Biology 105 Exam 2 Study Guide PDF

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Dr. Josephine Kurdziel...

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Biology 105 Exam 2 Study Guide  1. Vitamins 2. Minerals 3. Summary of Roles

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Vitamins  ● Vitamin A ○ Functions: Antioxidant, Immune Function, Bone Growth and Maintenance, Vision ■ Vision ● Key component of rhodopsin protein that detects light in our eyes ○ Retinal is a key component of rhodopsin ○ Rhodopsin is a visual pigment made of retinal and the protein opsin ○ When light strikes rhodopsin, retinal changes its shape (from cis to trans) ○ A nerve impulse sends the visual signal to the brain; Retinal is then released from rhodopsin to form opsin; Some retinal is lost ○ Opsin must now be recharged by the addition of another molecule of retinal is cis formation ■ Bone Growth and Maintenance ● Micronutrient for connective tissues, helps bone health ● Functions as a hormone ○ Involved in the synthesis of proteins ■ Particularly important to collagen synthesis, epithelial cells, and skin health, which form the skin and mucous membranes inside the body that act as physical barriers ■ Immune Function ● Protects against infections by ensuring the effectiveness of mechanical barriers (eg. skin) ● Increases the production and efficacy of B and T cells (white blood cells in specific immune responses), and macrophages and neutrophils ■ Antioxidant ○ Deficiency: ■ Vitamin A deficiency delays the reformation of cis-retinal-containing rhodopsin and night vision is slow to recover after exposure to a bright light ■ Hypovitaminosis A ● Scarring of cornea ● Night blindness ● Permanent blindness ● Impaired immunity ● Dry and scaly skin ○ Toxicity:

■ Hypervitaminosis A ● Can cause osteoporosis ● Comes mostly from supplements, animal foods ● Can cause birth defects if doses above UL are consumed during pregnancy ● Excess of carotenoids (plant sources) does not cause toxicity, but they turn skin yellow ○ Other important details: ■ Fat-soluble ■ Stored primarily in the liver ■ Composed of retinoids and several carotenoids ● Retinoids ○ Preformed (preformed, meaning already in active form) ■ Retinol ■ Retinal (reversibly converted from retinol) ■ Retinoic acid (irreversibly converted from retinal) ● Carotenoids ○ Plant forms of vitamin A ■ Carotenoids such as beta-carotene ○ Provitamin, not in active form (precursor but our cells can convert it to the active form) ■ Beta-carotene ● Vitamin B1 / Thiamin ○ Functions: Blood Clotting, Oxygen Transport, Nerve Health, Fluid Balance, Energy Metabolism ■ Energy Metabolism ■ Synthesis of RNA and DNA ■ Nerve Health ● Production of neurotransmitters ○ Deficiency: ■ Beriberi (rare in the US due to fortification of grains) ● Causes severe muscle wasting, fatigue, and neurological problems ■ Wernicke-Korsakoff syndrome ● Occurs in people with alcohol use disorders ● Causes severe neurological disturbances ● Alcohol decreases thiamin absorption, increases excretion in the urine, and decreases conversion of thiamin into its coenzyme form ○ Toxicity: None known, no UL set ○ Other Important Details:

■ Functions as a coenzyme ■ Water-soluble ● Vitamin B2 / Riboflavin ○ Functions: Antioxidants, Energy metabolism ■ Energy metabolism ■ Antioxidant ● Coenzyme for an enzyme with antioxidant function ○ Deficiency: ■ Ariboflavinosis symptoms ● Cracks on lips and corners of the mouth ● Swelling of the mouth and sore throat ○ Toxicity: None known, no UL ○ Other Important Details: ■ Functions as a coenzyme ■ Water-soluble ● Vitamin B3 / Niacin ○ Functions: Energy Metabolism ■ Energy metabolism ■ DNA repair ○ Deficiency: ■ Pellagra (symptoms: 3Ds) ● Scaly skin, mouth sores, fatigue, diarrhea ● Chronic deficiency leads to dementia ○ Toxicity: ■ From supplement use ● Face flushing, gastrointestinal effects, liver damage ○ Other Important Details: ■ Functions as a coenzyme ■ Water-soluble ● Vitamin B5 / Pantothenic Acid ○ Functions: Nerve Health, Energy Metabolism ■ Energy Metabolism ■ Nerve Health ● Synthesis of two neurotransmitters ○ Deficiency: Rare in USA ■ Neurological problems ○ Toxicity: None known, no UL ○ Other Important Details: ■ Functions as a coenzyme

