What are the 4 levels of

organization in the body?

A cell is a basic unit of structure and

function in living things. Individual

cells in a multicellular organism

tend to be specialized.

A tissue is a group of cells

that perform a single function.

What are the 4 major types of

tissues in the human body?

 Epithelial

Connective

Nervous

muscle

Movements of the body are

possible because of muscle tissues.

Examples: Skeletal muscles, muscles

surrounding the digestive tract,

blood vessels and the heart

A group of different types of tissues

that work together to perform a single

function or several related

functions is called what?

An organ system is a group of

organs that perform closely related

functions. The organ systems interact

to maintain homeostasis

in the body as a whole. 

Example: the brain and spinal cord

are organs of the nervous system.

Homeostasis describes the relatively

constant internal conditions that organisms

maintain despite changes in the

internal and external environments.

Feedback inhibition, or negative feedback,

is the process in which a stimulus

produces a response that

opposes the original stimulus.

Compare homeostasis to a

furnace in your home.

In a home, heat is supplied by a furnace.

When the temp drops below a

set point, a thermostat sensor

switches the furnace on thus

heating the house. When the

temperature reaches the set point,

the furnace kicks off. This is a

nonliving example of how homeostasis works

Give an example of how a biological

system maintains homeostasis?

A good example is how the body regulates temperature.

A part of the brain called a hypothalamus contains

nerve cells that monitor body temperature.

If the nerve cells sense that the core

temp has dropped much below 37 degrees

Celsius, the hypothalamus produces

chemicals that signal cells through the

body to speed up activities. Heat produced by

the activities, especially because of cellular

respiration, causes a rise in body temperature.

It is part of the digestive system

because it produces bile, however,

the liver is one of the body’s most

important organs for homeostasis.

What is one of the liver’s

most important roles?

Its VIP role involves regulating the level

of a substance we take almost for

granted–glucose. Glucose comes from

the food we eat, and cells take glucose

from the blood to serve as a source of

energy. After eating, glucose rises.

Then–the liver kicks in and takes

glucose out of the blood and keeps

glucose levels from rising too much.

What are the 7 body systems

that we studied for this unit?

 Digestive system

Muscular system

Circulatory system

Skeletal system

Respiratory system

Immune system

Endocrine system

This system converts food into

small molecules that can be used by the what?

**Ingestion

**Mechanical (chewing) and chemical

digestion (enzymes break down food molecules)

**Absorption from the small intestine

elimination

The lining of the small intestine consists

of folds that are covered with tiny

projections called villi. Within each

villus there is a network of blood

capillaries and lymph vessels

that absorb and carry away nutrients.

Chyme the pulpy acidic fluid which

passes from the stomach to the

small intestine, consisting of gastric

juices and partly digested food.

The circulatory system transports oxygen,

nutrients, and other substances throughout

the body and it removes wastes from tissues.

How many chambers are

in the human heart?

What separates the right side of

the heart from the left side?

Describe what the right side of

the heart is responsible for?

The right side of the heart pumps

oxygen-poor blood from the heart

to the lungs through the pulmonary circulation

Describe what the left side of

the heart is responsible for?

The left side of the heart pumps

oxygen-rich blood to the rest of the

body through the systemic circulation.

Blood leaves the heart to go to

the rest of the body through what?

Large vessels, or arteries carry

blood from the heart to the tissues of the body.

Pulmonary circulation carries blood

between the heart and the lungs.

Systemic circulation carries blood

between the heart and the rest of the body.

What are the smallest blood

vessels in the body?

After blood passes through the

capillaries it returns to the

heart through the veins.

Other than serving as the body’s

transportation system, what else

does blood help the body with?

Blood also helps regulate body temperature,

fight infections, and produce clots to

minimize the loss of body fluids from wounds.

Which blood cells are the most

numerous in the body?

They are the “army” of the circulatory

system. These cells guard against

infection, fight parasites, and attack bacteria.

Why do minor cuts and scrapes

bleed for a bit and then stop?

Platelets and plasma proteins

cause blood to clot.

The respiratory system picks up

oxygen from the air as we inhale

and releases carbon dioxide as we exhale.

Describe the air flow of

the respiratory system

Air enters the respiratory system, its warmed

and filtered in the inner nasal cavity

and sinuses. Air moves from the nose

to a cavity at the back of the mouth, called the

pharynx, then into the trachea. Between the

pharynx and trachea is the larynx which

controls your ability to speak. From the

trachea, air moves into 2 large tubes

called bronchi leading to the lungs. The bronchioles

lead to several hundred million tiny air sacs called alveoli. 

Nose→ pharynx → larynx → trachea → bronchi → lungs

What muscle creates a partial vacuum

inside the chest cavity when you inhale?

As air enters the alveoli, oxygen diffuses

across thin capillary walls into the

blood. Meanwhile, carbon dioxide

diffuses in the opposite direction.

True or False? There are

muscles in the lungs.

False. There are no muscles in the

lungs and there are no muscles

connected directly to them

that participate in breathing.

The skeletal system supports the body,

protects internal organs, assists in

movement, stores minerals, and

is a site of blood cell formation.

How many bones are there

in the human body?

There are 2 parts of the

skeleton, what are they?

The axial skeleton and the

appendicular skeleton.

What makes up the

appendicular skeleton?

The bones of the arms, legs, pelvis,

and shoulder area make up

this portion of the skeleton.

