7 non-respiratory air movements

1. Name and define 7 non-respiratory air movements and explain their mechanism and result. (7 pts. ) 1) Cough is taking a deep breath, glottis is closed, and air is forced against the closure; suddenly the glottis is opened, and a blast of air passes upward. This rapid rush of air removes the substance that triggered the reflex from the lower respiratory tract.

2) Sneeze is triggered by a mild irritation in the lining of the nasal cavity. A sneeze is a result of a depressed uvula closing the oral cavity off from the pharynx and routing air upward through the nasal cavity; sneezes clear upper respiratory passages.

3) Crying is inspiration (inhalation) followed by release of air in a number of short expirations (exhalations); crying is an emotionally induced response of sadness.

4) Laughing is a deep breath released in a series of short expirations; laughing is an emotionally induced response of happiness.

5) Hiccups are sudden inspirations resulting from spasmodic contractions of the diaphragm while glottis is closed. A hiccup is believed to be initiated by irritation of the phrenic nerves which serve the diaphragm. The hiccup sound occurs when inspired air hits vocal folds of the closed glottis.

6) Yawn is a very deep inspiration, taken with the jaws wide open that ventilates all alveoli. A yawn was believed to be triggered by a need to increase the amount of oxygen in blood, but this theory is questionable.

7) Speech is when air is forced through the larynx, causing vocal cords to vibrate; actions of lips, tongue, and soft palate form words to communicate speech. 2. Name the 8 principal organs of the respiratory system and give their description, features, and function. (10 pts. )

1) Nose is the jutting external portion of the respiratory tract supported by a nasal septum of bone and cartilage.

The internal nasal cavity (hollow space behind nose) is divided by the midline nasal septum and lined with mucosa of ciliated pseudostratified columnar epithelium with goblet cells which secretes mucous. The nose produces mucous which warms and moistens incoming air and traps dust. The tiny hairs called cilia filters out dust and other particles present in the air and protects the nasal passage and other regions of the respiratory tract. The sense of smell receptors are found in the roof of the nasal cavity containing olfactory epithelium tissue.

2) Pharynx is the air and food passageway, consisting of 3 subdivisions (nasopharynx,

oropharynx, and laryngopharynx), moving air from the nasal cavity to the larynx and food from the oral cavity to the esophagus. The pharynx houses the tonsils or lymphoid tissue masses that protect against the antigens that enter this passageway along with air and food. The pharynx is the resonance chamber for speech.

3) Larynx connects pharynx to trachea, and is the framework of muscles and cartilages bound to elastic connective tissue. The cartilages are the thyroid (Adam’s apple), cricoid, and epiglottic. The laryngeal inlet or glottis opening can be closed by the epiglottis or vocal folds.

The larynx serves as an air passageway that houses the true vocal cords for voice production; the epiglottis prevents food from entering the lower respiratory tract by covering the trachea during swallowing.

4) Trachea (windpipe) is the flexible tube running from the larynx and dividing inferiorly into two primary bronchi. The walls contain C-shaped cartilages that are incomplete posteriorly where connected by trachealis muscle. The trachea filters, warms, and moistens the incoming air we inhale.

5) Bronchial tree, or the right and left primary bronchi, subdivides within the lungs to form secondary and tertiary bronchi and bronchioles. The bronchi are air tubes that connect the trachea with the alveoli and carry filtered atmospheric air directly into the lungs. The bronchiolar walls contain a complete layer of smooth muscle. The sympathetic NS and adrenal gland release epinephrine that relaxes smooth muscle and dilates airways. Asthma or allergic reactions constrict distal bronchiole smooth muscle which impedes expiration.

6) Alveoli are microscopic chambers at the terminals of the bronchial tree (bronchioles) consisting of thin-walled layers of simple squamous epithelium intimately associated with pulmonary capillaries for gas exchange. The alveolus is the tiny sac like structure present in the lungs containing Type I alveolar cells where the gaseous exchange takes place between carbon dioxide and oxygen.

Type II alveolar cells or septal cells secrete alveolar fluid containing surfactant which acts as a mixing detergent for efficient gas exchange through diffusion with red blood cells. Surfactant coats the gas exposed surfaces and reduces surface tension of the alveolar fluid. The alveolar dust cells contain wandering macrophages that remove debris from surrounding areas.