■ Water-soluble ● Vitamin B6 / Pyridoxine ○ Functions: Immune Function, Nerve Health, Oxygen Transport, Energy Metabolism ■ Immune Function ● Production of B and T cells and antibodies (specific immune responses) ■ Energy Metabolism ● Metabolizes tryptophan (amino acid) to niacin (B3) ■ Nerve Health ● Synthesis of neurotransmitters ■ Oxygen Transport ● Production of hemoglobin ● Can prevent anemia ○ Deficiency: ■ Anemia (hemoglobin production) ■ Impaired immune function ■ Weakness ■ Dermatitis ■ Neurological disorders ○ Toxicity: ■ Supplements above the UL ■ Numbness in hands and feet ■ Sometimes irreversible nerve damage ○ Other Important Details: ■ Functions as a coenzyme ■ Water-soluble ● Vitamin B7 / Biotin ○ Functions: Immune Function, Energy Metabolism, Nerve Health ■ Immune Function ● Maintenance of normal skin, mucous membranes, hair and fingernails ■ Energy Metabolism ■ Nerve Health ● Myelin production ○ Deficiency: ■ Depression ■ Neurological symptoms ■ Dermatitis, hair loss ○ Toxicity: None known, no UL ○ Other Important Details:

■ Functions as a coenzyme ■ Water-soluble ● Vitamin B9 / Folate (Folic Acid in supplements) ○ Functions: Immune Function, Oxygen Transport, Energy Metabolism ■ Energy Metabolism ● Acts as a coenzyme in the metabolism of certain amino acids ■ Normal cell division and development ■ DNA and RNA synthesis ■ DNA repair ■ Immune Function ● Normal immune system function; innate immune response ■ Oxygen Transport ● Can prevent anemia ○ Deficiency: ■ Megaloblastic anemia (large immature red blood cells that are not functional) ■ During pregnancy, there is an increased risk of birth defects (abnormalities) of brain or spinal cord ■ Reduced immune function ○ Toxicity: ■ Masks vitamin B12 deficiency symptoms ○ Other Important Details: ■ Functions as a coenzyme ■ Water-soluble ● Vitamin B12 / Cobalamin ○ Functions: Nerve Health, Oxygen Transport, Energy Metabolism, Immune Function ■ Energy Metabolism ■ Nerve Health ● Absorption ○ Requires stomach acid to break it from the protein ○ Intrinsic factor (protein) must be active for it to be absorbed in the small intestine ● Maintains neural sheaths ■ Oxygen Transport ● Can prevent anemia ■ Immune Function ● Normal immune system function; innate immune response ● Important to the functioning of vitamin B9 (folate) ○ Deficiency: ■ Megaloblastic anemia

■ Nerve damage, neurological disorders ■ Reduced immune function ○ Toxicity: None known, no UL ○ Other Important Details: ■ Bound to animal proteins ■ Functions as a coenzyme ■ Water-soluble ● Choline ○ Functions: Nerve Health ■ Forms neurotransmitter acetylcholine ■ Is part of phospholipids in cell membranes ■ Intertwined with functions of folate (B9) and vitamin B12 ○ Deficiency: ■ Liver damage ○ Toxicity ■ Only through supplementation ■ Fishy body odor ■ At very high levels: blood pressure drop ○ Other Important Details: ■ Water-soluble ■ Neither a vitamin or mineral ● Vitamin C ○ Functions: Antioxidants, Bone Growth and Maintenance, Immune Function ■ Antioxidant ■ Aids in hormone production ■ Bone Growth and Maintenance ● Involved in collagen synthesis ■ Enhances iron absorption ■ Immune Function ● Required for the synthesis of collagen, an important structural component of connective tissues, which lie under the skin, blood vessels, bone, etc. ○ Deficiency: ■ Scurvy Symptoms ● Anemia (fatigue, tired due to too few red blood cells) ● Subcutaneous bleeding ● Bleeding gums ● Bruising ● Joint pain

