Cellular Energy & Protein Synthesis

Cell Structure and Energy Production

• Mitochondria are the powerhouse of the cell and contain maternal DNA.
• Oxidative phosphorylation is oxygen-dependent ATP production that is important for cell differentiation, growth, reproduction, thermogenesis, and muscular contraction, producing 95% of ATP and 20x more ATP.
• Anaerobic metabolism is less efficient, produces ATP without oxygen, negatively impacts on homeostasis, and produces lactic acid as a waste product.

Protein Synthesis

• Begins in the nucleolus.
• Genes provide genetic information vital for building a protein.
• Gene expression transforms coded information in a gene into a final product, which dictates the structure and function of a cell by determining which protein is made. It determines the function/purpose of the cell.

Protein Synthesis Process

• Transcription involves DNA being converted into an RNA code, which produces mRNA that carries a copy of the genetic code for a single gene out of the nucleus and into the cytoplasm.
• Translation involves mRNA attaching to a ribosome on the rough ER, where tRNA brings amino acids to the ribosomes to build a protein, and then the mRNA detaches once the protein is built.
• Transportation involves the protein being secreted into a transport molecule, traveling to the golgi apparatus for modification as needed, and then the golgi apparatus releases the protein into a secretory vessel for transportation to the cell surface to be released.

Mutations Impacting Protein Synthesis

• DNA level mutations to genes cause proteins to be shaped incorrectly or to be completely missing.
• tRNA level mutations cause proteins to be built incorrectly at the ribosome level.
• Mitochondrial-linked diseases are mutations in the formation of mitochondria that cause cellular dysfunction.
• Inherited genetic mutations cause diseases such as cystic fibrosis and Huntington's disease.
• Acquired mutations cause diseases such as HIV and cancers due to sun exposure and smoking.

Cellular Waste Removal

• Peroxisomes detoxify molecules and contain catalase and oxidases, and free radicals, especially hydrogen peroxide, inside them.
• Lysosomes digest larger components such as senescent organelles and bacteria, auto-digesting cells after death, starts small and grows by fusing to other vesicles, and contains numerous digestive enzymes and a low pH inside.
• Free radicals are good at certain levels, but if they escape the peroxisome, they can be damaging.

Cellular Transport

• Passive transport involves simple diffusion, where molecules move across the membrane WITHOUT a protein channel, and facilitated diffusion, assisting molecules across the membrane by using protein channel .
• Active transport involves the Na-K ATPase Pump, which requires energy to push more K in and push more Na+ out where Inside cell = ↓ Na+, ↑K, Outside cell = ↑ Na+, ↓ K Endocytosis involves the membrane opening up and engulfing the substance, and pinocytosis, a type of endocytosis, engulfs fluids. Exocytosis involves the release of contents.

Cellular Adaptation

• Atrophy: Cells shrink in size.
• Hypertrophy: Cells grow in size.
• Hyperplasia: Increase in the number of cells.
• Metaplasia: Change in cell morphology.
• Dysplasia: Pathological change leading to disease state that is irreversible.

Cellular Injury

• Hypoxia: cells are deprived of oxygen
• Ischemia: insufficient blood flow
• Chemical agents (drugs, alcohol) and physical agents (trauma, heat) can cause cellular injury Infections
• Psychological stressors or trauma
• Genetic and nutritional defects. Aging

Biochemical Response to Cellular Injury and Free Radicals

• ROS/free radicals are chemically unstable and readily react with other molecules, turning those molecules into free radicals leading to the damage of cell components
• Injury can be created by ionizing radiation, redox reactions, and metabolism of exogenous substances
• Bodies use enzymes to neutralize free radicals
• If not then free radicals can cause cell injury
• Lipid peroxidation leading to membrane damage
• Protein modifications cause increased degradation or loss of activity
• DNA fragmentation leads to mutations

Necrosis vs. Apoptosis

• Necrosis: cells swell up and burst, disorderly breakdown, no energy required, adjacent inflammation, and is never physiological.
• Apoptosis: cells shrivel up and bleb, orderly fragmentation and digestion, energy is required, no adjacent inflammation, and is usually physiological to turn over cells.

