Cell parts and Processes

-Surrounds the cell -Allows certain materials in and out The cell membrane

Jelly- like filling inside the cell It is mostly water. Cytoplasm

Nucleus -headquarters of the cell -regulates all cell activity -chromosomes inside Control Center

…I n the nucleus it looks like spaghetti! But when you look closely its - coiled tightly -forms “X” shapes Nucleus Chromosomes

And if you look at it even more closely, you see that it is coiled up DNA!

mitochondria breaks down food to make ATP Releases energy!

Vacuole: Stores water and other materials

Where plant cells trap sun light and use it to make food for the cell. photosynthesis Chloroplast- plants only

Cell walls – plants only Rigid structure surrounding plant cells. Provides support for the plant.

We have learned about some of the parts of a cell. Let’s see what they do to keep the cell or the organism alive. These “things they do” are Cell Processes

Transport Materials have to get in and out of a cell to meet the cells needs. There are 6 ways this can happen

The cell membrane is semi- permeable, but not everything goes through the same way.

Diffusion- movement of particles from an area of greater concentration to an area of lesser concentration Examples: the scent of perfume, food or something less pleasant food coloring, dye, flavors you taste

Osmosis is diffusion, but it applies only to water.

Water always leaves an area that’s more crowded with water molecules, and goes to an area where it’s less crowded with water molecules. High concentration of water molecules Low concentration of water molecules OSMOSIS means:

In this picture a red blood cell is put in a glass of distilled water (all water with no salt or sugar in it). Because there is a higher concentration of water outside the cell, water enters the cell by OSMOSIS. The cell bursts and dies

If it cant go through tiny openings, it goes through protein channels. There are two ways this happens: Passive transport and Active transport

Passive transport- requires no energy (works with diffusion)

Active Transport- requires energy (working directly against diffusion)

But what if the cell wants to take something in or out that won’t fit through the tiny openings or the protein channels? There are two ways: Endocytosis and Exocytosis

Endocytosis (engulf) – for materials too big to fit in through cell membrane

Exocytosis (opposite of Endocytosis ) for materials too big to fit out through cell membrane

Energy Production So where does the energy come from? There are two processes for energy production in plants: Photosynthesis CO2 + H2O + sunlight = glucose + O2 and Cellular Respiration glucose + O2 = energy + H2O + CO2

Photosynthesis Plants take in carbon dioxide and sunlight make food for the plant (glucose) oxygen is released

Cellular Respiration food and oxygen meet in mitochondria food is broken down energy (ATP) is released carbon dioxide is released

Cell Reproduction As a cell gets bigger, the outside is unable to keep up with the inside, because the inside grows a faster rate than the outside. They have to reproduce (divide) to stay alive The 2 types of cell reproduction are Asexual ( Mitosis) and Sexual (Meiosis)

Cell division in all cells except sex cells Mitosis (asexual) One makes Two DNA of offspring is identical to parent cell

Meiosis (sexual reproduction) One makes Four This is how sex cells, such as sperm and ovum, divide Offspring that result from sexual reproduction between 2 parents have different DNA from their parents

Now you should know : 8 cell parts the name and job 10 cell process and what they involve If you don’t know those things, watch the PowerPoint again and take notes.