Download CELLS, CELLS, CELLS

CELLS, CELLS, CELLS
A CELL is the basic unit of LIFE.
ROBERT HOOKE (1663) was the first person to see cells.
CELL THEORY:
A. ALL LIVING THINGS ARE MADE OF CELLS.
B. CELLS ARE THE BASIC UNITS OF STRUCTURE AND FUNCTION IN LIVING
ORGANISMS.
C. LIVING CELLS ONLY COME FROM OTHER LIVING CELLS
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TWO MAIN TYPES OF CELLS
1. PROKARYOTIC - simple cells (no nucleus) (e.g. bacteria)
2. EUKARYOTIC - complex more advanced cells (have organelles and a nucleus)
We are going to focus our study of cells on EUKARYOTIC CELLS (Plant & Animal Cells)
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All of the following organelles contained within the cell membrane of plant and animal cells are
suspended in a clear, jelly-like substance called CYTOPLASM.
STRUCTURE OF AN ANIMAL CELL
1. CELL MEMBRANE - outer covering of an animal cell
. protection and support
. helps control movement of materials into and out of cell
. "barrier with doors"
2. NUCLEUS - controls all cell activities
. "brain" of the cell
. contains CHROMOSOMES (made of DNA + protein)
which contain the "blueprint" for the animal's body
3. ENDOPLASMIC RETICULUM (E.R.) - cell's transportation system
. tubular passageways
. carries materials throughout the cell
4. RIBOSOMES - where proteins are made
. proteins are building materials for the animal's body and chemical messengers that
help regulate cell processes.
5. GOLGI BODY- stores and releases substances needed by
the cell (e.g. proteins)
6. MITOCHONDRIA- supply energy for the cell
. "powerhouse" of the cell
. convert energy from food (Glucose) into a form the body can use (ATP) through a
process called CELLULAR RESPIRATION
Chemical formula for Cellular Respiration is (C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + ATP)
(The mitochondria transforms ONE Glucose Molecule + 6 Oxygen Molecules INTO 6 Carbon
Dioxide Molecules + 6 Water Molecules + one ATP Energy Molecule)
7. VACUOLE- liquid filled sac that stores food and water
. not found in all animal cells
. if present in an animal cell, there will be a few small vacuoles
8. LYSOSOME - 3 functions
a. remove/recycle worn out parts
b. defend the cell against foreign invaders
c. break down large food molecules into smaller ones to be given to the
mitochondria to be broken down to release energy
The parts of a cell are called ORGANELLES. Organelles are specialized (each has its own job)
however, they all work together as a team to keep the cell functioning.
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structure of a plant cell
(different than Animal Cell)
1. CELL WALL - supports the plant cell
. helps plants stand upright
. made of CELLULOSE (i.e. fiber) a special type of carbohydrate
2. VACUOLE - one very large vacuole
. stores large amounts of water which causes TURGOR PRESSURE
. food is stored in a form called STARCH (another carbohydrate!)
Structure of a Plant Cell Continued…
3. CHLOROPLAST
. contain the green pigment CHLOROPHYLL
. allows plants to make their own food using the energy of the sun
through a process called PHOTOSYNTHESIS
Chemical formula for Photosynthesis is ( 6 CO2 + 6 H2O →SUNLIGHT→ C6H12O6 + 6 O2 )
(Sunlight is used to transform 6 Carbon Dioxide Molecules + 6 Water Molecules INTO
ONE GLUCOSE Molecule + 6 Oxygen Molecules)
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CELLULAR REPRODUCTION
Your body GROWS as you add more and more CELLS.
Your body produces more and more cells by a process called MITOSIS.
WHAT HAPPENS IN MITOSIS?
. The DNA in a cell's nucleus makes a COPY of ITSELF.
. The CELL then SPLITS into two cells.
. Each new cell is IDENTICAL to the first cell.
We will learn more about cellular reproduction a.k.a. mitosis later.
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LEVELS OF ORGANIZATION IN ANIMALS
1. CELL
. basic unit of life
2. TISSUE
. cells of similar structure and function joined together (e.g. muscle tissue)
3. ORGANS
. groups of tissues that work together to perform a specific function (e.g. the heart)
4. ORGAN SYSTEMS
. group of organs that work together to perform a specific function (e.g. digestive system)
5. ORGANISM
. a human being (like you!)