3.2.1.1 Structure of eukaryotic cells

• Fungi are eukaryotic.
• The structure of eukaryotic cells includes the cell-surface membrane, nucleus, mitochondria, chloroplasts, Golgi apparatus and vesicles, lysosomes, ribosomes, smooth and rough endoplasmic reticulum, cell wall, and cell vacuole.
• Lysosomes are sacs surrounded by a single membrane and are produced by the golgi.
• Lysosomes contain hydrolytic (digestive) enzymes.
• Cilia and flagella are long thin extensions that can move.
• Adjacent cells in plants are interconnected by fine strands of cytoplasm known as plasmodesmata for communication between cells.
• The cell wall provides structural support (stops it changing shape) and protection for the plant cell
• Rough ER is encrusted with ribosomes and hence is the site of protein synthesis.
• Ribosomes are made of protein and rRNA.
• Ribosomes are also found free in the cytoplasm.
• Smooth endoplasmic reticulum lacks ribosomes.
• The ER forms flattened sacs called cisternae.
• Golgi is a stack of flattened cisternae.
• Golgi allows collection, modification, sorting and packaging of molecules ready for transport to other parts of the cell.
• Some Golgi vesicles are lysosomes.
• Mitochondria are slightly larger than lysosomes and are surrounded by a double membrane or envelope.
• Mitochondria are the sites of aerobic respiration where ATP is produced.
• The cristae in mitochondria increase the surface area for the attachment of enzymes involved in ATP synthesis.
• The cristae project into the interior or matrix of the mitochondrion, which is the site of many enzymes involved in aerobic respiration.
• Cells rich in mitochondria are those that require a lot of energy.
• The nucleus is the largest organelle in the cell
• The nucleus is surrounded by a double membrane or envelope.

  The envelope is perforated by pores whose function is to enable the transport of mRNA and ribosomes out of the nucleus and hormones and nutrients in.
• The nucleolus is a densely staining region where ribosomal RNA is produced.
• Within the nucleus the DNA is combined with circular histone proteins and called chromatin.
• Chloroplasts

  Many of the sugar molecules formed during photosynthesis are stored as starch and starch grains can be found growing close to grana
• Chloroplasts

  Many thylakoids are stacked up to form grana
• Chloroplasts

  the stroma contains a circular DNA molecule, lipid droplets, starch grains, thylakoids and ribosomes
• What is located in the granum of chloroplasts?

  Enzymes for the light dependent stage of photosynthesis
• What is located in the stroma of chloroplasts?

  Enzymes for the light independent stage of photosynthesis located here
• Lysosomes contain enzymes used to digest damaged or infected cells and old organelles.
• Ribosomes are involved in protein synthesis.
• The cell wall of plants and algae is made up of cellulose.
• The nucleolus makes ribosomes.
• The nucleus controls the cells activities by controlling the transcription of DNA and has nuclear pores to allow substances to move between the nucleus and cytoplasm.
• The smooth endoplasmic reticulum (SER) synthesises and processes lipids.
• The inner membrane, outer membrane, matrix, and cristae of mitochondria are all parts of the mitochondria structure.
• Chloroplasts are structures that contain enzymes for the light dependent and light independent stages of photosynthesis.
• The inner membrane of mitochondria is folded to form cristae, which increase the surface area for the attachment of enzymes involved in ATP synthesis.
• The vacuole stores cell sap and helps maintain pressure inside the cell and keep it rigid. This stops the plant wilting. It is also involved in the isolation of unwanted chemicals inside the cell.
• The surrounding membrane of the vacuole is called the tonoplast