body systems

What are the levels of cell organization in the human body?

Cell —> Tissue —> Organ —> Organ System

What are the 11 organ systems of the body?

• Integumentary
• Skeletal
• Muscular
• Nervous
• Endocrine
• Cardiovascular
• Lymphatic
• Respiratory
• Digestive
• Urinary
• Reproductive

What is the general function of the integumentary system?

To protect the body from fluid loss, injury, and infection

What is the general function of the skeletal system?

To give support, protection, movement and mineral/growth storage

What is the general function of the muscular system?

To move the body internally and externally

What is the general function of the nervous system?

To respond to external stimuli and to help your body maintain homeostasis

What is the general function of the endocrine system?

To maintain homeostasis and produce hormones

What is the general function of the cardiovascular system?

To circulate blood throughout the body to meet the needs of body cells

What is the general function of the lymphatic system?

Part of the immune system, as well as fluid recovery

What is the general function of the respiratory system?

Taking in oxygen and expelling carbon dioxide

What is the general function of the digestive system?

Break down food, absorb nutrients and eliminate waste

What is the general function of the urinary system?

To remove nitrogenous wastes and excess water and salts from the bloodstream

What is the general function of the reproductive system?

To produce offspring

What are the main components of the integumentary system?

skin, nails, hair follicles, and glands

What are the main components of the skeletal system?

bones, joints, ligaments, cartilage

What are the main components of the muscular system?

skeletal/cardiac/smooth muscle and tendons

What are the main components of the nervous system?

brain, spinal cord, nerves

What are the main components of the endocrine system?

pituitary, thyroid, pancreas, adrenal, and other hormone-secreting glands

What are the main components of the cardiovascular system?

heart, blood vessels, blood

What are the main components of the lymphatic system?

lymphatic vessels, lymphatic tissue, lymphoid organs

What are the main components of the respiratory system?

nose, pharynx, larynx, trachea, bronchi, lungs

What are the main components of the digestive system?

mouth, pharynx, esophagus, stomach, intestines, liver, pancreas, anus

What are the main components of the urinary system?

kidneys, ureters, bladder, urethra

What are the main components of the reproductive system?

male and female reproductive structures

What are dendrites?

branchlike extensions of the neuron that detect information(signals) from other neurons

What are soma?

Cell body; like a control center processing the incoming signals

What are axons?

Long fibers sending signals away from the cell body

What are axon terminals?

End of axons; passing signals to the next cell

What are myelin sheaths?

Fatty coverings (made by glial cells) that speed up signal transmission along the axon

What are nodes of ranvier?

Gaps in the myelin sheath where the signal jumps (called a saltatory conduction)

How is action potential generated down a neuron?

Starts at the resting potential, goes through depolarization, repolarization, hyperpolarization, then it goes back to the resting potential

How is action potential transmitted across the synapse?

Action potential reaches the axon terminals and releases neurotransmitters, which then crosses the synapse and binds receptors onto the next neuron's dendrites
(that can either excite or inhibit the next neuron)

What is the path of food in the digestive system?

mouth, esophagus, stomach, small intestine, large intestine, rectum, anus

What involuntary process is food moved through the major organs?

Peristalsis

What enzymes are responsible for digesting the various macromolecules?

Amylase and lipase

What is the importance of villi in the small intestine?

More villi means more surface area, which means higher absorption chances and rates

What are the three types of muscle tissue?

skeletal muscle, smooth muscle, cardiac muscle

What is skeletal muscle?

A type of voluntary muscle, attached to bones by tendons

What is smooth muscle?

A type of involuntary muscle, lines organs

What is cardiac muscle?

A type of involuntary muscle, makes up the thick inner layer of the heart

What are the four types of body tissue?

connective, epithelial, muscle, nervous

What is connective tissue?

It supports and binds, like tendons and ligaments

What is epithelial tissue?

A protective surrounding/lining, like skin

What is muscle tissue?

Responsible for both voluntary and involuntary movement

What is nervous tissue?

Neurons and the cells that support them

How does a muscle contract?

The sliding filament theory

What is the sliding filament theory?

It explains how muscles contract by describing the sliding of actin and myosin filaments past each other; sarcomeres contain overlapping actin(thin) and myosin(thick) filaments- the power stroke myosin heads attach to actin and pulls the actin filament towards the center of the cell, shortening the sarcomere

What are the two divisions of the skeletal system?

Axial and appendicular

What are examples of axial bones?

Skull, sternum, ribs, vertebrae

What are some examples of appendicular bones?

Everything besides axial bones (skull, sternum, ribs, vertebrae)

What connective tissue holds bones together?

Ligaments

What connective tissue holds muscle to bones?

Tendons

What are the parts of the heart?

Right and left pulmonary veins, right and left pulmonary arteries, right and left atrium, right and left ventricle, superior and inferior vena cava, and the aorta

How does blood flow through the heart?

Superior and inferior vena cava, right atrium, right ventricle, right and left pulmonary arteries, lungs (to get oxygenated), right and left pulmonary veins, left atrium, left ventricle, aorta, rest of body

How many chambers are in the heart?

4

What direction do arteries move blood?

Away from the heart

What direction do veins move blood?

Back towards the heart

What are the four main components of blood?

Red blood cells (RBCs)
White blood cells (WBCs)
Platelets
Plasma

What are red blood cells?

They carry oxygen and carbon dioxide, made of hemoglobin, made in bone marrow

What are white blood cells?

In the immune system, fight disease, made in bone marrow

What are platelets?

Also known as thrombocytes, small cell fragments that form blood clots

What is plasma?

The liquid portion of blood, mostly made of water, carries dissolved materials

How does breathing work?

Inhalation: diaphragm contracts while the ribcage expands, pulling air into the lungs
Exhalation: diaphragm expands while the ribcage contracts, pushing air out of the lungs

Why are alveoli important in the lungs?

They are the site for gas exchange

Why are there so many bronchioles?

So there is more surface area, which means more alveoli for more gas exchange

What are the types of joints?

Suture (immovable), ball and socket (widest range of motion), pivot (rotation), hinge (like a door hinge), gliding/planar (side to side, back and forth)

What is the prostomium?

The first body segment in an earthworm, in front of the mouth

What is the clitellum?

A raised band encircling the body, made up of reproductive segments

What are setae?

External bristle-like structures, used for movement

What is the cuticle?

A waxy, outer covering, preventing water loss and letting gases diffuse through the skin

How does feeding and digestion work in an earthworm?

Ingesting soil as they move through it, going down the pharynx and esophagus, entering the crop (temporary storage area), moving on to the gizzard where the soil in grinded down and organic matter is broken down and released, going through the intestine and either being digested or eliminated through the anus

How do earthworms reproduce?

Although they are hermaphrodatic, they cannot reproduce asexually, instead fusing their bodies together at the clitellum

How many bones are in the human body?

Over 300 at birth, they then fuse together to form 206 in mature adults

What are the two types of digestion?

Chemical and mechanical

What are the three types of bone marrow?

Yellow, spongy red, and compact