Science 7: Micro Life p.C-22 C35: A License To Learn Science 7: Micro Life p.C-22

Background 1 Scientific discoveries often follow the development of new tools and technologies. This is true in the case of infectious diseases Compound microscopes (with more than one lens) were invented around 1595. These first microscopes only magnified about 20 to 30 times but even this was enough to discover a new world of ideas.

Background 2 Italian physicist Giovanni Amici invented the oil-immersion microscope in 1840 which could magnify objects 6000 times. Today’s typical air microscopes are 400 x. Modern electron microscopes can magnify objects over 40,000 times.

Definitions 1 Epidemiologist: scientist who traces the spread of a disease through a population. Infection: exposure to a live disease. Vaccination: intentional exposure to a disease, usually not live, for the purpose of preventing that illness.

Definitions 2 Immune: people who are exposed to an infection but do not get sick, usually due to vaccination, previous exposure to the infection, and overall health. Symptom: outward sign of an illness like a cough, fever, headache, or rash. Carrier: someone who has a disease and can spread it without showing any symptoms.

Definitions 3 Vector: an organism (other than a person) that spreads disease-causing germs usually without getting sick itself, like animals and insects. For example, mosquitoes can spread Malaria, rats and fleas can spread Bubonic plague, and ticks spread Lyme disease. Quarantine: isolating people to try to prevent the spread of a disease.

Definitions 4 Cell: basic structural unit of all living things Nucleus: the “control center” of the cell

Microscope Parts

Proper Microscope Use Always carry microscope by the base & arm When focusing always go from low to medium to high magnification, not reverse. Clean lenses with lens paper only. When done with the microscope you should Turn the light off Lower the stage Set it to the lowest objective (magnification)

Magnification Compound microscopes have two lenses: the Eyepiece and the Objective. They each have their own magnification printed on them, but you find the total magnification by multiplying the numbers. Example: If eyepiece is 4x and the objective is 40x, what is the total magnification? 4 x 40 = 160x

Proper Slide Use A square piece of glass that goes on top of the glass slide is called a cover slip. A temporary (or wet) slide has living organisms (water) on it. Keep it as flat as possible and be careful! When you move a slide to the right it looks like it moves to the left (opposite).

Plant Cell 22k

Rose Leaf Stoma 3k

Snowflake

Cotton Fibers

Blood Cells

Insect

C35 Micro Analysis pC26 Copy & 1 paragraph each How does the microscope change the way the original object looks in real life? Compare how organisms you see look different between low and high power? Besides microscopes, list three other tools used by doctors and life scientists to study living things AND describe information those tools help scientists collect.