Eukaryotic cells

Definition

Eukaryotic cells are complex cells that contain a nucleus and other membrane-bound organelles, which allows them to perform specialized functions. They are larger and more advanced than prokaryotic cells, and they can be found in a variety of organisms, including plants, animals, fungi, and protists. The presence of a defined nucleus is a key feature that distinguishes eukaryotic cells from their simpler counterparts.

5 Must Know Facts For Your Next Test

1. Eukaryotic cells can be unicellular or multicellular, allowing for complex organisms like humans as well as single-celled organisms like yeast.
2. The DNA in eukaryotic cells is organized into linear chromosomes within the nucleus, as opposed to the circular DNA found in prokaryotic cells.
3. Eukaryotic cells often have a cytoskeleton that provides structural support and helps with cell movement and division.
4. Plant eukaryotic cells contain chloroplasts for photosynthesis, while animal cells have lysosomes for digestion.
5. Cell division in eukaryotes typically occurs through mitosis or meiosis, which are more complex processes than binary fission in prokaryotes.

Review Questions

• How do eukaryotic cells differ from prokaryotic cells in terms of structure and function?
  • Eukaryotic cells differ from prokaryotic cells primarily in their complexity. Eukaryotic cells have a defined nucleus that contains their DNA, while prokaryotic cells do not have a nucleus and their DNA is free-floating in the cytoplasm. Additionally, eukaryotes possess membrane-bound organelles such as mitochondria and endoplasmic reticulum, enabling them to perform specialized functions that are absent in prokaryotes.
• What roles do organelles play in the functionality of eukaryotic cells?
  • Organelles in eukaryotic cells are crucial for maintaining cellular functions and efficiency. Each organelle has specific roles; for instance, mitochondria generate energy through cellular respiration, ribosomes synthesize proteins, and the endoplasmic reticulum assists in the production and transport of biomolecules. The presence of these specialized structures allows eukaryotic cells to carry out complex processes essential for growth, reproduction, and response to environmental changes.
• Evaluate the significance of the cytoskeleton in eukaryotic cells and its impact on cellular functions.
  • The cytoskeleton is vital for the overall structure and function of eukaryotic cells. It provides mechanical support, helping the cell maintain its shape and resist deformation. Additionally, the cytoskeleton is involved in intracellular transport, enabling organelles to move within the cell, and it plays a key role during cell division by ensuring proper segregation of chromosomes. The dynamic nature of the cytoskeleton also allows for cellular movements, such as muscle contraction or amoeboid movement in certain protists.

Related terms

Prokaryotic cells: Simpler, smaller cells that lack a nucleus and membrane-bound organelles, primarily represented by bacteria and archaea.

Organelle: Specialized structures within a cell that perform distinct functions, such as mitochondria for energy production and ribosomes for protein synthesis.

Cytoplasm: The jelly-like substance within the cell membrane that surrounds the organelles and is where many cellular processes occur.