16. Objects under a microscope are always
upside down and backwards.
17. Because objects are upside down and
backwards, one has to move a slide
the OPPOSITE of where one wants to
move an object.
I must move the
slide this way
If i want to move the
organism this way
18. When wet-mounting a specimen on a
slide, the cover-slip must be lowered
at an angle to prevent air bubbles.
19. To stain a specimen, place a paper towel at
one side of the slip cover. Add the dye stain
at the opposite end. Capillary action will
“pull” the dye through, staining the
specimen.
20. A microscope’s field of view is the diameter
of the microscope’s circle. Knowing the
field of view can be used to determine the
size of microorganisms.
21. If this microscope’s field of view under low
power is 1000um, what is the size of the
organism?
1000um
22. If this microscope’s field of view under low
power is 1000um, what is the size of the
organism? ~200um
1000um
30. The goal of the lab is to model how a cell
uses diffusion to maintain homeostasis.
31. 1. We put starch and
What we did: glucose inside a piece of
plastic called dialysis
tubing.
2. We tied both ends tight
with string.
3. We place several drops
of iodine starch indicato
into a cup of water.
32. We placed the dialysis tube in cup to
see what happens:
33. • The will
Our predictions: of the
dialysis tube because
the
.
• The will
the tube because
the
.
• The will stay
inside the tube because
the .
.
35. The starch molecules were too large to diffuse out. Inside
dialysis tube turned blue-black (purple-black) because the
starch indicator (iodine) diffused into tube & change the
starches’ color.
36. A sample of the liquid from outside the
tubing turned glucose indicator orange
because the small glucose diffuse out.
41. Diffusion: the movement of molecules
from areas of high concentration to
areas of low concentration without
using energy.
42. Diffusion: the movement of molecules
from areas of high concentration to areas
of low concentration without using energy.
More Less
sugar sugar
More
sugar Less sugar
97%
Cell has Surrounding has
97% 92% water
water
Cell has inside
surrounding
94%
Area has
water
96% water
inside
43. Diffusion: molecules move from high
concentration to low concentration
without using energy.
More Less
sugar sugar
More
sugar Less sugar
97%
Cell has Surrounding has
97% 92% water
water
Cell has inside
surrounding
94%
Area has
water
96% water
inside
44. Diffusion: molecules move from high
concentration to low concentration
without using energy.
Cell has Surrounding has
100% 6% water
water
surrounding Cell has inside
Area has 6% salt
100% water inside
93. The human body is like a machine
with many complicated systems.
All the systems must work together
to maintain homeostasis.
94. All of our organ systems work together
to maintain our homeostasis.
Examples:
• Our muscular system moves our body. It gets
Oxygen from our respiratory system in order
to produce ATP. The circulatory system brings
the oxygen to the muscles. Our excretory
system sweats to keep the muscles cool (from
over heating).
95.
96. When we’re very active. All of our
systems speed-up to keep up with the
increased activity.
