Cell Structure Comparison Quiz

Study Notes

Cell Structure Comparison

Prokaryotic Cells:
- Size: Typically 0.1 to 5.0 micrometers.
- Nucleus: No true nucleus; genetic material is in a nucleoid region.
- Organelles: Lack membrane-bound organelles.
- Cell Wall: Usually present (e.g., peptidoglycan in bacteria).
- Membrane: Plasma membrane present, often with infoldings.
- Ribosomes: Smaller (70S) ribosomes.
- DNA: Circular and plasmid forms; often one chromosome.
- Cytoskeleton: Minimal structure.
Eukaryotic Cells:
- Size: Generally larger, 10 to 100 micrometers.
- Nucleus: True nucleus with a nuclear membrane.
- Organelles: Contain various membrane-bound organelles (e.g., mitochondria, endoplasmic reticulum).
- Cell Wall: Present in plants (cellulose) and fungi (chitin); absent in animal cells.
- Membrane: Plasma membrane with sterols (e.g., cholesterol).
- Ribosomes: Larger (80S) ribosomes.
- DNA: Linear chromosomes; multiple chromosomes organized in pairs.
- Cytoskeleton: Well-developed structure for support and transport.

Reproduction Methods

Prokaryotic Reproduction:
- Asexual reproduction primarily through binary fission.
  - Process:
    1. Cell elongation.
    2. DNA replication.
    3. Division into two daughter cells.
- Genetic exchange can occur via:
  - Conjugation (direct transfer of DNA).
  - Transformation (uptake of free DNA).
  - Transduction (transfer of DNA via viruses).
Eukaryotic Reproduction:
- Asexual reproduction via mitosis.
  - Process:
    1. Chromosome duplication.
    2. Division of the nucleus followed by cytokinesis.
- Sexual reproduction involving meiosis.
  - Process:
    1. Meiosis produces gametes (haploid cells).
    2. Fertilization restores diploid state.
- Some eukaryotes can reproduce asexually through budding, fragmentation, or spores.

Cell Structure Comparison

Prokaryotic cells range in size from 0.1 to 5.0 micrometers, while eukaryotic cells are generally larger, measuring 10 to 100 micrometers.
Prokaryotic cells lack a true nucleus; their genetic material is located in a nucleoid region, whereas eukaryotic cells possess a defined nucleus enclosed by a nuclear membrane.
Membrane-bound organelles are absent in prokaryotic cells, but eukaryotic cells contain various organelles like mitochondria and endoplasmic reticulum.
Prokaryotic cell walls are typically made of peptidoglycan, while eukaryotic plants have cell walls made of cellulose, fungi have chitin, and animal cells do not have cell walls.
Prokaryotic plasma membranes may have infoldings, while eukaryotic plasma membranes contain sterols like cholesterol for stability.
Ribosomes in prokaryotic cells are smaller (70S), whereas eukaryotic ribosomes are larger (80S).
Prokaryotic DNA is circular and may have plasmids, often consisting of a single chromosome, in contrast to eukaryotic linear chromosomes organized in pairs, showing more complexity.
Prokaryotic cells have a minimal cytoskeleton, while eukaryotic cells exhibit a well-developed cytoskeleton providing structural support and facilitating transport.

Reproduction Methods

Prokaryotic cells primarily reproduce asexually through binary fission, involving cell elongation, DNA replication, and subsequent division into two daughter cells.
Genetic exchange among prokaryotes can occur through conjugation (direct DNA transfer), transformation (uptake of free DNA), and transduction (DNA transfer mediated by viruses).
Eukaryotic cells typically reproduce asexually via mitosis, which includes chromosome duplication, division of the nucleus, and cytokinesis.
Sexual reproduction in eukaryotes involves meiosis, producing haploid gametes, with fertilization restoring the diploid state.
Some eukaryotic organisms can reproduce asexually through various methods such as budding, fragmentation, or spore formation.

Description

Test your knowledge on the differences between prokaryotic and eukaryotic cells. This quiz will assess your understanding of cell size, organelles, and genetic material. Explore the characteristics that differentiate these fundamental units of life.