning electron microscope

Explanation

The light microscope allowed scientists to view actual cells for the first time. 

SC.912.L.18.12 Properties of Water

Multiple Choice

Water is essential for life. Its special properties make water the single most important molecule in plant life. Which of the following properties of water enables it to move from the roots to the leaves of plants?

• A. Water expands as it freezes.

• B. Water is an excellent solvent.

• C. Water exhibits cohesive behavior.

• D. Water is able to moderate temperature.

Explanation

Cohesion means that water molecules are attracted to each other and attracted to other substances, such as the walls of the xylem of plants. The water molecules behave this way because they are polar. 

Multiple Choice

Large bodies of water, such as lakes and oceans, do not quickly fluctuate in temperature. What is the reason for this phenomenon?

• A. Water is an acid.

• B. Water is a versatile solvent.

• C. Water has a high heat capacity.

• D. Water acts as a buffer.

Explanation

Water can absorb a large amount of energy without a large rise in temperature. This is called heat capacity. As the sun shines on bodies of water, they absorb great amounts of its energy without a large fluctuation in temperature. 

Multiple Choice

Why does ice stay at the top of oceans instead of sinking to the bottom?

• A. Ice is colder than liquid water.

• B. Ice is less dense than liquid water.

• C. Ice is more dense than liquid water.

• D. Ice is warmer than liquid water.

Explanation

As water freezes, its molecules spread apart into a specific arrangement that makes frozen water less dense than liquid water. 

Multiple Choice

Water is often called the "universal solvent" because many substances can be dissolved in water. What property of water allows it to be such a versatile solvent?

• A. purity

• B. polarity and cohesion

• C. high heat capacity

• D. expansion upon freezing

Explanation

Water molecules are polar. This means that they have slight positive and negatively charged ends. Water molecules are attracted to a wide variety of molecules because of those charges and thus, acts as a solvent for a variety of compounds.