1.1: Life's Level of Organization

Question 1

atom

Answer 1

Atoms are fundamental units of all substances. This is a model for a single hydrogen atom.

Question 2

Molecule

Answer 2

2 or more atoms joined in a chemical bond. In nature, only living cells make the molecules of life: complex carbohydrates and lipids, proteins, DNA, and RNA.

Question 3

Cell

Answer 3

Smallest unit that can live and reproduce on its own or as a part of a multi celled organism. A cell has DNA, an outermost membrane, and other components.

Question 4

Tissue

Answer 4

Organized array of cells and substances that are interacting in some task. Bone tissue consists of secretions from cells.

Question 5

Organ

Answer 5

Structural unit of two or more tissues that interact in one or more tasks.

Question 6

Organ System

Answer 6

Organs that interact in one or more tasks.

Question 7

Multi-Celled Organism

Answer 7

Individual made of different types of cells. Cells of most multi celled organisms make up tissues, organs, and organ systems.

Question 8

Population

Answer 8

Group of single-celled or multi-celled individuals of a species in a given area.

Question 9

Community

Answer 9

All populations of all species in a specified area.

Question 10

Ecosystem

Answer 10

A community that is interacting with its physical environment through inputs and outputs of energy and materials.

Question 11

Biosphere

Answer 11

All regions of Earth’s waters, crust, and atmosphere that hold organism. In the vast universe earth is a rare planet. Life as we know it is impossible without its abundant supply of water.