HUMAN BODY SYSTEMS

THE HUMAN BODY

• Anatomy- the study of the structure of living organisms. • Ex: studying the

structure of the heart.

• Physiology-

the study of how

the body works. • Ex: how the heart

works to pump blood, etc.

CELL SPECIALIZATION

• Embryonic Stem Cells- formed during the first few

divisions of the zygote. Have the potential to

become any type of cell in the body.

• Cell Determination- stem cells become committed

to develop into only one type of cell.

• Following this, these cells are considered to be adult stem

cells.

• Cell Differentiation- cells acquire the structures and

functions of highly specialized cells.

APOPTOSIS

• Apoptosis-

programmed

cell death

• ie: webbing

between human fingers-

may also be

used to rid the

body of cells that aren’t

functioning

properly.

LEVELS OF ORGANIZATION

• Cells- basic unit of structure and function.

• Tissues- groups of similar cells working together to

perform a specialized function.

• Organs- different types of tissues that function

together.

• Organ Systems- two or more organs working in a

coordinated way.

• Organism- all of the systems interacting and working

together.

4 TYPES OF TISSUES

• Epithelial- protective sheets of tightly packed cells connected by special junctions. • Ex: skin, membranes of stomach, lungs, nose, etc.

• Connective- supports and binds together and protects organs and tissues. • Ex: tendons, bones, ligaments, and cartilage.

• Muscle- contracts to produce movement. • Includes smooth (involuntary) and skeletal (voluntary) muscles.

• Nervous- transmits and receives information in response to stimuli. Processes information and regulates the body’s response to the environment.

MAJOR BODY SYSTEMS

There are 11 major body systems:

Lymphatic/Immune, Respiratory, Digestive,

Urinary/Excretory, Reproductive (male and female),

Integumentary, Muscular, Skeletal, Nervous, Endocrine, and

Circulatory.

ANATOMICAL TERMS

• Proper Anatomical Position

• The body is upright

• Feet are slightly apart

• Palms facing forward, with thumbs pointed out

• Right and left refer to the right and left side of the cadaver-

not your right and left.

• Skeletal Terms

• Axial Skeleton - includes the head, neck and trunk.

• Appendicular Skeleton- includes the arms and legs

(appendages)

ANATOMICAL TERMS

• Proximal/Distal

• Proximal- closer to the point of origin (trunk)

• Distal- further away from point of origin (trunk)

• Superficial/Deep

• Superficial- on the exterior

• Deep- on the inside

BODY PLANES

• Sagittal Plane- a vertical plane that divides the body into right and left parts. • Midsagittal (Median) Plane- a sagittal plane that lies exactly

in the midline.

• Parasagittal (Lateral) Plane- a sagittal planes offset from the midline.

• Frontal (Coronal) Plane- divides the body into anterior and posterior • Anterior- front (ventral)

• Posterior- back (dorsal)

• Transverse (Horizontal) Plane- divides the body into superior and inferior. • Superior- toward the head

• Inferior- toward the feet

BODY PLANES

• k

BODY PLANES

EXIT SLIP

• What organ systems must work together to bring

oxygen to the body’s cells?

• A cell has undergone determination to become an

endocrine gland cell. If it is transplanted to a leg

muscle, what do you think will happen to this cell?

WARM UP EXERCISE

1. Explain the difference between anatomy and

physiology.

2. Give an anatomical reference using the terms

anterior and posterior.

3. Give another anatomical reference using the

terms lateral and medial.

4. Give one final reference using the terms posterior

and inferior.

HOMEOSTASIS AND FEEDBACK

• Homeostasis- the regulation and maintenance of a constant internal environment. • Includes: temperature, fluids, salts, pH, nutrients, and gases.

• Homeostasis is maintained through positive and negative feedback.

• Positive Feedback- the end product of a reaction speeds up/amplifies its own production. • Ex: Growth hormones during puberty, blood clotting milk

production

• Negative Feedback- an accumulation of an end product of a process slows down that process • Ex: Holding your breath, hunger, body temperature, ATP

production

• Most regulation occurs through negative feedback.

REGULATION OF BODY TEMPERATURE

• Thermoregulation- the process of maintaining a

steady body temperature under a variety of

conditions.

• Hypothalamus- a region in the brain that monitors and

regulates body temperature.

DIABETES

• Normal Glucose Control- when glucose levels gets

too high in blood, pancreas releases insulin which

causes cells to uptake glucose and liver stores

glucose as glycogen. When glucose is low,

glucagon is released from liver and broken down

into glucose until blood glucose levels reach a

certain point.

• Type 1- occurs when the body’s immune system

destroys the ability of specialized cells to produce

insulin. (Cells can’t uptake glucose)

• Type 2- when insulin production decreases or when

insulin cannot move glucose into cells.

WARM UP EXERCISE

5. What is the specific location in the brain

responsible for regulating temperature?

6. What does the term homeostasis mean?

7. Name the four main tissue types.

8. Explain the difference in the axial and

appendicular skeleton.

HOW ORGANS COMMUNICATE

• Two major systems allow cells to communicate:

• Nervous System- a network of connected cells tissues and

organs that help control many life processes.

• The nervous system sends messages that runs along a specific

pathway through specialized tissues until they reach their target

cell.

• Works rapidly with short quick response.

• Endocrine System- a collection of organs that help control

growth, development and response to the environment.

• The endocrine system sends a broad message, through the

blood stream in the form of molecules called hormones. Only

cells with receptors for a specific hormones can respond to its

signal.

• Responds more slowly, but the duration of the response is

longer.

HOW ORGANS COMMUNICATE

• Stimulus- anything that causes a response.

• Change can be chemical, cellular, or behavioral.

THE NERVOUS SYSTEM

• The nervous system is divided into 2 major parts:

• Central Nervous System (CNS)- includes the brain

and the spinal cord.

• Interprets messages from other nerves in the body and stores some of the messages for later use.

• Peripheral Nervous System (PNS)- includes nerves

extending from the brain and spinal cord.

• Helps transmit messages between the brain and other organs in the body.

NEURONS

• Neuron- a specialized cell that stores information

and carries messages within the nervous system and

between other body systems.

TYPES OF NEURONS

• There are three main types of neurons

• Sensory Neurons- detect stimuli and transmit signals to the

brain and spinal cord.

• Interneurons- make up the brain and spinal cord. Receive

signals from sensory neurons and process the information to pass the signals on the motor neurons.

• Motor Neurons- pass messages from the nervous system to

other tissues in the body, such as muscles.

RESTING POTENTIAL

• Neurons transmit information in the form of

electrical and chemical impulses.

• When neurons aren’t transmitting a signal, they are

considered to be “at rest.” While at rest, the neuron

maintains a negative charge, called the resting

potential- this is the potential energy needed to

transmit a nerve impulse.

RESTING POTENTIAL

• Two types of ions (Na+/K+) allow for the resting potential. • More Na+ ions are present on

the outside than inside, and fewer K+ ions are present on the outside that inside.

• Sodium-Potassium Pump- protein channel found in the membrane of the neuron- transports Na+ out and brings K+ ion. (active transport) • This helps maintain resting

potential.

EXIT SLIP

• Which system- nervous or endocrine- allows you to

react to slam on your brakes when the someone

stops quickly in front of you?

• How might a clogged blood vessel affect the

nervous system’s and endocrine system’s abilities to

deliver signals?

• How does a neuron’s shape allow it to send signals

across long distances?