Human biology final

What are the two main zones of the respiratory system

Conducting zone and respiratory zone

What is the function of the conducting zone?

Moves air in and out; filters, warms, and moistens air

What organs are in the conducting zone?

Nose, nasal cavity, sinuses, pharynx, larynx, trachea, bronchi → terminal bronchioles

What us the function of the respiratory zone?

Gas exchange

What structures are included?

Lungs and alveoli

What is the parietal pleura?

Lines the thoracic cavity

What is the visceral pleura?

Covers the lungs

What is pleural fluid?

Lubricates and reduces friction

Respiration steps: What is pulmonary ventilation?

Breathing (air in and out)

What is external Respiration?

Gas exchange between lungs and blood

Respiration: What is transport?

Movement of gases in blood

What is internal Respiration?

Gas exchange between blood and tissues

Control of Respiration: What detects oxygen levels?

Peripheral chemoreceptors (aortic & carotid bodies)

Control of Respiration: When does O2 trigger increased breathing?

When PO2 drops to ~ 60 mm Hg

Breathing Terms: What is hyperventilation?

Excessive breathing → low CO2 (hypocapnia)

What is Apnea?

Temporary cessation of breathing

Disorders: What is Hypoxia?

Inadaquate oxygen to tissues

Causes of Hypoxia?

Low RBCs, low Hb, blocked circulation, poisons, lung disease, CO

What happens in Asthma?

Inflammation, mucus, bronchospasm

Cause of Tuberculosis?

Mycobacterium tuberculosis

Main cause of lung cancer

Smoking (~90%)

Development? How does a fetus get oxygen?

Placenta

When can premature babies breathe?

~28 week

What happens at birth

Lungs inflate, breathing begins

Processes: What is ingestion

Taking in food

Mechanical digestion examples?

Chewing, churning, segmentation

Chemical digestion occurs when?

Mostly small intestine

What is peristalsis?

Wave-like movement of food

Functions of the tongue?

Moves food, forms bolus, swallowing, taste, speech

Stomach: What does gastric juice contain?

Pepsin, HCL, intrinsic factors, lipase

Stomach: Why is intrinsic factor important

Absorbs vitamin B12

Stomach: Can gastrectomy cause anemia

Yes (B12)

Small Intestine: Main function

Digestion & Absorption

Small intestine: Length and Range?

~2-4 m; from stomach to large intestine

Digestive function of liver?

Produce bile (fat emulsification)

Gallbladder function

Stores bile

What does Pancreas secrete?

Enzymes + alkaline fluid (pH ~ 8)

Large intestine: Main function?

Absorb water & eliminate feces

Large Intestine: Regions

Cecum, colon, rectum, anal canal

Urinary System: What is filtration

Blood forced through membrane

What is Renal threshold?

Level where substance spills into urine

Normal blood glucose

~70-110 mg/dL

RT for glucose?

_{~180 mg/dL}

Kidney Functions?

• Remove waste

• Regulate BP

• Homeostasis

• Hormones

Normal Urine output/day?

1-1.8L

Urine: Normal pH?

~ 6 (range 4.5-8)

Urine: Color due to?

Urochrome

Reproductive: What are Gonads?

Testes & Ovaries

Male System: Path of sperm?

Epididymis → Ductus deferens → Ejaculatory duct → Urethra

Function of Testosterone?

• Spermatogenesis

• Male traits

• Anabolic effects

Disorders: Risk factors for testicular cancer

Cryptorchidism

What is BPH?

Enlarged prostate

What causes erection?

Blood filling erectile tissues (me)

Female System: How many follicles at puberty?

300,000-400,000

How many mature?

~400

Hormones: Estrogen functions?

• Females traits

• Growth

• Bone health

What happens during Menopause?

Estrogen → hot flashes, bone loss, mood changes

Where does fertilization occur?

Fallopian tube

Where does implantation occur?

Uterus (endometrium)

What is IVF?

Fertilization outside body

What is ICSI?

Sperm injected into egg