● Fragile bones ● Immunity problems ○ Toxicity: ■ Diarrhea ■ Bloating ■ Increase risk of kidney stones ○ Other Important Details: ■ Functions as a coenzyme ■ Water-soluble ● Vitamin D ○ Functions: Bone Growth and Maintenance, Immune Function ■ Bone Growth and Maintenance ● Interacts with vitamins A and C to maintain good bone health ● Maintains blood concentrations of minerals involved in bone development ● Increases muscle strength and function in the elderly, and appears to reduce the risk of falls ● Necessary for regulating cardiovascular function ● May reduce the risk of a number of important diseases, including cancer, autoimmune diseases, kidney disease, type 2 diabetes, and even cardiovascular disease ● Acts as a hormone (calcitriol) ● Bone Remodeling ○ Vitamin D regulates calcium levels and phosphate levels ■ Form calcium/phosphorus crystals ■ Crystals of bone mineral deposited on a protein matrix ■ Vitamin D Activation ● Calcitriol/Active Vitamin D: fully activated form from the kidney ● Vitamin D must be metabolized to its active form by the liver and kidneys ● Inactive vitamin D is synthesized by the skin (when exposed to UV light) and consumed in the diet ● Inactive vitamin D enters the circulation and is transported to the liver ● Conversion to the active form of vitamin D begins in the liver ● The active hormonal form of vitamin D is produced in the kidneys ■ Vitamin D regulates blood calcium levels ● Parathyroid glands: Parathyroid hormone (PTH) is released from the parathyroid glands in response to low blood calcium levels, stimulating the kidneys to increase the production of active vitamin D

● When calcium concentration in blood decrease, more of vitamin D is converted into the active hormonal form, calcitriol ● Kidney: Activated vitamin D increases calcium uptake from urine (synthesis of calcitriol) ● Bone: Activated vitamin D increases calcium release from bone (+PTH) ● Intestine: Activated vitamin D increases absorption of calcium from the intestines ● Therefore: ○ Calcitriol increases absorption of calcium in the small intestine ○ Calcitriol and parathyroid hormone (PTH): ■ Decrease calcium excretion by the kidneys ■ Increase calcium release from bone ■ Immune Function ● Enhances innate immunity: health of macrophages ○ Deficiency: ■ Risk factors ● Those who avoid vitamin D–fortified dairy products ● People with dark skin ● Those with little sun exposure, or who regularly use sunscreen ● Infants who are exclusively breast-fed ● The elderly ■ Can cause serious bone diseases ● Rickets: A condition typically associated with bone malformations in children ● Osteomalacia: Where bone mineral is being depleted, causing the bones to become soft or weak and putting people at risk of fractures or falls, as well as creating pain in the pelvis, lower back, and legs ○ Toxicity: ■ Hypervitaminosis D (likely from supplement use) ● Symptoms ○ Loss of appetite ○ Weight loss ○ Irregular heartbeat ○ Frequent urination ● Results in increased urination, irregular heartbeat, increased blood calcium levels, increased CVD risk ○ Other Important Details: ■ Fat-soluble

■ Made by human cells ■ It can be produced in the skin from cholesterol with exposure to ultraviolet (UV) light ■ Whether through synthesis in the skin or through foods, vitamin D must be activated in the kidneys and liver to fulfill its biological functions in the body ● Vitamin E ○ Functions: Antioxidant, Immune Function, Nerve Health ■ Antioxidant ● Important antioxidant that neutralizes free radicals and breaks the chain of oxidative damage ■ Immune Function ● Affects the production of enzymes in white blood cells and innate immune response ● Protects B and T lymphocytes (specific immune responses) ■ Nerve Health ● Protects nerve cells ○ Deficiency: Rare ○ Toxicity: ■ Caused by high supplement intake ■ Increases tendency to bleed ○ Other Important Details: ■ Fat-soluble ■ Tocopherols ■ Component of cell membranes ● Vitamin K ○ Functions: Blood Clotting, Bone Growth and Maintenance, ■ Blood clotting ● Needed for synthesis of fibrin, a protein for blood clotting ■ Bone maintenance ● Modifies bone proteins so minerals can attach ■ Antioxidant ○ Deficiency: ■ Hemorrhaging ● Severe blood loss which can be fatal if not controlled ○ Toxicity: None known, no UL set ○ Other Important Details: ■ Functions as a coenzyme ■ Made by our gut microbiome/bacteria in the large intestine 

