Animal and Plant Cells: Similarities and Differences

Similarities between Animal and Plant Cells

• Both are Eukaryotic Cells
  • Have a membrane-bound nucleus.
• Membrane-bound Organelles
  • Nucleus: Houses genetic information.
  • Cytoplasm: Entirety of cell content within the cell membrane.
  • Cytosol: Part of the cytoplasm not occupied by organelles.
  • Cell Membrane: Semi-permeable barrier controlling cell's biochemistry.
  • Mitochondria: "Powerhouses" of the cell, perform aerobic respiration converting glucose to ATP.
  • Rough and Smooth Endoplasmic Reticulum (ER)
    • Rough ER: Covered with ribosomes, translates RNA into proteins.
    • Smooth ER: Lipid synthesis.
  • Golgi Apparatus: Modifies proteins.
  • Peroxisomes: Metabolize waste.

Differences between Animal and Plant Cells

Structural Differences

• Cell Wall
  • Present in plant cells, made of cellulose.
  • Provides rigidity, resulting in fixed angular shapes for plant cells.
  • Animal cells lack a cell wall, leading to round and irregular shapes.

Energy Acquisition

• Plants
  • Autotrophs: Produce own food via photosynthesis in chloroplasts.
    • Chloroplasts: Contain chlorophyll, capture light for photosynthesis.
• Animals
  • Heterotrophs: Ingest food to obtain sugars for energy.

Vacuoles

• Plant Cells
  • Large central vacuole, can occupy up to 90% of the cell's volume.
  • Functions: Fill space, digestion, nutrient storage, waste degradation.
• Animal Cells
  • Smaller vacuoles, multiple, not as space-occupying.

Cytoskeleton and Organelles

• Cytoskeleton
  • Present in both, composed of microtubules, intermediate filaments, and microfilaments.
  • Different arrangement in plant vs. animal cells.
• Centrioles
  • Present in all animal cells.
  • Only in lower plants (e.g., Chlamydomonas) in plant cells.

Mobility Structures

• Flagella
  • Present in some animal cells (e.g., human sperm).
  • Only reproductive plant cells (e.g., bryophyte sperm) have flagella.
• Cilia
  • Common in animal cells (e.g., human respiratory system).
  • Rare in plant cells.

Lysosomes

• Animal Cells
  • Clearly defined lysosomes.
• Plant Cells
  • Debate on presence; some argue similar structures exist.

Cell Connectivity

• Plasmodesmata
  • Channels in plant cells connecting two cells.
• Gap Junctions
  • Analogous structure in animal cells, connects cytoplasm of adjacent cells.