7) Lungs are the main organ of the respiratory system composed primarily of alveoli and respiratory passageways located within the pleural cavities of the thorax. The visceral pleura or serous membrane attached to the surface of the lungs produces lubricating fluid. The parietal pleura are attached to the inner surface of the thoracic cavity and the superior surface of the diaphragm compartmentalizing the lungs. The lungs are the site in the body where oxygen is taken into and carbon dioxide is expelled out. The red blood cells present in the blood pick up the oxygen in the lungs and carry and distribute the oxygen to all body cells. The stroma or elastic tissue of the lung allows for passive expiration giving the lung recoil, so it can expel air.

8) Diaphragm is a dome-shaped muscle located at the bottom of the lungs where breathing begins. When we breathe in the diaphragm contracts, flatten out and pull downward. Due to this movement the space in the lungs increases and pulls air into the lungs to equalize pressure. When we breathe out, the diaphragm relaxes and moves back up, reducing the amount of space in the lungs which pushes air out. 3. A. Name the 4 features common to chronic obstructive pulmonary disease (COPD). (4 pts.) B. What are two of the most prevalent COPD’s summarizing them briefly? (2 pts. ) A. The four features common to COPD are: 1) Patients almost always have a history of smoking. 2) Dyspnea (shortness of breath) or labored breathing often referred to as “air hunger,” occurs and gets progressively more severe. 3) Coughing and frequent pulmonary infections are common. 4) Most COPD victims develop respiratory failure accompanied by hypoxemia (oxygen deficiency), carbon dioxide retention, and respiratory acidosis. B. Obstructive emphysema (destruction and enlargement of the alveoli) and chronic bronchitis (increased mucus and bronchial swelling from inflamed mucosa) are the most common conditions that make up COPD. 4. Name and describe the main structures of the urinary system. (5 pts. )

The kidneys produce urine. The urine-producing units in the kidney are nephrons which are responsible for the removal of the waste product of urea from the blood; and the filtration and regulated reabsorption of sodium and water. The ureters are a pair of muscular tubes that start at the renal pelvis and extend to the urinary bladder. Every 30 seconds a wave of contractions begin and travel through the ureters taking urine from the renal pelvis into the urinary bladder.

The urinary bladder is an expandable muscular sac that stores urine up to a liter, and is surrounded by the opening of the ureter and the entrance of the urethra, where the internal sphincter provides involuntary control over the discharge of urine. When empty, the bladder muscle wall becomes thicker and the entire bladder becomes firm. As the ureters fill the bladder, the detrusor muscle wall thins and the bladder moves upward, toward the abdominal cavity. The trigone helps prevent stretching of the urethra or backflow of urine into the ureters (squeezes their ends and closes the vesicoureteral orifice).

The urethra extends to the tip of the penis and carries sperm and urine in males. In females the urethra is very short and transports urine only. 5. Name and describe the role of each segment of the nephron and vasa recta. (8 pts. ) The renal corpuscle includes the Bowman’s or Glomerular Capsule, a capsule-shaped membranous structure surrounding the glomerulus of each nephron in the kidneys that extracts wastes, excess salts, and water from the blood. The Glomerular Capsule forms a chamber containing the glomerulus and the glomerular capillary knot which produces a glomerular filtrate or capsular urine.

Blood enters the glomerular capillaries which are specialized for filtration and removal of wastes via the afferent arterioles into the glomerulus and out the efferent arteriole. The reabsorption of water, uric acid, ionic compounds (sodium, potassium, chloride), organic nutrients (glucose, creatine, amino acids), and secretion of histamine, creatinine, and hydrogen ions occurs at the proximal convoluted tubule. The nephron loop of Henle or descending limb reabsorbs water, while the ascending limb of nephron loop reabsorbs more water, sodium, potassium, and chloride ions into surrounding interstitial fluid and capillaries.

Even after filtration has occurred, the distal convoluted tubules continue to secrete additional substances into the tubular fluid such as toxins (ammonia/urea), acids (hydrogen ions), and reabsorb more water and sodium. The vasa recta or peritubular capillaries are blood capillaries which collects the filtered blood from the efferent arteriole. The useful molecules (salts and water) are reabsorbed from renal tubule into the blood in the vasa recta. The vasa recta conveys this blood to the renal venules and then these venules unite together to form the renal vein. (The renal veins are veins that drain the kidney.

