Gr.8 Science Review (Chapter 2)

Unicellular organisms are living things made up of single cells. This is ________

One type of unicellular organism is a _________. It produces most of the earths oxygen and lives in the ocean

• E coli bacteria

• Phytoplankton

• amoeba

• Diatom

Answer explanation

What does bacteria do

• There producers. They support life by spreading on other prey and making them filled with nutrients

• There decomposers. They support plant life by converting nitrogen in soil

True or False...

There are three ways unicellular organisms move

this is _______

Answer explanation

Proper Answers -

Though unclear, unicellular organisms do move in a variety of ways.

Cilia - tiny hairs that act like oars and propel it

Flagellum - looks like a tail, allows the cell to swim

Pseudopodia - changes the cell shape and forces the cytoplasm into extension

what are key points about amoebas

• Live in saltwater, fresh water, and wet vegetation

• they decompose other unicellular organisms

• An amoeba is a predator, it surrounds it prey and eats it

• They are omnivores

• They are moving with cilia constantly

True or False...

Specialized cells are found in unicellular organisms and help it function

This is _________

Answer explanation

Proper answer -

Multicellular organisms rely on a variety of types of cells to perform cellular functions. These types of cells are called specialized cells.

Why are cells so small

• Diffusion and Osmosis

• There organelles

Answer explanation

Proper Answer -

The limitation of a cells size is related to the processes of diffusion and osmosis.

Diffusion and osmosis need to go in and out of the cell providing energy or sorts. The shorter the distance they need to travel, the better the cell performs.

Are there multiple specialized cells in multicellular organism. Why / why aren't there multiple specialized cells

• (Yes)

  Because each cell helps do a different thing

• (no)

  Because each cell is made to do a numerous amount of jobs

• I Don't know

True or False...

The number of types of cells in a multicellular organism depends on the complexity of the organism. This is ________.

List the human cells...

(The six from textbook)

• vain cells

  muscle cells

  skull cells

  nerve cells

  skin cells

  fat cells

• muscle cells

  feet cells

  brain cells

  skin cells

  fat cells

  nerve cells

• Bone cells

  muscle cells

  brain cells

  nerve cells

  skin cells

  fat cells

• Bone cells

  muscle cells

  hair cells

  nerve cells

  skin cells

  fat cells