11-02-10

• IN

• Why don’t plant cells explode in a hypotonic solution?

• Did the onion cell shrink in the salt solution?

• Explain the reason for the change in the onion cell after you added the salt solution. (name the process)

11-02-10

• Through• Notes• Part A Circulatory

system

• OUT • None

Cell Processes

Passive transportPassive transport is a means of moving substances across the cell membrane. Unlike active transport, this process does not require energy. Two main kinds of passive transport are diffusion and osmosis.

Active transportActive transport is a means of moving substances across the cell membrane by using cellular energy. Goes against concentration gradient

Egg in sugar solution

Egg in water solution

Observe and record any notes

• Hypertonic Hypotonic

• Building molecules

Answer the following questions

• 1. What evidence did you collect that indicates that the external environment affects the internal environment?

• 2. In the previous activities, how did the egg serve as a model of how cells function as containers in living organisms?

• 3. What do eggs, animal cells, plant cells, and the human body have in common?

• 4. Based on your observations of cells, what might have been happening in Josh’s body in the story when he…

• First became hot and started to sweat• Became thirsty• Went to the house for refreshments• Returned to work

• Open your book to page 165• Watch video on circulatory system