CELLS AND THEIR ENVIRONMENT: HOMEOSTASIS

LIFE’S BALANCING ACT If you are too hot or too cold your body temperature is out of balance

When we are too cold we shiver, it warms us up When we are too hot we sweat, it cools us down.

Sweating and shivering are the body’s response to extreme temperature. They help the body return to a temperature that is comfortable. Sweating and shivering are the body’s response to extreme temperature. The body is balanced

HOMEOSTASIS The balance that all living things must maintain is called HOMEOSTASIS.

Importance of CELL BALANCE Your body is made up of cells that must stay balanced. They need the right amount of materials to maintain the proper environment for your body.

T. Trimpe 2008 http://sciencespot.net/ Cell Challenge Scramble #1 T. Trimpe 2008 http://sciencespot.net/

MindStretcher: Identify the cell parts using the clues provided- 1. THORCSPALLO 2. LEEREACNMBML 3. OUVLEAC 4. LCOSNUULE 5. BDOGLYIOG 6. ORMCIATNH I’m needed for food. I’m the outside of an animal cell. You name it – I can store it! I make ribosomes. I work with the ER. I’m full of genetic information.

The answers are … I’m needed for food. 1. CHLOROPLAST I’m the outside of an animal cell. You name it – I can store it! I make ribosomes. I work with the ER. I’m full of genetic information. 2. CELL MEMBRANE 3. VACUOLE 4. NUCLEOLUS 5. GOLGI BODY 6. CHROMATIN

Potato Lab As a pair, pick up two cups off of the round table. Obtain two pieces of potato that are similar in size. Label one cup “salt” and the other “distilled water” with a permanent marker. Put one partner’s name on both cups.

Potato Lab continued… Fill 1/3 of a cup with salt solution and the other cup 1/3 full with distilled water. Make sure you have equal amounts. Measure the height, width, and length using a ruler. (in centimeters) Find the mass of the potato using the electronic scale and record it as indicated on the lab report. Place the piece of potato in the cup. Repeat with the other piece of potato. Both members of the pair need to diagram the lab. Be sure to include the variables and constants here. Place on the counter where indicated for your class.

What is the Difference Between Tap Water and Distilled? Tap water is directly supplied from the home faucet, while distilled water is water taken from any source that has gone through a distillation process. Tap water contains compounds, such as iron, chlorine, magnesium and natural minerals, that either are added by the public water system or have gotten in the water supply. Distilled water is in its purest form, with no bacteria or inorganic compounds.

Mind Stretcher 11-18-15 Why are some particles unable to pass through a cellular membrane? Answers may include: too big in size, semipermeable membrane, the particles fit what the cell needs. How is osmosis similar to diffusion? Osmosis is a special type of diffusion that involves water moving across the cellular membrane

Potato Lab Day 2 1. Measure the height, width, and length using a ruler. (in centimeters) 2. Find the mass of the potato using the electronic scale and record it as indicated on the lab report. 3. Write your “final” measurements in your data table & clean up your lab materials. 4. Complete the bottom two boxes of your lab sheet. It must be neat! Use complete sentences. 5. Turn in lab sheet and pick up a 3 x 3 (green) puzzle to complete at your seat quietly. * Finished? Try the other puzzle or work on your analogy/poem on the back of your other diffusion lab notes sheet.

What happened and Why? Make observations about the characteristics of each potato… Is it crispy or squishy? What color is it? Can you bend it? Where was there more pure water when this started? In the potato or in the cup? Think about both cases…and discuss them both in your paragraph. According to osmosis, where do the water molecules naturally want to move? (___ concentration to ___concentration) Finished? Pick up a bag with a green puzzle to complete after turning in your lab sheet!

Identify the cell organelles using the clues provided. 1. OIESOMBR 2. YSLSOMOE 3. TSYMAOLCP 4. ESLCUUN 5. NACITHIRMDOO 6. LECLLAWL I have a way with amino acids! I’m the garbage man! You can find everything in me! I’m the “brain” of the cell. I have all the “power” you’ll need. I’m found all “around” a plant cell.

The answers are … I have a way with amino acids! 1. RIBOSOME I’m the garbage man! You can find everything in me! I’m the “brain” of the cell. I have all the “power” you’ll need. I’m found all “around” a plant cell. 2. LYSOSOME 3. CYTOPLASM 4. NUCLEUS 5. MITOCHONDRIA 6. CELL WALL

Hypotonic, Isotonic, & Hypertonic

A solute is… the substance dissolved in a given solution.

Does the solvent or the solute contain more water? = salt = water

Hypotonic When the concentration of solute molecules outside the cell is lower than the concentration inside the cell cytosol, it is called Hypotonic.

Isotonic When the concentration of the solute are equal inside and outside the cell they are isotonic. (Equilibrium/Homeostasis)

Hypertonic When the concentration of solute molecules outside the cell is higher than the concentration in the cytoplasm, is a hypertonic solution.

Now, write the definition for each! Hypotonic- When the solution outside the cell is more concentrated than inside the cell. Hypertonic- When the solution outside the cell is less concentrated than inside the cell. Isotonic- the concentration of the solute are equal inside and outside the cell they are isotonic. (Equilibrium/Homeostasis)