Question

practice 2
answer the following questions about prokaryotic and eukaryotic cells. mark the circle or circle the corresponding to your answer choice(s).

1. which of the following best describes a difference between prokaryotic and eukaryotic dna?

ⓐ prokaryotic dna is double stranded; eukaryotic dna is single stranded.
ⓑ prokaryotic dna is found in the mitochondria; eukaryotic dna is in the nucleus.
ⓒ eukaryotic dna is found in the nucleoid region; prokaryotic dna is in the nucleus.
ⓓ eukaryotic dna is found in the nuclear region; prokaryotic dna is in the nucleoid.

1. which tag of the following structures are found in both prokaryotic and eukaryotic cells?

ⓐ ribosomes
ⓑ vacuoles
ⓒ cell membranes
ⓓ endoplasmic reticulum
ⓔ golgi bodies
ⓕ nucleolus

1. which of the following best represents the average size of a prokaryotic cell?

ⓐ 1-10 μm
ⓑ 10-50 μm
ⓒ 50-100 μm
ⓓ 10-1000 μm

1. while conducting a laboratory experiment comparing prokaryotic and eukaryotic cells, a student completes the following data table for cell #1. (√ = yes, × = no)

characteristics of cell #1
cell wall: √
cell membrane: √
cytoplasm: √
dna: √
flagella: √
nucleus: ×
ribosomes: √

based on the student’s analysis, cell #1 is most likely which kind of cell?
ⓐ animal
ⓑ fungal
ⓒ plant
ⓓ bacterial

Explanation:

Problem 1 (Question about Prokaryotic and Eukaryotic DNA)

Step 1: Recall DNA structure in prokaryotes and eukaryotes

Prokaryotic DNA is typically circular (single - stranded in terms of the overall structure's topology, but the DNA molecule is double - helical), and it is found in the nucleoid region (not in a nucleus). Eukaryotic DNA is linear, double - stranded, and found in the nucleus (associated with chromosomes). Now let's analyze each option:

• Option A: Prokaryotic DNA is not single - stranded (the DNA molecule is double - helical), and eukaryotic DNA is not single - stranded. So A is incorrect.
• Option B: Prokaryotic DNA is circular (double - helical) and found in the nucleoid (not in Golgi bodies). Eukaryotic DNA is in the nucleus, not Golgi bodies. So B is incorrect.
• Option C: Prokaryotic DNA is circular (double - helical) and found in the nucleoid. Eukaryotic DNA is linear, double - helical and found in the nucleus (associated with chromosomes). This option has incorrect information about eukaryotic DNA location (says cytoplasm which is wrong). So C is incorrect.
• Option D: Prokaryotic DNA is circular (double - helical) and found in the nucleoid region. Eukaryotic DNA is linear, double - helical and found in the nucleus (in the form of chromosomes). This option correctly describes the difference.
• Option E: Eukaryotic DNA is not in the nucleoid (prokaryotic DNA is in nucleoid), and prokaryotic DNA is not in the nucleus. So E is incorrect.

Step 1: Recall cell structures

• Ribosomes: Both prokaryotic and eukaryotic cells have ribosomes. Prokaryotic ribosomes are 70S and eukaryotic are 80S (in cytoplasm, 70S in mitochondria and chloroplasts of eukaryotes).
• Vacuoles: Vacuoles are more common in eukaryotic cells (plant cells have large vacuoles, animal cells have small ones), prokaryotic cells generally don't have vacuoles.
• Mitochondria: Mitochondria are only in eukaryotic cells (except for some prokaryotic - like organelles in some organisms, but generally prokaryotes lack mitochondria).
• Cell membranes: Both prokaryotic and eukaryotic cells have cell membranes. Wait, but let's check the options again. Wait, the options are: A. ribosomes, B. vacuoles, C. vesicles, D. cell membranes, E. endoplasmic reticulum. Wait, endoplasmic reticulum is only in eukaryotic cells. Cell membranes are in both, but ribosomes are also in both. Wait, maybe I misread. Wait, the question is which structure is found in both prokaryotic and eukaryotic cells. Ribosomes are present in both (prokaryotic: 70S, eukaryotic: 80S in cytoplasm, 70S in organelles). Vacuoles: prokaryotes don't have. Vesicles: more in eukaryotes. Endoplasmic reticulum: only eukaryotes. So the correct answer is A (ribosomes).

Step 1: Recall prokaryotic cell size

Prokaryotic cells (like bacteria) typically have a size range of 1 - 10 $\mu$m. Eukaryotic cells are generally larger (10 - 100 $\mu$m or more). So the average size of a prokaryotic cell is in the range of 1 - 10 $\mu$m.

Answer:

D

Problem 2 (Structures in both prokaryotic and eukaryotic cells)