electrical conduction of the heart
The flow of electrical current causes smooth, coordinated heart contractions; they produce pumping action of the
... [Show More] heart
Depolarization
electrical charges on the surface of the muscle cell change from positive to negative
Repolarization
the heart returns to its resting state, and the positive charge is restored to the surface
Where do the electrical impulses begin?
Electrical impulses begin high in the atria in the sinoatrial node, travel to the atrioventricular node and bundle of His, and then move through the Purkinje fibers to the ventricles
Three types of muscle
skeletal, cardiac, smooth
Skeletal muscle
Voluntary muscle/Striated muscle (characteristic stripes): Movement of the body like waving or walking/ Skeletal muscle is attached to the bones of the skeleton
Smooth muscle
Found within blood vessels and intestines
Cardiac muscle
found only within the heart and is able to create and conduct its own electrical impulses
Ligaments
Connect bone to bone
Tendons
Ropelike structures that connect muscles to bones
Cartilage
Smooth connective tissue that covers the ends of bones at mobile joints
Anatomy of lower airway: delivers oxygen to alveoli
Trachea (windpipe): conduit for air entry into the lungs; divides at the carina into two main stem bronchi, right and left
Bronchioles: dilate and constrict as oxygen passes through them
Small bronchioles connect to alveoli: site of oxygen and carbon dioxide exchange
Thyroid cartilage (adam's apple): forms the anterior part of the larynx
Cricoid cartilage: immediately below the thyroid
Cricothyroid membrane
Anatomy of upper airway
Nose, Mouth (Oral Cavity), Jaw (mandible), Tongue, Pharynx, and Larynx (Voice Box)
The Larynx
Does not tolerate any foreign or liquid material and any contact will result in a violent episode of coughing
The nose and mouth lead to the?
Oropharynx (throat)
The pharynx is composed of the?
nasopharynx, oropharynx, laryngopharynx
The nostrils lead to the?
Nasopharynx (above the roof of the mouth and soft palate)
The mouth leads to the?
oropharynx
Two passages that are located at the bottom of the pharynx are?
the trachea (windpipe) and the esophagus (carries food to the digestive system)
The two lungs are held in place by
trachea, arteries and veins, pulmonary ligaments
Right lung's lobes
The right lung has upper, middle, and lower lobes [Show Less]