science 1st grading

Oxygen - Integral component of atmosphere.

Essential element to support life.

Plays a vital role in carrying out metabolic functions, without metabolism, our body would deteriorate.

As we utilize energy, our demand for oxygen increases.

Metabolic Functions/Metabolism - Produces Carbon Dioxide.

Breathing - Act of drawing air into (inhalation) and eliminating air out (exhalation).

Carbon Dioxide - By-product of energy production in cells, released during exhalation.

Respiratory System - Functions as passage-way of gas into and out of the body.

Allows for filtration, humidification, and warming of air.

Nose, Pharynx, Larynx, Trachea, Bronchi, Lungs.

UPPER RESPIRATORY TRACT:

Nose - Primary organ for smell.

Main entrance for airflow in the body.

Exit point of carbon dioxide.

Nasal Cavity.

Pharynx - Throat

Pathway for air and food.

Air from the nasal cavity enters the nasopharynx (junction between nasal cavity and pharyngeal cavity), and travels down through the oropharynx and the laryngopharynx to enter the larynx.

Food heads toward the esophagus.

Tonsils - Specific tissues categorized into pharyngeal, palatine, and lingual.

Pharyngeal Tonsils - Roof of nasopharynx

Adenoid.

Palatine Tonsils - Located in the oropharynx at the end portion of the soft palate.

Lingual Tonsils - Situated at the base of the tongue.

Larynx - Voice box.

Leads air into the appropriate channel.

Made up of 8 hyaline cartilages and a spoon-shaped elastic cartilage called the epiglottis.

Thyroid Cartilage - Adam’s apple.

Biggest of the hyaline cartilages.

Epiglottis - Protective barrier for lungs.

Prevents food from reaching the lower respiratory tract.

Forms covering for glottis (opening to the larynx and trachea).

LOWER RESPIRATORY TRACT:

Trachea - Also known as windpipe.

Adjoins the esophagus enabling it to extend anteriorly when we swallow.

Consists of ciliated mucosa.

Bronchi - Main passageways of air into the lungs.

Left and right bronchi are formed by division of trachea.

Lungs - Main organs of the respiratory system.

Referred to as respiratory zones (bronchioles, alveolar sacs, and alveoli.)

Left Lung - Has 2 lobes (upper and lower).

Right Lung - Has 3 lobes (upper, middle, and lower)

Pulmonary Ventilation - Air moves in and out of the lungs

Breathing

External Respiration - Carbon dioxide is expelled from lungs.

Internal Respiration - Exchange of gasses.

CIRCULATORY SYSTEM:

Heart - Pumps blood through contractions of cardiac muscles.

Responsible for carrying and distributing nutrients, gasses, hormones, antibodies, and other important substances.

Size of a closed fist.

Has 4 chambers: Right Atrium, Right Ventricle, Left Atrium, Left Ventricle.

Has 4 valves:

1. And 2. Atrioventricular (AV) Valves - Named based on the number of flaps or cusps they have.

Tricuspid Valves - Between right atrium and right ventricle.

Bicuspid Valves - Between left atrium and left ventricle.

3. Pulmonary Valve - Takes blood to lungs.

Between the right ventricle and pulmonary artery.

4. Aortic Valve - Prevents blood from prematurely entering the aorta.

Between the left ventricle and aorta.

Semilunar Valves - Pulmonary and Aortic Valves.

Blood Vessels - Arteries, Veins, Capillaries.

Arteries - Carry blood away from the heart and transport oxygen-rich blood.

Arterioles - Smaller vessels.

Capillaries - Tiniest blood vessels.

Connect arteries and veins.

Merge into venules.

Veins - Carry blood to heart.

Transport oxygen-poor, carbon dioxide-rich blood.

Blood - Fluid that transports oxygen and nourishment to the body cells and aids in excretion of carbon dioxide and waste products from the body.

Maintains body temp and pH.

RBC, WBC, platelets, and plasma.

Red Blood Cells (RBC) - Erythrocytes.

One drop of blood is equal to 5 million RBC.

1 RBC has an average lifespan of 120 days.

Contains hemoglobin, an iron-rich protein.

White Blood Cells (WBC) - Leukocytes.

Battle infection by attacking and destroying germs or foreign particles that enter the body.

Produces more WBC to fight the infection.

Normal body has 7000 WBC per cubic mm of blood. A WBC count higher or lower means a weak immune system.

Should NOT exceed RBC count.

Neutrophils - Most abundant of WBC.

Lymphocytes - Natural killer cells, B cells, and T cells.

Monocytes - Develop into macrophages that can move out of the blood vessels into the site of infection.

Eosinophils - Defend the body against parasitic infections.

Basophils - Function during allergic and antigen reactions.

Platelets - Thrombocytes.

Assists blood clotting process called “coagulation” and prevents excessive bleeding.

Normal platelet count is 150,000 - 450,000 per mm of blood.

Plasma - Pale yellow fluid where the blood cells are suspended.

55% of total blood volume.

Contains wastes because it is the main medium for elimination of waste products from the body cells.