🎀Cytology🎀

• Cells

  The smallest living units of an organism with common features: cell membrane, cytoplasm, DNA
• Common features of all cells

  • Cell membrane
  • Cytoplasm
  • DNA
• Categories of cells

  • Eukaryotic cells
  • Prokaryotic cells
• Eukaryotic cells

  • Contain organelles including the nucleus and other special parts, found in plants and animals
• Prokaryotic cells

  • Don't have a nucleus or membrane-enclosed organelles, genetic material not contained within a nucleus, found in one-celled organisms like bacteria
• Organelle

  Specialized parts of a cell with unique jobs to perform
• Nucleus

  Contains DNA or genetic material, dictates cell's actions, chromatin is spread-out DNA, condenses into chromosomes during cell division, contains nucleolus where ribosomes are made
• Ribosomes

  Synthesize proteins, can float freely in cytoplasm or attach to endoplasmic reticulum
• Endoplasmic reticulum

  • Membrane-enclosed passageway for transporting materials, rough ER has attached ribosomes, smooth ER doesn't have attached ribosomes
• Golgi apparatus

  Receives proteins from the endoplasmic reticulum, customizes proteins into usable forms by folding or adding materials like lipids or carbohydrates
• Vacuoles

  Sac-like structures that store different materials
• In plant cells, the central vacuole stores water
• Proteins folding into usable shapes or adding other materials onto them

  1. Folding the proteins into usable shapes

  2. Adding other materials onto proteins such as lipids or carbohydrates
• Materials stored in vacuoles

  • Water
• Lysosomes


  Organelles that act as garbage collectors, taking in damaged or worn-out cell parts and breaking them down with enzymes
• Mitochondria


  Organelles that act as the powerhouse for both animal and plant cells, producing ATP molecules for energy through cellular respiration
• Cells that need more energy

  Have more mitochondria
• Cytoskeleton

  Structure that helps maintain the cell's shape, including microfilaments made of protein and microtubules which are thin hollow tubes
• Chloroplasts

  Organelles found in photoautotrophic organisms like plants, where photosynthesis occurs, containing chlorophyll pigment
• Cell wall


  Structure outside the cell membrane in plant cells that shapes, supports, and protects the cell
• Cilia

  Microscopic hair-like projections found in cells lining the respiratory tract in humans, helping trap inhaled particles and expel them
• Flagella

  Little tail-like structures found in some cells, like in some bacteria, that help the cell move or propel itself
• The only human cell that has a flagellum is a sperm cell
• Eukaryotic cells have a nucleus and membrane-enclosed organelles, while prokaryotic cells are unicellular organisms without these features
• Common features in all cells

  • Cell membrane
  • Cytoplasm
  • Genetic material
• Only plant cells have chloroplasts, but both plant and animal cells have mitochondria
• DNA

  deoxyribonucleic acid
• model of DNA was discovered by Watson and Crick
• DNA

  • double-stranded helix
  • each strand is made up of alternating sugars and phosphate groups
  • attached to sugars are base pairs
• Chromatin

  DNA wrapped around protein (histone)
• Chromosomes

  condensed chromatin
• base pairs of DNA

  • A=T
  • C=G
• human has 46 chromosomes in each cell, 23 pairs of chromosomes
• Centrioles

  aid in cell reproduction
• chromoplast

  contain red, orange, yellow, pigments that give flowers and fruits their color
• Leucoplast

  • colorless plastid
  • convert sugar to starch
  • better energy storage form