They carry the blood filtered by the kidney to the inferior vena cava. )  The collecting duct controls final regulated variable reabsorption of fluid (water), in which hormones (ADH) control the rate of transport of sodium and water depending on systemic conditions. The final product of these processes of glomerular filtration, renal tubular reabsorption and secretion and reabsorption by the collecting duct is a urine concentration that is transported to the minor calyx by a central papillary duct. 6. A) Define renal failure. (1 pt. )  B)  Give 5 possible causes of renal failure. (5 pts. )

A)  Renal failure occurs when the kidneys are unable to concentrate urine, so nitrogenous waste accumulates in the blood, and acid-base and electrolyte imbalances occur severely damaging the nephrons. Damaged nephrons can’t filter wastes from the blood, and the few undamaged nephrons present cannot carry out normal kidney functions. B)  Five possible causes of renal failure are: 1) Repeated damaging infections of the kidney called pyelonephritis an  inflammation of the kidney due to a bacterial infection. 2) Physical injury to the kidneys (a lesion) or a major physical trauma to the kidney (kidney punch).

3) Prolonged pressure on skeletal muscles causing the release of myoglobin (iron- and oxygen-binding protein of muscle becomes viscous) that can clog the renal tubules. 4) Chemical poisoning of the tubule cells by heavy metals (lead or mercury) or organic solvents such as dry-cleaning fluid, paint thinner, acetone, and other toxic removal products. 5)  Inadequate blood supply to the tubule cells as may happen with arteriosclerosis, hardening of the artery walls occurring in old age. 7. Name the organs and give the function of the male reproductive system. (8 pts. )

Penis:  The penis is the male organ used in sexual intercourse it also conveys urine and semen to the outside of the body through the urethra at the tip. The glans of the penis contains a number of sensitive nerve endings associated with feelings of pleasure during sexual intercourse. As the penis fills with blood, it becomes rigid and erect, which allows for penetration during sexual intercourse. Semen, which contains sperm (reproductive cells) is ejaculated through the end of the penis when the man reaches an orgasm. When the penis is erect, the flow of urine is blocked from the urethra, allowing only semen to be ejaculated at orgasm.

Scrotum: The scrotum is the loose pouch-like sac of skin that hangs behind and below the penis containing many nerves and blood vessels. The scrotum primarily contains the testicles (also called testes) which are divided into two chambers by the medial septum. The scrotum acts as a “climate control system” for the testes. For normal sperm development, the testes must be at a temperature slightly cooler than body temperature. Special dartos muscles in the wall of the scrotum allow it to contract and relax, moving the testicles closer to the body for warmth or farther away from the body to cool the temperature.

Testicles (testes): The testicles are oval organs about the size of large olives that lie in the scrotum, secured at either end by a structure called the spermatic cord. The interstitial cells of the testes are responsible for making and secreting testosterone, the primary male sex hormone. Within the testes are coiled masses of tubes called seminiferous tubules that are responsible for producing sperm cells. 8. Name the organs and give the function of the female reproductive system. (5 pts. )

Ovaries: The ovaries are small, oval-shaped glands that are located on both sides of the uterus producing oocytes (eggs/ovum), and the female sex hormones of estrogen (more FSH and LH cause the ovary to produce more estrogen. The ensuing LH surge is responsible for ovulation) and progesterone (necessary for implantation of the fertilized egg in the uterus and for maintaining pregnancy). Fallopian or uterine tubes: Fallopian tubes are narrow tubes that are attached to the upper part of the uterus and serve as tunnels for the ova (egg cells) to travel from the ovaries to the uterus.

Conception, the fertilization of an egg by a sperm, normally occurs in the fallopian tubes. The fertilized egg then moves to the uterus, where it implants into the lining of the uterine wall. Uterus (womb): The uterus is a hollow, pear-shaped organ that is the home to sustaining an embryo, and developing a fetus. The uterus is divided into two parts: the cervix, which is the lower part that opens into the vagina, and the main body of the uterus, called the corpus. The corpus can easily expand to hold a developing baby.

A channel through the cervix allows sperm to enter and menstrual blood to exit. Vagina: The vagina or birth canal is a canal that joins the cervix (the lower part of uterus) to the outside of the body. The vagina conveys uterine secretions to the outside of the body and receives the erect penis during sexual intercourse. The Bartholin’s or vestibular glands are located besides the vaginal opening and produce a fluid (mucus) secretion that moistens and lubricates the vestibule. The vestibule is the space between the labia minora that contains the vaginal and urethral openings.