1. Unit 3 lesson 5 Homeostasis and Cell Processes

2. I. Homeostasis https://youtu.be/6fhbbFd4icY A. Maintaining Balance
Homeostasis= maintenance of an internal balance of conditions in a changing external environment
Need to;
Obtain energy
Use energy
Make new cells
Exchange materials
Eliminate wastes
In unicellular organisms the cell membrane will regulate homeostasis by monitoring what goes in and out of the cell

3. xylem carries water in plants from “roots to shoots”
multicellular organisms use the cardiovascular system to transport materials throughout the body
carry wastes away and bring nutrients to cells
xylem carries water in plants from “roots to shoots”
phloem carries “food” glucose from leaves to roots (shoots to roots)

4. II Cell Energy https://youtu.be/eo5XndJaz-Y A. Photosynthesis
Photosynthesis= process by which plants, algae, & some bacteria use sunlight, carbon dioxide (CO2) to make food (sugars)
Chlorophyll is a pigment that absorbs energy
Gives plants their green color
Found in the chloroplasts
Plants have cells that open and close on the bottom of their leaves called stomata
Stomata allow CO2 to enter the plant

5. Roots of the plant allow water to enter the plant
CO2 plus water with the energy from light creates glucose (sugar) and oxygen
Glucose can be stored as starch that we eat in plants
Oxygen is released out of plants through the stomata for us to breath
The energy from sun is not “used” it is needed to make allow the reactions to happen

6. B. Cellular Respiration
Cellular respiration= process which cells use oxygen to produce energy from food
It is NOT breathing
Breathing gives the oxygen needed to run cellular respiration
Glucose (food) is broken down into CO2 & H2O (water) using O2 (oxygen)
ATP is made (ENERGY for the cell)
CO2 released goes to plants for photosynthesis
Takes place in the mitochondria
“Mighty” mitochondria or the powerhouse of the cell

7. Plants also undergo cellular respiration in their mitochondria to release the energy in the glucose that they made during photosynthesis
Plants use CO2 to make sugar & release O2= cycle
Animals use O2 to break down sugar and release CO2 = cycle

8. C. Fermentation
Fermentation= the breakdown of food without the use of oxygen
Cells need ATP to function & live
When there is no available oxygen and the cell is working it must make ATP using fermentation
Lactic acid is produced in our cells= causes muscles to be sore
Alcoholic fermentation is used in baking with yeast
Holes in the bread is from the CO2 being released

9. III. Cell division A. Purpose
To reproduce
cells must copy their DNA before they reproduce
binary fission asexual reproduction in which a prokaryote copies it’s DNA and splits in two
mitosis= eukaryotic cellular division
DNA condenses into chromosomes to allow the cell to divide into 2 identical cells

10. To grow and repair damaged cells
mitosis allows for multicellular eukaryotes to replace cells and grow

11. IV. Exchange with the environment. A
IV. Exchange with the environment A. Diffusion- passive transport
The cells have to get rid of waste products and take in materials needed to live
Semipermeable membrane= allows certain substances in and out of the cell
The cell membrane
Particles travel from where they are crowded (high concentration) to where they are less crowded (low concentration)= diffusion
Food color in water will move throughout until all of the water is colored

12. B. Osmosis- passive transport https://youtu.be/7-QJ-UUX0iY
Osmosis= the diffusion of water through cell membranes
Water is made of particles called molecules
Pure water has a lot of water molecules
Kool-Aid would have less water molecules than pure water because the sugar takes up some of the water molecule space
Like diffusion= water will move from a high concentration (crowded space) to a low concentration (less crowded space)
Without osmosis our body would not be able to keep the right amount of water in our cells
Plants would wilt without being able to gain or lose water

13. C. Moving small particles
Small particle will move into and out of the cell membrane through proteins that make “tunnels”
Passive transport does NOT use energy
Particles move from high concentration to low concentration (osmosis)
Active transport DOES USE energy
Moves from low to high (like a salmon swimming upstream)

14. D. Moving large particles- active transport
Endocytosis= active transport process in which the cell will take in a particle
Cell comes into contact with what it is going to bring in
Cell membrane wraps around the particle
A vesicle pinches off inside of the cell

15. Exocytosis: the active transport process in which something is being released to the outside of the cell
Particle such as waste must leave the cell
Vesicle travels to the edge of the membrane
Cell releases the particle out