Unit 37

Lesson Aims

Outline Unit 37 Describe how nutrients, oxygen and water enter and leave cells by diffusion and osmosisDescribe how body obtains and uses energy

Learning outcomes

Three tasks within assignment :Understand biological principles in relation to beauty therapyUnderstand the chemical processes that occur in the body and in beauty therapyUnderstand the principles of physics in relation to beauty treatments in the salon.

Biological Principles

29/02/16 28/03/16

Chemical Processes

28/03/16 25/04/16

Principles of physics

25/04/16 23/05/16

Composition of cell membrane and functions

Cell Membrane

The cell membrane is also called the plasma membrane and is made of a phospholipid bi-layer.T he phospholipids have a hydrophilic (water attracting) head and two hydrophobic (water repelling) tails. The head of a phospholipid is made of an alcohol and glycerol group, while the tails are chains of fatty acids . Phospholipids can move sideways and allow water and other _non-polar molecules to pass through into or out of the cell. This is known as simple passive transport because it does not require energy and the water or molecules are moving with the concentration gradient.

Another type of lipid in the cell membrane is cholestrol that makes the membrane more fluid. Embedded in the phospholipid bilayer are proteins that also aid in diffusion and in cell recognition. Proteins called integral proteins go all the way through the bilayer, while peripheral proteins are only on one side. Integral proteins are also called x proteins. Large molecules like proteins or carbohydrates use proteins to help move across cell membranes. Some of the membrane proteins have carbohydrate parts attached to help cells in recognise each other and certain molecules. List 4 functions of the cell or plasma membrane:a. Excretion of wasteb. Selecting transportc. Structural supportd. Cell signaling

Please watch the video and write a definition of - Osmosis - Diffusion- Active transport

Isotonic - There is no change to the cell size, the concentration particles are the same inside and outside the cell

Hypertonic - The concentration of particles are higher outside the cell than inside the cell. Water will leave the cell in an attempt to dilute the outside concentration

Hypotonic-The concentration of particles are lower outside the cell than inside the cell. Water will enter the cell in an attempt to dilate the inside concentration

Group workFind examples within the body of how nutrients, oxygen and water leave the cells by diffusion, osmosis and active transport

How the body obtains energy

There are six main forms of energy which include the following – Heat Chemical ElectromagneticNuclear Mechanical Electrical

Our bodies use Chemical Energy

There are two states in which energy can exist

Potential EnergyStored energy.Energy that could be used.

Kinetic EnergyEnergy of Action or Motion.Energy that is being used.

Energy can be changed from one form or state into another. Changes in the forms or states of energy are called energy conversions or transformations.

Our body converts starches, sugars, fats and even proteins (chemical energy) that we eat into energy for our bodies’ daily functions (mechanical and heat or thermal energy).

During the digestion process, how does the body breaks down foods into smaller organic compounds?The teeth first break down the food physically into smaller pieces. The movement of the stomach and intestines also help physically break the food.Proteins are broken down chemically by pepsin in the stomach into amino acids.Carbohydrates are broken down chemically into sugars (monosaccharides) by enzymes found in saliva in the mouth and by enzymes in the small intestine.Fats are broken down into fatty acids by bile from the liver in the small intestines.These smaller molecules are transported into body cells and then go through several chemical processes that break the molecular bonds to produce ATP, a primary storage form and source of energy in the body. These chemical processes occur in the cytoplasm and mitochondria in the cells.

Our Energy Use Must be Balanced!

The amount of energy that comes into our body should be equal to the amount of energy that we use.If it is not, we STORE the extra energy that is not used.The main way the body stores excesss energy is in the form of fat.

Group Work - Design a power point to discuss points on page 12 A Group - Skin B Group - Kidneys C Group - Skin Needs to be completed 01/03, and uploaded on itslearning