Question

lesson 2
levels of organization
directions: on the line before each definition, write the letter of the term that matches it correctly. each term is
used only once.

1. a cell that can become many different cell types

a. cell differentiation

1. a group of similar cells that work together to

b. stem cell
carry out a specific task
c. tissue

1. a group of different organs that work together to

d. organ
complete a series of tasks
e. organ system

1. the process by which cells becomes different

f. organism
types of cells

1. a group of organ systems that carry out all the

jobs needed for their survival

1. a group of different tissues working together to

perform a particular job
directions: circle the term in parentheses that correctly completes each sentence.

1. cells work together in a (multicellular/unicellular) organism.
2. a cell in a (multicellular/unicellular) organism must carry out all the activities that are

necessary to survive.

1. different types of cells in a multicellular organism have (different/the same)

chromosomes.

1. multicellular organisms are (eukaryotes/prokaryotes).

Explanation:

• 1 - 6:
• 1: Stem cells have the ability to differentiate into many different cell types.
• 2: Tissues are groups of similar cells working together for a specific task.
• 3: Organ systems are made up of different organs working together for a series of tasks.
• 4: Cell differentiation is the process by which cells become different types.
• 5: An organism is composed of organ systems that carry out all survival - related jobs.
• 6: Organs are formed by different tissues working together for a particular job.
• 7 - 10:
• 7: In multicellular organisms, cells work together. Unicellular organisms have only one cell.
• 8: In unicellular organisms, a single cell must carry out all survival activities.
• 9: Different types of cells in a multicellular organism have the same chromosomes (same genetic material, but different gene expressions).
• 10: Multicellular organisms are eukaryotes. Prokaryotes are usually unicellular.

Answer:

• 1 - 6:

1. B
2. C
3. E
4. A
5. F
6. D

• 7 - 10:

1. multicellular
2. unicellular
3. the same
4. eukaryotes