Keystone Biology Remediation A4: Homeostasis and Transport Assessment Anchors: • to describe how the structure of the plasma membrane allows it to function as a regulatory structure and/or protective barrier for the cell (A.4.1.1) • to compare the mechanisms that transport materials across the plasma membrane (i.e. passive transport – diffusion, osmosis, facilitated diffusion; and active transport – pumps, endocytosis, exocytosis) (A.4.1.2) • to compare how membrane-bound cellular organelles (e.g. endoplasmic reticulum, Golgi apparatus) facilitate the transport of materials within the cell (A.4.1.3) • to explain how organisms maintain homeostasis (e.g. thermoregulation, water regulation, oxygen regulation) (A.4.2.1) Unit Vocabulary: active transport extracellular marker protein carrier (transport) proteins facilitated diffusion osmosis concentration Golgi apparatus passive transport concentration gradient homeostasis phospholipid bilayer diffusion homeostatic mechanism plasma membrane endocytosis impermeable pumps (ion or molecular) endoplasmic reticulum intracellular transport protein (pump) exocytosis Assessment Anchor: Describe how the structure of the plasma membrane allows it to function as a regulatory structure and/or protective barrier for the cell (A.4.1.1) The Cell Membrane (A.K.A. Plasma Membrane) The main function Selective permeability is Is composed mainly is to regulate what Individual the term that describes of phospholipids enters and leaves phospholipid: the fact that the that form a bilayer. the cell. membrane allows some materials to pass through while preventing others. When molecules move two other through the components phospholipids portion of the membrane it is cholesterol to help proteins called simple the membrane diffusion. maintain its fluidity Molecules Molecules that pass that don’t freely pass freely The special type channel pumps marker through the through the of diffusion proteins proteins membrane membrane where water are small are large moves across and/or and/or the membrane is used for the used the used for cell nonpolar. polar. osmosis. process of process of identification facilitated active diffusion transport Examples are CO2 & Examples are Glucose is an example of a Ions are examples of particles O2 (small) and proteins (large) molecule transported this way. transported this way. lipids (nonpolar) Assessment Anchor: Compare the mechanisms that transport materials across the plasma membrane (i.e. passive transport – diffusion, osmosis, facilitated diffusion; and active transport – pumps, endocytosis, exocytosis) (A.4.1.2) Moving Materials across the Plasma Membrane can be passive can be active energy in the form of ATP which does not which does require require because molecules because particles are and includes move down the being moved against concentration the concentration gradient gradient endocytosis exocytosis active transport (simple) diffusion where osmosis, facilitated (pumps) particles move through the which is diffusion , which is phospholipid part of the the diffusion through membrane diffusion of channel proteins water of solid particles of liquid droplets is phagocytosis is pinocytosis Ions are an example examples of substances an example of a An example is a of a substance transported in this manner bacterial cell being transported in this substance are CO2(small), O2(small), engulfed by a white manner. and lipids (nonpolar) transported in this manner is glucose blood cell Assessment Anchor: Compare how membrane-bound cellular organelles (e.g. endoplasmic reticulum, Golgi apparatus) facilitate the transport of materials within the cell (A.4.1.3) Smooth ER is involved in the The nucleus contains chromosomes made of DNA and protein. production of lipids and the The DNA contains the code that specifies the order that the The code for the production of a particular detoxification of poisons. amino acids should be placed in to make a particular protein. protein is found in the chromosomes which are located in the nucleus. Proteins are produced on the ribosomes. Proteins are produced on the ribosomes. Lysosome The proteins are sent for further s contain processing to the rough endoplasmic digestive reticulum. enzymes. Proteins are transported in vesicles. The proteins are then packaged for their final destination in the Golgi complex. Rough ER modifies proteins made on Proteins are transported in vesicles. the ribosomes. Some Some proteins If the Some proteins will will be proteins vesicles speed up incorporated are to be develop chemical into the secreted into reactions plasma secretion from the organelles within the membrane. cell (such used for cell. These Examples are: The Golgi complex as digestion receives proteins within the are called hormones), • marker from the rough ER cell and enzymes. and sorts and the vesicle proteins packages them into must fuse are called • channel vesicles. with the lysosomes proteins . plasma • transport membrane. proteins (pumps) Assessment Anchor: Explain how organisms maintain homeostasis (e.g. thermoregulation, water regulation, oxygen regulation) (A.4.2.1) Homeostasis maintaining constant internal conditions Examples include: Thermoregulation Water regulation Oxygen regulation Definition: maintaining Definition: maintaining the Definition: maintaining a constant body temperature constant amount of water in the consistent concentration of oxygen body in your cells and bloodstream One way living things achieve this: sweating when hot or One way living things achieve One way living things achieve shivering when cold this: urinating very little when this: breathing faster when dehydrated exercising Possible consequence of problem with regulatory Possible consequence of Possible consequence of problem process: Enzymes only problem with regulatory with regulatory process: If cells function properly in a narrow process: If water is retained in can’t get enough oxygen to carry temperature range. the body, it can cause swelling. out cellular respiration, they die. .