Neoplasia

• Benign localized and non-life threatening, polyps and oma suffix, slow-growing, pushes on other body systems but does not invade.
• Malignant cancerous and can spread to other parts of the body, the cells and/or architecture lack normal differentiation, can grow slow or fast, invades other body systems, and frequently metastasizes.

Fluid Regulation

• Hypernatremia (high sodium in the blood) causes symptoms such as thirst, confusion, neuromuscular excitability, seizures, and coma.
• Hyponatremia (low sodium in the blood) causes symptoms such as headache, confusion, stupor, seizures, and coma.
• Hyperkalemia (high potassium in the blood) causes progressive muscle weakness and cardiac issues.
• Hypokalemia (low potassium in the blood) causes spastic paralysis, fatigue, cramps, cardiac issues, including arrhythmias.
• Hypercalcemia (high calcium in the blood) causes cognition changes, confusion, coma, muscle weakness, and arrhythmias.
• Hypocalcemia (low calcium in the blood) causes irritability, anxiety, paresthesia, and bronchospasms.

Starling's Forces

• Net filtrate gets drained out of the interstitial space by the lymph system.
• Hydrostatic pressure, the pressure of the fluid on the capillary wall, pushes fluid out, causing filtration. Oncotic pressure is pressure generated by larger molecules in solution, pulls fluid in, which causes reabsorption.

Forces

• Common causes of edema: blood clot (increases hydrostatic pressure), heart failure (increases hydrostatic pressure), renal failure (decreases oncotic pressure), inflammation (capillaries become leaky), lymph blockage (filtrate is not being drained out, filtrate accumulates)
• Kidneys sense low blood pressure or dehydration and release renin
• Liver produces angiotensinogen, which combines with renin to form angiotensin I
• Lungs use an enzyme ACE (Angiotensin-Converting Enzyme) to turn angiotensin I into angiotensin II
• Angiotensin II tightens blood vessels to raise blood pressure Also signals the next step
• Aldosterone makes the kidneys hold onto salt and water, increasing blood volume, and raising blood pressure
• ADH increases water reabsorption helps produce more concentrated urine to reduce fluid loss and helps maintain blood volume until more fluids are consumed, regulates intravascular pressure and osmolality (balance of fluids and salts in the blood)
• Inadequate ADH leads to Diabetes Insipidus causing dilute excessive water loss that can lead to hypernatremia (high sodium levels)
• Too much ADH causes Syndrome of Inappropriate ADH Secretion (SIADH); urine is very concentrated, and the body holds onto too much water, which can lead to hyponatremia (low sodium levels)

Acid/Base Balance

• Normal values: pH 7.35-7.45, HCO3 20-24 mEq/L, CO2 35-45 mmHg, Na 135-145 mEq/L, K 4 mEq/L, Cl 100 mEq/L
• Respiratory: pH and CO2 are opposite → ↑pH ↓CO2, ↓pH ↑CO2
• Metabolic: pH and HCO3 are equal → ↑pH ↑HCO3, ↓pH ↓HCO3

Metabolic and Respiratory Conditions:

• Metabolic Acidosis - low pH and low HCO3, normal CO2: caused by Normal Anion Gap (too little bicarb- Chronic diarrhea or Elevated Anion Gap hydrogen production- Lactic or Keto acidosis
• Metabolic Alkalosis - high pH and high HCO3, normal CO2: caused by excessive vomiting, Hyperaldosteronism, and medications like diruetics
• Respiratory Acidosis - low pH and normal HCO3, high CO2: caused by Respiratory Depression/ not effectively breathing, Hypoventilation, Medications, some Drugs, and CNS depression
• Respiratory Alkalosis - high pH and normal HCO3, low CO2: caused by Hyperventilation, Altitude sickness, Panic attacks.

