Download Section 1-1 Notes pgs. 16-22 Cells are the basic units of structure

Section 1-1 Notes pgs. 16-22
Cells are the basic units of structure and function in living things.
Pgs.17-19
The microscope made it possible for people to discover and learn about cells.
A microscope is an instrument that makes small objects look larger.
First people to Observe Cells
Robert Hooke – Used a compound microscope to look at a piece of thin sliced cork and called it
a cell.
Anton van Leeuwenhoek – Used a simple microscope to look at pond water and said he saw
animalcules.
The Cell Theory pg. 20
Theodor Schwann other scientists developed the cell theory.
1. All living things are composed of cells.
2. Cells are the basic unit of structure and function in living things.
3. All cells are produced from other cells.
How a light Microscope Works (pages 21-22)
Magnification is the ability to make things look larger than they are.
The lenses of the light microscope make an object look larger by bending the light the passes
through them.
In a convex lens, the center of the lens is thicker than the edges.
Resolution is the ability to clearly distinguish the individual parts of an object.
Electron Microscopes (page 22)
This is a microscope that uses a beam of electrons to examine a specimen.
The electron microscope has a better resolution then a light microscope
Looking Inside Cells Section 1-2 pages 23-31
Organelles are tiny cell structures inside a cell that carry out specific functions within the cell.
Cell Wall: 24pg
Cell Wall
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Nonliving material that surrounds plant cells.
Plant cells have cell walls
The cell wall is made of cellulose.
Function of the cell wall is to protect and support the cell.
Cell Membrane (24-25pgs)
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All cells have cell membranes
Function of the cell membrane is to control what substances come into and out of a cell.
Plant cell membranes are located inside the cell wall.
Animal cell membranes are located on the outside of the cell.
Nucleus (25-28pgs)
 Structure - The largest organelle in the cell. It is dark and round, and is surrounded by a
double membrane called the nuclear envelope/membrane. In spots the nuclear
envelope fuses to form pores which are selectively permeable.
 The nucleus contains genetic information (DNA) on special strands called Chromatin
that forms chromosomes.
 Function - The nucleus is the "control center" of the cell, for cell metabolism and
reproduction.
Organelles in the Cytoplasm
Cytoplasm – clear, gel-like fluid that is between the cell membrane and the nucleus.
Mitochondria - "powerhouse" of the cell. The mitochondria releases food energy from food
molecules to be used by the cell.
Ribosomes – Produce proteins.
E.R. Endoplasmic Reticulum - canals filled with fluid. They carry materials (proteins) throughout
the cell.
Golgi Bodies - (they look like pancakes!). Receive proteins and other materials from the E.R.,
package them, and send them to other parts of the cell or outside the cell.
Chloroplasts- Which contains the green pigment chlorophyll. This is important in the process
of photosynthesis.
Vacuoles -They can store materials such as food, water, sugar, minerals and waste products.
Lysosomes - containing strong digestive enzymes which when released can break down worn out
organelles or food. The lysosome is also known as a suicide sac.