Cell structure

• What is a nuclear envelope?

  A double membrane that surrounds the nucleus
• what are nuclear pores?

  Tiny holes in the nuclear envelope that act as gateways for materials to move in and out
• What is the nucleolus?

  A small, round structure in the nucleus that assembles together ribosomes
• What are vesicles?

  Small fluid-filled sacs that transport substances around inside a cell
• What are ribosomes made up of?

  RNA and proteins
• What is the rough endoplasmic reticulum?

  • a system of folded membranes that has ribosomes on its outer surface
  • The RER is where proteins are processed and packaged into vesicles
• How does the structure of the rough endoplasmic reticulum help enable the synthesis of proteins?

  • has a large surface area
  • Has ribosomes
• What is the smooth endoplasmic reticulum?

  • a system of membranes with no ribosomes on its outer surface
  • The SER is where carbohydrates and lipids are secreted and packaged into vesicles
• What is the Golgi apparatus?

  • stores and modifies proteins and lipids. It the packages them into vesicles for transportation
  • Some of the proteins packaged are enzymes. These enzymes are used to form lysosomes
• What is a lysosome?

  A membrane-bound organelle that releases lysozyme enzymes
• What is the function of the mitochondria?

  site for aerobic respiration and ATP
• A=matrix. B=inner membrane

  
• What is the function of the vacuole in a plant cell?

  • supports the plant by making cells turgid
  • Also stores sugars and amino acids which can act as a temporary food store
• What are plant cell walls mainly composed of?

  the polymer cellulose
• What are fungal cell walls mainly composed of?

  Chitin
• What are thylakoids?

  Flattened sacs in the chloroplast containing the pigment chlorophyll
• What are grana?

  Stacks of thylakoids found in the stroma of a chloroplast
• What are prokaryotic cells?

  Single -celled organisms that don’t contain any membrane-bound organelles
• What are the ribosomes in eukaryotes and prokaryotes called?

  Eukaryotes: 80S

  Prokaryotes: 70S
• What is the function of the cell wall?

  • protection
  • Maintains cell shape
  • Prevents cell from bursting
• What are plasmids?

  Additional, small, circular pieces of DNA in prokaryotic cells
• What is the role of plasmids?

  Used in genetic exchange between prokaryotic cells
• What is the function of the flagella?

  • to move towards food
  • To move away from danger
• What is the function of the capsule?

  • helps keep water inside the cell
  • Makes it harder for white blood cells to destroy the cell
• What does acellular mean?

  Not made up of cells
• viruses are…

  • acellular
  • Non- living
• A= attachment proteins

  B= lipid envelope

  C= protein capsid