First Aid for Bleeding, Injuries, and Emergencies
Otorrhagia: Bleeding from the Ear
Skull fracture may cause this. AUXI 1: Do not put anything in the ear. Side-lying position and carry the patient if bleeding.
Epistaxis: Nosebleed
May be related to hypertension. AUXI 1: Do not put anything in the nose. Apply pressure to the nose for 10 minutes. If clots form, plug with cotton wool with hydrogen peroxide.
Hematemesis: Vomiting Blood
Black blood from the mouth. AUXI 1: Place the patient on their side, take samples, and carry the patient.
Hemoptysis: Coughing
Read MoreUnderstanding Hearing, Touch, and Sensory Receptors
Hearing: How Does it Work?
Sound waves are produced by vibrations of air molecules or any object. When these waves reach the eardrum, it begins to vibrate and transmit the vibrations to the ossicular chain. The greater the intensity of sound, the greater the vibration. The last ossicle (stapes) transfers the vibration to the oval window, in which it rests. This, in turn, causes vibration of the inner ear perilymph, leading to the excitation of certain cells inside the cochlea, called the organ of
Read MoreCell Membrane Models and Transport Mechanisms
Membrane Models
1. Gorter and Grendel (1925): Extracted lipids from erythrocyte membranes. By calculating that spreading them on water resulted in twice the area that should be addressed by erythrocyte membranes, they concluded that the membrane is a bimolecular lipid layer.
2. Danielli and Davson (1935): Proposed a model of the plasma membrane structure in which proteins are located in the polar groups (hydrophilic) of the lipid bilayer. Their model included pores or channels in the membrane to explain
Read MoreUnderstanding the Nervous System and Brain Function
Membrane Potential and Neuronal Function
1. What is a Membrane Potential?
The membrane potential is the electrical charge of the inside of a cell relative to the outside of the cell.
2. What is the membrane potential at these stages?
- a. Rest: -70mV
- b. The end of Depolarization: +30mV
- c. The end of Repolarization: -70mV
- d. Hyperpolarization: More negative than -70mV
3. In a single round of the Sodium-Potassium pump, which elements (and how many) move through the plasma membrane?
3 sodium ions (Na+) move out,
Read MoreHuman Anatomy and Physiology: Key Concepts
Trachea and Cilia Function
What is the purpose of having C-shaped cartilages in the trachea? What about the cilia lining the inside of the tube?
C-shaped tracheal cartilages made of hyaline cartilage maintain the integrity of the airway. The inner lining of ciliated epithelium tissue reinforces the anterior and lateral sides of the trachea to protect and maintain the airway open. The cilia move back and forth to sweep the mucus upwards towards the throat.
Oxygen Transport: Respiratory and Circulatory
Read MoreHuman Placenta: Formation, Structure, and Function
The Placenta: Structure and Function
The placenta is composed of maternal and, especially, fetal tissues. The structure facilitates contact between maternal and fetal blood circulations across the largest possible area, while maintaining their independence, at least until delivery. The human placenta exhibits the following characteristics:
- Hemochorial: The egg implants in the uterine lining, with the trophoblast penetrating the endometrium to erode the endothelium of uterine vessels, establishing