Components of Blood & Plasma and Oxygen Dissociation

• The blood consists of about 45% cells and platelets and 55% plasma
• Plasma: liquid portion of the blood
• 91% H2O
• 7% protein-mostly albumin, globulins and clotting factors
• 2% solutes
• Stem cells can differentiate into different cells and are directed by cytokines and growth factors
• Myeloid cell types are mainly RBC, WBC and Platelets
• Lymphoid cell types are mainly Immune Cells and Plasma

Anemia Classifications:

• Microcytic hypochromic - Results from not enough heme(Small cell with low color)
• WBC
• Hemoglobin
• Hematocrit
• Size/Shape RBC(low) cause Chronic blood loss
• Normocytic normochromic - Results from either low RBC production OR high RBC consumption (Cells and Normal Color)
• WBC
• Hemoglobin(low)
• Hematocrit low
• Size/Shape WBC
• Macrocytic normochromic - Cell is, Normal color
• Hemoglobin
• Hematocrit
• Autosomal recessive disease, HbS
• Severity depends on percentage of Hb
• Causes hypoxemia, low pH, low temperature, and decreased plasma volume Causes bilateral pain, extremity edema, acute chest syndrome, and glomerular disease

Immunity & Clotting

• Vitamin K- makes coagulation factors functional proteins C and S and is in intestinal bacteria
• Clotting can be broken into the following simplified process
• Cell is injured which release Tissue Factor and + 7 to activate cascade
• 8+9 then activate 5 & 10 resulting in thrombin
• Prothrombin is converted into Thrombin and prothrombin activates - Fibrinogen into Fibrin which forms clot

WBCs & Immunity

• Neutrophil: granulocyte, WBC, fighting bacterial infection (2nd line of defense)
• Mast cell: Non WBC,Degranulate (break apart) Releases histamine, pro-inflammatory cytokines, and other chemical messengers (2nd line of defense)
• Histamine: dilates vessels Released by mast cells(Chemical Vasodilation Increases capillary permeability)(2nd line of defense)
• Dendritic cell : professional antigen-presenting cell (APC)Communicates between innate and adaptive immune cells(2nd line of defense)
• Cytokine: Can be pro or antiinflammatory cell Mediators in inflammation(2nd line of defense)
• Plasma Complement: WBC
• Largest WBC and promotes good immune resp
• Made in the bone marrow,mature
• CD8: cytoxic T cells,CD4: helper T cells(2nd line of defense)

Characteristics & Defenses

• Level Barrier
• Defensins, cathelicidins
• Epitherlial immune response
• Immediate defenses Lymphocytes VERY SPECIFIC
• Antigens Memory and protection

Antibody Types

• IgG- vaccine
• IgA- found in restortary and dietary
• IgMSHort exposure time

Bacteria Types

• Gran - Gram (+) and Gram (-)
• Replicates intracellularly
• Causes
• TB, pneumonia, strep, pertussis, bubonic plague
• Molds - person to person OR opportunistic(Ringworm)
• Viruses
• Molds are opportunistic(HIV COVID)
• Protozoa
• Parasites
• An animal or plant that survives on or within a host organism

Progression

• Incubation
• Initial exposure
• Hours to years
• Prodromal
• Human Immunodeficiency Virus - attacks cells that help the body fight infection

Hypersensitivity Reactions and Phases

• Anaphylactic- Mediated by IgE and bee stings
• Made bone marrow and mature bone

Cardiac Terms

• Cardiac Output Equation
• CO=HRxSV
• Preload Ventricular stretch prior to contraction; end of diastole
• Afterload Resistance to ejection of blood from the heart; end of systole

Glomerus and Kidneys

• Main functions of the kidney:
• Maintain a stable internal environment for optimal cell and tissue metabolism
• Balance solute and water transpor
• Excreting metabolic waste products
• Conserving nutrients
• Regulating acids and bases
• Endocrine functions: secreting renin regulation,
• Afferent arteriole: brings blood in
• Juxtaglomerular cells produce renin

Nephron & ADH

• Nephron - filters blood to form urine, removes waste & balances Sodium
• Increases blood volume, increases BP
• Hydrated - less ADH less H2O absorbed, dilute urine