1.2 cells! - gandha.weebly.com
TRANSCRIPT
Chapter 1
1.2 Cells!
Cells, cells and more cells!
Living things are made up of cells!
Cells are the basic UNIT OF LIFE
Cells have different parts called “structures” that have different jobs.
We will mostly study animal and plant cells
Cell Facts…
How many cells do we have in our body?
50 – 100 trillion (that’s 50 million million!)
That means that if you lined all
your cells up one after another
they would stretch around the Earth
47 times!!!
If you could count 1 cell each second, it would take you 2600 years!!!
Cells
Plant and animal cells contain many of the same structures but there are some differences.
Only PLANT cells have
- cells walls and
- chloroplasts.
Let’s look at the various cell structures….
Cell Structures
• First let’s look at structures found in both animal and plant cells…
1. Cell Membrane- “the security guard”- like skin for the cell- it protects the cell- regulates particles coming in and out
Cell Structures
2. The Cytoplasm• “the jelly”• inside of the cell
contains a jelly-likesubstance
• supports all the structures in the cell
• also contains waterthat the cell needs!
Like Jello!
Cell StructuresSmaller structures in the cell that have a
specific function are called “organelles”
3. The Nucleus
• “the brain”
• controls the cell’s activities
• the DNA for the cell is also
found inside the nucleus
Cell Structures
4. Mitochondria
(singular = Mitochondrion)
• The “energy maker”
• Makes energy so the cell can carry out its activities
• Uses a process called
cellular respiration to make
energy
Cellular Respiration
How cellular respiration works:
We take in food (glucose) and our cells use this glucose to make ENERGY!
Glucose + Oxygen ENERGY + CO2 + H2O
Cell Structures
Protein plays many important roles in living things…
What is protein?o It’s an essential nutrient that WE need to
build muscles, hair, skin, and nails.
o CELLS need it to build various structures and carry out specific functions
Cell StructuresOur cells have
organelles in charge of making, moving and storing protein…
5. Ribosomes•little “protein factories”•they assemble the proteins•small round structures•found in the cytoplasm and on the ER
Cell Structures
• Looks like a fan or an accordian
• Network of channelscovered by a membrane
• Proteins pass through the ER after they are assembled by the ribosomes
6. Endoplasmic Reticulum (ER)
ER is always close to the nucleus!
Cell Structures
7. Golgi Body
• “like Fed-EX”
• Proteins go through the ER to the Golgi body
• Here the proteins are sorted, packed up in vesicles and sentaround (or out of) the cell
Cell Structures
8. Vacuoles• “storage sacs”
• Temporarily store
– Waste
– Water
– Nutrients
Large plant cell vacuole
Vacuoles in Plant & Animal Cells
Animals cells… Plant cells…
Have several small Have one large
vacuoles vacuole (usually)
Cell Structures
9. Lysosomes
• “recycling depots”
• Recycle organelles that have worn-out
• Have digestive enzymes that break down food, waste and worn-out cell parts
Cell Structures…Plants Only!
10. Cell Wall
• “the city wall”
• Surrounds the cell membrane
• Tough and rigid
• Gives the cell a box-like shape
• Main jobs:– Protects the cell
– Gives support
Cell Structures…Plants Only!
11. Chloroplasts• “food makers”
• Look like stacked green pancakes
• Trap the sun’s energy
• Make oxygen and food for plant in a process called “photosynthesis”
Photosynthesis
Energy + CO2 + H2O Food + O2
This is a very important process…
Plants take in carbon dioxide that we exhale and give us oxygen to
breathe!
RECAP!
Important differences between plant and
animal cells:
1. Plant cells have CELL WALLS
2. Plant cells have CHLOROPLASTS
3. Plant cells have much larger VACUOLES