Bones are living tissues, made up of

a solid network of cells and

protein fibers surrounded by

deposits of calcium salts.

• Support: give shape to the body

• Protection: protect internal organs 

• Movement: provide a system of levers on which

  muscles produce movement. 

• Mineral Storage: contain reserve minerals, including calcium

• Blood Cell Formation: blood cells produced in soft tissue

  that fills the internal cavities of some bones.

A joint is a place where 2 or more bones

meet each other. They contain connective

tissue that holds bones together

and allows for movement.

Fixed/immovable (skull), slightly movable

(between vertebrae in spine) or

freely movable (shoulder joints).

What are the 4 types of

freely movable joints?

Ball and socket (shoulders and hips) 

Hinge (elbows, knees)

Saddle (thumb to move across a palm)

Pivot (shake head to say no)

There are 3 different types of muscle

tissues that are specialized for different

functions: skeletal, smooth,

and cardiac muscle.

They are attached to bones. Responsible

for voluntary movement

Smooth muscles are found throughout

the body to form walls of hollow structures,

like the stomach, intestines and blood vessels.

They are found in just 1 place

in the body–the heart!

A muscle produces force by contracting

in one direction. We use muscles to

push as well as pull because muscles

work in opposing pairs around joints.

When one muscle pair contracts the

other muscle in the pair relaxes.

The endocrine system helps regulate

mood and metabolism, tissue function,

growth and development, and reproductive

processes. This system produces chemicals

called hormones that affect many parts

of the body. The glands of the endocrine

system release hormones that travel

through the blood and control the

actions of cells, tissues and organs.

Thought negative feedback aka feedback

inhibition…this occurs when an

increase in a substance “feeds

back” in a way that inhibits the system.

What are 2 ways that the endocrine

system maintains homeostasis?

1. Maintaining water balance 

2. Regulating blood glucose

Infectious disease occurs when

microorganisms disrupt normal

body functions. Infectious diseases

are caused by fungi, bacteria,

viruses, “protists” and other pathogens.

Pathogens are the microorganisms

that cause infectious

disease–AKA sickness producers.

What are a few ways that

infectious disease is spread?

Pathogens can be spread through

coughing, sneezing and physical

contact. Some can be spread through

sexual contact. Others can be transferred

by blood transfusions. Pathogens can

infect any part of the body.

Nonspecific defenses include the skin,

tears and other secretions; the

inflammatory response and fever.

The skin. Even the openings of the skin

have secretions that contain lysozyme

which is an enzyme that breaks

down bacterial cell walls.

What is the second line of

defense for the body?

The inflammatory response is a nonspecific

defense reaction to tissue damage

caused by injury and infection.

The immune system specific defenses

distinguish between “self” and “other”,

inactivating or killing foreign

substances or cells.

How does the immune system distinguish

and recognize “self” and

“nonself” in the body?

The immune system recognizes cells

that belong to the body as “self” These

cells carry chemical markers that act

as passwords saying “don’t

attack me, I belong here!”

“Nonself” is a cell that is not recognized

and the immune system goes to work,

using cellular and chemical

weapons to attack it.

True. Once the immune system has encountered

an invader, they remember it, enabling

the immune system to more rapidly

and effectively respond to the pathogen.

Any foreign substance that can

stimulate an immune response is an _________.

Vaccines work by taking advantage

of antigens and immunological memory.

Vaccines contain the antigens of

pathogens that cause disease. When

a person is vaccinated with these

antigens, the immune system

generates antibody-producing cells.

If the body comes in contact with the

antigen again, the immune system

will be ready to fight it.

What are the 2 main working

cells of the immune system?

T Cells

B Cells

Give a few examples of

immune system disorders?

AIDS

Asthma

Allergies

Autoimmune disease

Allergens like rag weed and pollen

trigger inflammatory responses, causing

sneezing, watery eyes, etc. Drugs

called antihistamines help relieve symptoms

What is asthma and how does

it affect the immune system?

Allergic reactions in the respiratory

system can create asthma. Air

passages narrow causing difficulty

breathing. Inhaled medication can

relax smooth muscles around the

airways and relieve the symptoms.

What is an autoimmune disease

and how does it affect the immune system?

Autoimmune diseases is when the body’s

own immune system attacks its own

body’s cells. An example is type 1 diabetes.

If you were to order the levels of

organization from simplest to most

complex in the body, what would it be?

To maintain homeostasis, what is the

correct order in which these events occur?

1. The body absorbs food molecules after eating.

2. The levels of glucose in the blood rises.

3. The liver removes glucose from the blood

4. As the body uses glucose for energy, the liver release stored glucose into the blood.

Why is it important for an

organism to maintain homeostasis?

It is important for organisms to maintain

homeostasis because cells and organs

require certain conditions to function properly

What are the components of blood

and what are their functions?

Blood is made of plasma, red blood cells,

white blood cells and platelets. Plasma

controls body temperature, carries

substances through the body and

fights infection. Red blood cells transport

oxygen. White blood cells fight infection.

Platelets help the blood to clot.

HIV is a human immunodeficiency virus. HIV attacks key cells within the immune system, leaving the body with inadequate protection against pathogens. HIV is a retrovirus that carries its genetic info in RNA rather than DNA. Over time HIV destroys T Cells crippling the ability of the immune system to fight HIV itself and other pathogens, which leads to AIDS. 

HIV is transmitted in 4 ways: sex, sharing needles, contact with blood, transmission from infected mom to child.