Cell feature

• Nucleus structure

  Structure: Nuclear envelope (double membrane), Nuclear pores (allowing mRNA to leave the nucleus), Nucleoplasm (granular, jelly like material), Chromosomes (protein bound with linear DNA), Nucleolus (A small sphere inside which is the site of rRNA production and makes ribosomes)
• Nucleus Function

  • Function: Site of DNA replication and transcription (making mRNA), Contains all genetic code
• Endoplasmic reticulum


  Structure: Folded membranes called cisternae, Rough (have ribosomes on cisternae and is for protein synthesis), Smooth (synthesises and stores lipids and stores carbohydrates)
• Golgi apparatus and vesicles

  Structure: Folded membranes making cisternae, Secretory vesicles pinch off from the cisternae
• Golgi apparatus and vesicles Function

  • Function: Adds carbohydrates to proteins to form glycoproteins, Produces secretory enzymes, Secrete carbohydrates, Transport, modify and store lipids, Forms lysosomes
• Lysosomes


  Structure: Bags of digestive enzymes can contain 50 different enzymes
• Lysosomes


  • Function: Hydrolyse phagocytic cells, Completely break down dead cell, Exocytosis releasing enzymes to outside of cell to destroy material, Digests worn out organelles for reuse of materials
• Mitochondria

  Structure: Double membrane, inner membrane called the cristae, fluid centre called the mitochondrial matrix, loop of mitochondrial DNA
• Mitochondria

  • Function: Site of aerobic respiration, Site of ATP production, DNA to code for enzymes needed for respiration
• Ribosomes

  Structure: Small made up of two subunits of proteins and rRNA, 80S large ribosomes found in eukaryotic cells, 70S smaller ribosomes found in prokaryotic cells, mitochondria and chloroplasts
• Ribosomes


  • Function: Site of protein synthesis
• Vacuole (plant cell)

  Structure: Filled with fluid surrounded by a single membrane called a tonoplast
• Vacuole (plant cell)

  • Function: Make cell turgid and provides supports, Temp store of sugars and amino acids, Pigment may colour petals to attract pollinators
• Chloroplasts

  Structure: Surrounded by double membrane, Contains thylakoids (folded membranes embedded with pigment), Stack of thylakoids called grana, Fluid filled stroma containing enzymes for photosynthesis
• Chloroplasts

  • Function: Site of photosynthesis
• Cell wall (PLANTS and FUNGI)


  Structure: Plants - made of microfibrils of the cellulose polymer, Fungi - made of chitin, a nitrogen containing polysaccharide
• Cell wall (PLANTS and FUNGI)

  • Function: Provides structural strength to the cell
• Plasma membrane

  Structure: Phospholipid Bilayer molecules embedded within and attached on the outside (protein carbohydrates and cholesterol)
• Plasma membrane

  • Function: Controls entrance and exit of molecules