6.4 - Multicellular Organisms Flashcards
True or False - Multicellular organisms have more working parts (cells) than unicellular organisms.
True
Name one of the largest organisms on Earth.
The Douglas fir tree is one of the largest organisms on Earth. It is 76 metres high and almost 3 metres in diameter! This giant tree is made up of many cells, which form the trunk, branches, leaves, and so on. MacMillan Provincial Park, British Columbia, is home to many giant Douglas firs. Most scientists believe these trees to be up to 800 years old!
True or False - Multicellular organisms use only some of their cells to perform life processes and meet their needs.
False
True or False - All multicellular organisms start as a single cell.
True
How do multicellular organisms grow?
When the one cell that the organisms starts with divides, the new cells do not move away from each other, but stay close to one another. The number of cells formed determines the size of the organism. As the number of cells increases, each cell becomes better able to perform one particular function within the organism.
Are multicellular organisms usually simple or complex? Give examples.
Multicellular organisms may seem simple, but they are very complex systems. The Hydra has specialized tentacles that catch food, but it also has different cells to digest that food. The goose has wings for flying and webbed feet for swimming. Different parts are made up of different specialized cells.
How do multicellular organisms work efficiently?
In complex multicellular organisms, cells are organized into groups that work together to perform specific jobs. When cells work together to perform one specific function, they are generally more efficient than one cell working on its own.
Define ‘cellular differentiation’.
Cellular differentiation is the process by which a cell becomes specialized to perform a specific function.
Define ‘tissue’.
A tissue is a group of differentiated cells that work together to perform a specific function.
Define ‘organ’.
An organ is two or more tissues that work together to perform one or more functions.
Define ‘organ system’.
An organ system is a group of organs that work together to perform related functions.
True or False - Cell specialization and cell differentiation are the same thing.
True
What are some important differentiated cells? Give an example on what one of them does.
Some of the most important differentiated cells include epithelial cells, muscle cells, nerve cells, and fat cells. For example: muscle cells are differentiated cells that contract.
What are the 4 basic types of tissue in animals? Give some examples of where they are.
The four basic types of tissue in animals are: epithelial tissue, muscle tissue, connective tissue, and nervous tissue. Blood is an example of connective tissue. In humans, epithelial tissue can be found covering the external surfaces of the body, and lining the surfaces of structures such as the mouth, heart, liver, and eyes.
Where are thin-walled plant cells and thick-walled plant cells commonly found?
In plants, tissues made from thin-walled plant cells are commonly found in the parts of the plant that carry water and nutrients. Tissues made from thick-walled plant cells are found
in the parts of the plant that provide structure.
