FOM anki flashcards week 2
What is the polarity of water?
Unequal electron sharing between hydrogen and oxygen leads to a dipole (partially positive H, partially negative O).
What structure does water have?
Water has a bent structure (tetrahedral bonding angle).
What are hydrogen bonds?
Bond between hydrogen (positive) and oxygen (negative) or other electronegative atoms. Essential for water’s properties.
How does the hydrophobic effect work?
Non-polar molecules aggregate in aqueous solutions (e.g., micelles, lipid bilayers).
Define amphipathic molecules.
Molecules with both hydrophilic and hydrophobic regions (e.g., phospholipids in cell membranes).
What is the primary function of cell membranes?
Selective barrier to the external environment, involved in signaling, transport, and recognition.
What is the basic structure of amino acids?
Alpha carbon bonded to amino group (-NH₂), carboxyl group (-COOH), hydrogen, and R group (side chain).
Classify amino acids.
Non-polar (hydrophobic), Polar (hydrophilic), Acidic (negative charge), Basic (positive charge).
How are peptide bonds formed?
Peptide bonds form through dehydration between amino acids, with partial double bond character.
Define protein primary structure.
Linear sequence of amino acids forming a polypeptide chain.
Describe the secondary structure of proteins.
Local folding of polypeptide backbone (alpha helix, beta-sheet, triple helix).
How is tertiary structure stabilized?
By hydrogen bonds, disulfide bridges, ionic interactions, and hydrophobic interactions.
What causes protein denaturation?
Disruption of secondary, tertiary, and quaternary structures due to heat, pH extremes, or chemicals.
Describe the quaternary structure of proteins.
Arrangement of multiple polypeptide subunits into a functional protein (e.g., hemoglobin).
What is the role of enzymes?
Biological catalysts that lower activation energy and increase the rate of biochemical reactions.
Describe Michaelis-Menten kinetics.
Relates reaction rate to substrate concentration, with Km (half-maximal velocity) and Vmax (maximum rate).
What are the types of enzyme inhibition?
Competitive, non-competitive, and uncompetitive inhibition.
What is the pH scale?
Measures H⁺ ion concentration, with pH = -log[H⁺].
What does the Henderson-Hasselbalch equation describe?
Relates pH, pKa, and the ratio of acid to conjugate base concentrations.
Explain the function of buffers.
Resist changes in pH by neutralizing added acids or bases.
What is the isoelectric point?
pH at which an amino acid or protein has no net charge.
How is oxygen transported in the blood?
Oxygen diffuses into blood in the alveoli, and hemoglobin carries it to tissues.
Describe the structure of cell membranes.
A lipid bilayer with proteins and carbohydrates, containing amphipathic lipids.
What is the role of the lymphatic system?
Transport excess fluid (lymph) and foreign bodies to lymph nodes for immune defense.
How do veins and arteries differ?
Arteries carry blood away from the heart, veins carry blood back to the heart.
What is the function of the gastrointestinal system?
Digests and absorbs nutrients, processes them in the liver.
How does the respiratory system oxygenate blood?
Air enters the lungs, where oxygen diffuses into blood and is carried by hemoglobin.
How do lymphatic vessels work?
Absorb excess tissue fluid and return it to the bloodstream as lymph.
What is the function of skeletal muscles?
Muscles contract to produce movement at joints.
What is the difference between fibrous, cartilaginous, and synovial joints?
Fibrous joints are least mobile, cartilaginous are intermediate, and synovial are most mobile.
What are the features of synovial joints?
Include a fibrous capsule, synovial fluid, and articular cartilage; types include hinge, pivot, plane, ball and socket.
What is the role of tendons?
Attach muscles to bones, facilitating movement.
What is a reflex?
An involuntary response to a stimulus, tested in clinical exams.
What is homeostasis?
The maintenance of a constant internal environment within a narrow range for survival.
Describe feedback mechanisms in homeostasis.
Positive feedback amplifies changes (e.g., childbirth), negative feedback opposes changes (e.g., blood glucose regulation).
How do X-rays work?
Use electric current to generate X-rays, which pass through the body; denser tissues absorb more.
What are the strengths of CT scans?
Superior resolution for soft tissues, cross-sectional images.
What are the weaknesses of MRI?
Expensive, time-consuming, and some patients experience claustrophobia.
How does ultrasound work?
Uses sound waves to create 2D images, no ionizing radiation.
Describe T1-weighted MRI imaging.
Tissues appear white with black details.
How do bones develop?
Endochondral ossification turns cartilage into bone, especially in long bones.
What are the types of fractures?
Fractures can be categorized by the type of break (e.g., simple, compound).
Explain the structure of bones.
Composed of periosteum, epiphysis (growth ends), and diaphysis (shaft).
