Eukaryotic cells and organelles

• Cell surface membrane description


  Membrane found on the surface of animal cells and just on the inside the cell wall of other cells. Its mainly made up of lipids and protein.

  
• Cell surface membrane function


  regulates the movement of substances into and out of the cell. It has receptor molecules on it, which allow it to respond to chemicals like hormones.
• Nucleus description


  Large organelle surrounded by a nuclear envelope which contains many pores. The nucleus contains chromosomes called a nucleolus.

  
• Nucleus function


  Controls the cells activities by controlling the transcription of DNA. DNA contains instructions to make proteins. The pores allow substances like RNA to move between the nucleus and cytoplasm. The nucleolus makes ribosomes.
• Mitochondrion description


  Have a double membrane.

  Inner membrane - folded to form structures called cristae. Inside is the matrix, which contains enzymes involved in respiration.

  
• Mitochondrion function


  Site of aerobic respiration where ATP is produced. They're found in large numbers in cells that are very active and require a lot of energy.
• Chloroplast description


  A small, flattened structure found in plant and algal cells. It's surrounded by a double membrane, and also has membranes inside called thylakoid membranes. These membranes are stacked up in some parts of the chloroplast to form grana. Grana are linked together by lamellae — thin, flat pieces of thylakoid membrane.

  
• Chloroplast function


  Site of photosynthesis. Some happen in the grana and other in the stroma.
• Golgi apparatus description


  Group of fluid filled, membrane-bound flattened sacs. Vesicles are often seen at the edges of the sacs.

  
• Golgi apparatus function


  Processes and packages new lipids and proteins and makes lysosomes.
• Golgi vesicle description


  A small fluid-filled sac in the cytoplasm, surrounded by a membrane and produced by the golgi apparatus.

  
• Golgi vesicle function


  Stores lipids and proteins made by the Golgi apparatus and transports them out of the cell.
• Lysosome description


  A round organelle surrounded by a membrane, with no clear internal structure.

  
• Lysosome function


  Contains digestive enzymes called lysozymes. These are kept separate from the cytoplasm by the surrounding membrane, and can be used to digest invading cells or to break down worn out components of the cell.
• Ribosome description


  A very small organelle that either floats free in the cytoplasm or is attached to the rough endoplasmic reticulum. It's made up of proteins and RNA. It's not surrounded by a membrane.

  
• Ribosome function


  site of protein synthesis
• Rough endoplasmic reticulum description


  A system of membranes enclosing a fluid-filled space. The surface is covered with ribosomes.

  
• Rough endoplasmic reticulum function

  Folds and processes proteins that have been made at the ribosomes
• Smooth endoplasmic reticulum description


  Similar to rough endoplasmic reticulum but with no ribosomes

  
• Smooth endoplasmic reticulum function


  Synthesises and processes lipids
• Cell wall description


  A rigid structure that surrounds plant cells. It's made mainly of the carbohydrate cellulose.

  
• Cell wall function


  supports cells and prevents them from changing shape.
• Cell vacuole description


  A membrane-bound organelle found in the cytoplasm. It contains sap and the surrounding membrane is called a tonoplast.

  
• Cell vacuole function


  Helps to maintain pressure inside the cell & keep the cell rigid. this stops the plant wilting. Also involved in the isolation of unwanted chemicals inside the cell.
• Tissue


  A group of similar cells that perform the same function.
• Organs


  Groups of tissues that work together to perform a specific function or related functions