1. Body Systems Overview 1

2. 1. cell membrane - the thin outer covering of a cell; holds the cell together
2. nucleus – the small central core in almost every cell; stores information and directs all the activities of the cell.
3. cytoplasm – the material between the cell membrane and the nucleus; made up of many parts that help the cell work 2

3. 4. cell – is the basic unit of all living things
5. tissue – a group of cells that are alike and work together to do the same job.
6. organ – a body part made up of various tissues; does a certain job in the body.
7. body system – a group of organs that work together to do a certain job. 3

4. 1. What are your cells? a. Everything in your body is made of cells
b. Different cells have different shapes and do different jobs 4

5. c. Almost all have the same 3 parts
i. Cell membrane – thin outer covering that holds the cell together, lets in water and everything else the cell needs, keeps out most things that could harm the cell
ii. Nucleus – small center that stores information and directs all the activities of the cell, “brain”, sends messages
iii. Cytoplasm – material that is between the nucleus and cell membrane. Made up of parts that help the cell work. 5

6. 2. What are your tissues?
a. Tissue – a group of cells, ex: muscles, blood, skin, hair, bone
i. Each does a different job and are specially formed for the work they do - “function”
ii. EX: bone cells are hard and cannot bend, skin cells are flat and thin and fit tightly together at the edges 6

7. 3. What are your organs? a. Tissues work together to make up organs
b. Each organ does a specific job to help you stay alive and healthy
c. EX: heart is an organ that pumps the blood, eyes are organs that help you see 7

8. 4. What are your body systems?
d. some organs are part of more than one system
e. systems work together to make sure that the body maintains homeostasis – is the condition in which the body’s internal conditions are at a stable state 8

9. Body Systems System Major Organ(s)
Skeletal Bones, Cartilage, Ligaments
Muscular Muscles & Tendons
Digestive Stomach, Intestines, Liver
Urinary Kidneys, Bladder
Nervous Brain, Spinal Cord
Circulatory Heart
Respiratory Lungs
Endocrine Glands & Hormones 9

10. How do body systems work together?
Skeletal and Muscular
Circulatory and Digestive
Respiratory and Circulatory
Example...when the kidneys (urinary) start to receive less oxygen, they produce a hormone (endocrine) that the blood (circulatory) carries to the bones (skeletal). There, the hormone stimulates the bone marrow to produce more red blood cells (circulatory). 10

11. Body Systems Worksheets11

12. 12

13. Review What are the three main parts of a cell?
What are the three jobs of a cell membrane?
How do cells, tissues and organs work together in the body?
How can a problem in one body system affect another body system? 13