Question

data analysis: organelle numbers

although illustrators draw cells with just a few of each type of organelle, there can be hundreds or thousands of each organelle within just one cell. the number of each organelle can vary between species and between tissue types.

discussion questions:

number of each type of organelle

	rough er	lysosome	mitochondria	smooth er
cell 2	72	21	83	6
cell 3	0	0	0	0
cell 4	10	6	9	41

1. a biologist was studying a few different types of cells from a mouse. unfortunately, he got distracted and forgot which cells were which. based on the data that he already recorded above, help him identify his cell samples.

a. muscle cells need high amounts of protein and energy. which cell is likely a muscle cell?
b. ovarian cells produce high amounts of hormones, which are a type of lipid. which cell is likely from an ovary?
c. white blood cells are responsible for ridding the body of invading bacteria and viruses. which cell is likely a white blood cell?
d. which cell is prokaryotic?

1. a researcher analyzes the molecular composition of two different organelles and notices that the first one has far more amino acids in it than the second one. which organelle would likely be the smooth er and which would be the rough er? why?

1. smooth er is responsible for synthesizing lipids and detoxifying the blood. when drugs, alcohol, or medicines are consumed regularly, the amount of smooth er increases. your friend has a seizure disorder and is prescribed a medication called phenobarbital to treat the symptoms. explain why her doctor has had to increase the strength of the prescription over the past few years of treating her.

Explanation:

Identify cells based on organelle counts

• 1a (Muscle cell): Needs high protein (Rough ER) and energy (Mitochondria). Cell 2 has the highest Rough ER (72) and Mitochondria (83).
• 1b (Ovarian cell): Produces lipid hormones, requiring high Smooth ER. Cell 4 has the highest Smooth ER (41).
• 1c (White blood cell): Destroys pathogens, requiring high Lysosomes. Cell 1 has the highest Lysosome count (60).
• 1d (Prokaryotic cell): Lacks membrane-bound organelles. Cell 3 has 0 for all listed organelles.

Compare amino acid composition of ER types

• Rough ER is studded with ribosomes, which are composed of proteins (made of amino acids) and RNA.
• Smooth ER lacks ribosomes.
• Therefore, the organelle with far more amino acids is the rough ER.

Explain drug tolerance and smooth ER proliferation

• Regular consumption of phenobarbital stimulates the proliferation of smooth ER in liver cells to increase detoxification capacity.
• This accelerated rate of drug metabolism decreases the medication's efficacy over time.
• Consequently, the doctor must increase the dosage to achieve the same therapeutic effect.

Answer:

Question 1

a. Cell 2
b. Cell 4
c. Cell 1
d. Cell 3

Question 2

The first organelle (with more amino acids) is the rough ER, and the second is the smooth ER. This is because the rough ER is covered with ribosomes, which are highly abundant in proteins made of amino acids, whereas the smooth ER lacks ribosomes.

Question 3

Regular use of phenobarbital causes the smooth ER in liver cells to proliferate to detoxify the drug more rapidly. Because the body metabolizes the medication faster, a higher dose (increased strength) is required over time to maintain the same therapeutic level in the bloodstream.