Connect!Connect! Make a quick sketch of the Earth as a ball. Make a quick sketch of the Earth as a ball.

Add satellite dish, and radio towers, electric/phoneAdd satellite dish, and radio towers, electric/phone poles, phone towers… any structure that sends poles, phone towers… any structure that sends or receives information.or receives information.

Why do these structures stick up from theWhy do these structures stick up from the surface of the Earth?surface of the Earth?

Sketch a diagram of the structure of the cell membrane.Sketch a diagram of the structure of the cell membrane.

Add to the diagram to indicate how cells could send/receive info.Add to the diagram to indicate how cells could send/receive info.

What are the structures called that receive info?What are the structures called that receive info?

Recognizing SignalsRecognizing Signals

cells are able to receive cells are able to receive messages messages due to the cell membrane which has due to the cell membrane which has special receptor moleculesspecial receptor molecules

these receptors have these receptors have specific specific shapes which shapes which correspond to chemicals correspond to chemicals such as hormones that such as hormones that send messages to target send messages to target cellscells

Cells not meant to receive Cells not meant to receive a specific message simply a specific message simply do not have the do not have the corresponding corresponding receptorreceptor in their cell membranesin their cell membranes

Cell ReceptorsCell Receptors

Surface carbohydrates on cells serve as points of Surface carbohydrates on cells serve as points of attachment for other cells, infectious bacteria or attachment for other cells, infectious bacteria or viruses, toxins, hormones, and many other viruses, toxins, hormones, and many other molecules.molecules.

Lymphocytes, Lymphocytes, a type of white a type of white blood cell, blood cell, recognize recognize foreign foreign invaders by invaders by using using receptors.receptors.

Hormones Hormones influence influence target cells target cells by binding by binding to receptors, to receptors, which then which then influence influence the nucleus the nucleus to direct cell to direct cell activities in activities in a certain a certain way.way. NUCLEUS

HORMONE

TARGET CELL MEMBRANE

MESSAGE

For example, the hormone FSH is For example, the hormone FSH is sent from the brain sent from the brain all over the all over the bodybody of a woman through the blood. of a woman through the blood. Only the cells with the correct Only the cells with the correct receptors (in this case the cells of the receptors (in this case the cells of the ovaries) receive this message to ovaries) receive this message to mature eggs.mature eggs.

Pancreas cell

Stomach cell

Brain cell

Ovary cell

Chunk!Chunk!

How do cells receive messages?How do cells receive messages? How do the receptors work?How do the receptors work? What is a “target” cell?What is a “target” cell? Name some things that cells have Name some things that cells have

receptors for.receptors for. How do hormones work?How do hormones work? Give a specific example of a Give a specific example of a

hormone and its target cell.hormone and its target cell.

ImagesImages Cell membrane - Cell membrane - http://library.thinkquest.org/C004535/media/cell_membrane.gif Receptor - Receptor - http://www.unisa.edu.au/iwri/futurestudents/phdprojects/interf4.jpg Virus and lymphocyte - student.ccbcmd.edu/.../gensteps/u3fg2g.htmlVirus and lymphocyte - student.ccbcmd.edu/.../gensteps/u3fg2g.html Rest of images are self-generatedRest of images are self-generated