Skills 1-3: Cell division
Skill 1 - Why do cells have to divide? Which is more efficient, large cells or small cells?
Skill 2 - Which types of cells use mitosis to divide and which use meiosis?
Skill 3 - How are the chromosome numbers different? Which process produces identical cells and which produces variation (different cells)? (Use diagrams to answer the last question.)
Skill 1: Why do cells have to divide? Which is more efficient, large cells or small cells?
Skill 1: Why do cells have to divide? Which is more efficient, large cells or small cells?
Create a hypothesis...
Create a hypothesis...
An organism grows in size by increasing (choose one) the a) size or b) number of its cells ____________.
An organism grows in size by increasing (choose one) the a) size or b) number of its cells ____________.
Big picture #1:
Big picture #1:
As a cell grows, it increases its demand for DNA instructions, therefore a large cell must divide or die.
As a cell grows, it increases its demand for DNA instructions, therefore a large cell must divide or die.
Everyone will participate in this activity.
Everyone will participate in this activity.
Count off...one...two.
Count off...one...two.
Team one lines up on our side of the hallway.
Team one lines up on our side of the hallway.
Team two lines up on the other side.
Team two lines up on the other side.
Each team chooses a runner with good shoes on.
Each team chooses a runner with good shoes on.
The runner (mRNA) runs between the nucleus (Mrs. B) and each team member (ribosomes) delivering codes to "build proteins."
The runner (mRNA) runs between the nucleus (Mrs. B) and each team member (ribosomes) delivering codes to "build proteins."
When the ribosome receives its instructions, it should build its protein (follow the directions) and then sit down.
When the ribosome receives its instructions, it should build its protein (follow the directions) and then sit down.
The slower team will now divide into two cells, each with its own runner. Repeat the process above one more time.
The slower team will now divide into two cells, each with its own runner. Repeat the process above one more time.
Bigger is not always better. The nickel is bigger, but the smaller dime is worth twice as much. *Small cells are more efficient!*
Bigger is not always better. The nickel is bigger, but the smaller dime is worth twice as much. *Small cells are more efficient!*
In your Slides, draw a conclusion about the activity.
In your Slides, draw a conclusion about the activity.
Draw a conclusion: Which is more efficient at distributing instructions (choose one), a) smaller cells or b) larger cells? Write a 3-4 sentence explanation using observations of the activity.
Draw a conclusion: Which is more efficient at distributing instructions (choose one), a) smaller cells or b) larger cells? Write a 3-4 sentence explanation using observations of the activity.
The cell must _______________ or __________________!
The cell must _______________ or __________________!
Which bunny below needs more nutrients and makes more waste?
Which bunny below needs more nutrients and makes more waste?
Photo credit: Wikimedia Commons
Big picture #2: A larger cell increases the demand for nutrient acquisition and waste removal on the cell membrane.
Big picture #2: A larger cell increases the demand for nutrient acquisition and waste removal on the cell membrane.
Like Jack, below left, cells can also get overloaded by the need to get food and remove waste.
Like Jack, below left, cells can also get overloaded by the need to get food and remove waste.
We still have to deliver all of the packages, but what could we do to help Jack out?
We still have to deliver all of the packages, but what could we do to help Jack out?
We could divide the load onto two carts and let "Jill" help out. When a cell divides, it cuts each cell's work in half.
We could divide the load onto two carts and let "Jill" help out. When a cell divides, it cuts each cell's work in half.
Skill 2: Which type of cells use mitosis to divide and which use meiosis?
Skill 2: Which type of cells use mitosis to divide and which use meiosis?
Mitosis
Mitosis
Two identical somatic (body) cells
Two identical somatic (body) cells
An easy way to remember which cells use mitosis..."My toesies use mitosis." Since toes are body cells, body cells (somatic cells) use mitosis.
An easy way to remember which cells use mitosis..."My toesies use mitosis." Since toes are body cells, body cells (somatic cells) use mitosis.
Skill 3 - How are the chromosome numbers different? Which process produces identical cells and which produces variation (different cells)? (Use diagrams to answer the last question.)
Skill 3 - How are the chromosome numbers different? Which process produces identical cells and which produces variation (different cells)? (Use diagrams to answer the last question.)
Meiosis
Meiosis
Four different gametes.
Four different gametes.
Gametes are sex cells (sperm and eggs.)
Gametes are sex cells (sperm and eggs.)
An easy way to remember which cells use meiosis..."Meiosis is all about ME and how I got here." We all got here as a result of fertilization, or the combination of sex cells.
An easy way to remember which cells use meiosis..."Meiosis is all about ME and how I got here." We all got here as a result of fertilization, or the combination of sex cells.
Watch this video before going to the next page
Watch this video before going to the next page
Optional: If you prefer to record notes on paper, there is a copy below, which you may print.
Optional: If you prefer to record notes on paper, there is a copy below, which you may print.
