1. The Human Body
Introduction

2. Movement
The skeleton, muscles, cartilage, tendons, ligaments, joints, and other connective tissues are all part of the musculoskeletal system,
The bones of the skeletal system protect the body’s internal organs and support the weight of the body.
The muscles assist with movement by contracting and pulling on the bones.

3. JOINTS
To allow motion, different bones are connected by joints which are connected to other bones and muscle fibers via connective tissues such as tendons and ligaments.
Cartilage prevents the bone ends from rubbing directly on each other.

4. NERVOUS SYSTEM
The nervous system controls when and how your muscles act on bones
The central nervous system consists of the brain, which controls body functions.
And, the spinal cord, which transmits signals from the brain to the rest of the body.
Cerebrospinal fluid surrounds the brain, cushioning it and providing shock absorption to prevent damage.
The peripheral nervous system - nerves that start within the brain and spinal cord.
It gives information to all parts of the body.

5. Material Transportation
The heart circulates the blood throughout the body.
The circulatory system evolved because simple diffusion was unable to supply all of the cells with nutrients.
The coordination of the circulatory system and the respiratory system to ensure proper gas exchange is very important in animals that have lungs and gills.

6. DIGESTIVE SYSTEMS
Humans obtain lipids, proteins, carbohydrates, essential vitamins, and minerals from the food they consume.
Organs of the digestive system include the mouth, esophagus, stomach, small intestine, and the large intestine.
Organs, such as the liver and pancreas, secrete digestive juices into the gastrointestinal tract to assist with food breakdown.

7. Body Functions
Nervous system and endocrine system work together to control body functions.
Hormones serve as chemical messengers in the body and help maintain homeostasis.
Hormones also play a role in the regulation of cell death, the immune system, reproductive development, mood swings, and hunger cravings.

8. THE ENDOCRINE SYSTEM
The endocrine system, includes the pituitary glands which are responsible for the release of hormones which regulate bodily functions.

9. Your ears, eyes, skin, nose taste buds give information about the environment to the nervous system.
Stimulus and response

10. Homeostasis
Homeostasis: the ability of a system or living organism to adjust its internal environment to maintain a stable equilibrium
Homeostasis is the body’s constant and balanced internal environment.
It requires persistent monitoring and adjustments as conditions change.

11. Positive and Negative Feedback
A positive feedback loop causes a self-amplifying cycle where a physiological change leads to even greater change in the same direction.
A negative feedback loop is a process in which the body senses a change, and activates mechanisms to reverse that change.