Minerals  ● Calcium ○ Functions: Blood Clotting, Bone Growth and Maintenance, Nerve Health ■ Blood Clotting ● Cofactor for enzymes involved in the synthesis of fibrin (protein involved in blood clotting) ● Normal blood clotting ● Normal blood vessel function ● Absorption and use of other micronutrients such as vitamin D, vitamin K, magnesium, and phosphorous ■ Bone Growth and Maintenance ● Strengthening bone and teeth ■ Nerve Health ● Functions in muscle contraction and nerve transmission ■ Also affects absorption of vitamins D and K, and the minerals magnesium and phosphorus ○ Deficiency: ■ Osteoporosis ○ Toxicity: ■ Hypercalcemia: Blood calcium levels are too high; Can cause calcification of blood vessels ● Constipation (GI problems) ● Interference with iron absorption (decreases it) ■ Calcium deposits in blood vessels; increases risk of CVD ■ At high doses, negative neurological effects ○ Other Important Details: ■ Major mineral ■ Most abundant mineral in the body ● 99% in bone and teeth ● 1% in body cells and fluids ■ Review vitamin D role in maintaining blood calcium levels ● Chloride ○ Functions: Fluid balance ■ Fluid balance ● Electrolyte ● Higher concentrations outside cells; helps regulate fluid balance in the body ■ Important for digestion

● Half of hydrochloric acid (HCl) ○ Deficiency: Rare in the US ○ Toxicity: ■ Over consumption of salt can cause hypertension and increased risk of CVD ○ Other Important Details: ■ Major mineral ■ Half of the mineral composition of table salt (NaCl) ■ Found primarily in extracellular fluids ■ Abundant in the diet with sodium ● Copper ○ Functions: Energy Metabolism, Immune Function, Antioxidant ■ Energy Metabolism ● Cofactor for enzymes involved ■ Immune Function (physical barriers) ● Cofactor for enzymes involved in the formation of connective tissues (collagen) ■ Antioxidant ● Cofactor for enzymes with antioxidant functions ■ Regulation of iron storage and transport ■ Cofactor in oxygen-dependent enzymes ○ Deficiency: ■ Anemia ■ Impaired immune response, reduced wound healing ■ Osteoporosis ○ Toxicity: Very rare in USA ■ At very high doses, cause GI issues: nausea, vomiting, diarrhea ○ Other Important Details: ■ Trace mineral ■ Functions as a cofactor ● Iron ○ Functions: Immune Function, Oxygen Transport ■ Immune Function ● Normal function of innate immune system ● Production of free radicals in innate immune system used to kill bacteria ■ Oxygen Transport ● Component of hemoglobin, a protein in red blood cells that binds to oxygen, and red blood cells distribute oxygen to all body cells ● Can prevent anemia

○ Deficiency: ■ Iron deficiency anemia ● Caused by blood loss or insufficient iron intake ● High-risk groups: children, pregnant, and menstruating women ● Symptoms: Tired, out of breath, poor performance, and slow cognitive and social development ■ Impaired immune function ○ Toxicity: ■ Causes GI issues: diarrhea, constipation, nausea, vomiting ■ In adults iron toxicity causes apathy, fatigue, liver damage, and immune problems ■ Iron poisoning in children ● Can result in unintentional death in children ● Symptoms: nausea, vomiting, diarrhea, rapid heartbeat, dizziness, shock, and confusion ○ Other Important Details: ■ Most abundant trace mineral ■ Functions as a cofactor ■ Component of many enzymes ■ Types ● Heme iron (source: animal foods) ○ Hemoglobin ○ Myoglobin ● Non-heme iron (source: animal and plant foods) ■ Iron in the body ● Hemoglobin: Oxygen carrier in the bloodstream (found in red blood cells) ● Myoglobin: Oxygen supplier in muscle tissue ● Oxygen binds to heme in hemoglobin and myoglobin ■ Iron Sources ● Plant foods only contain non-heme iron ■ Iron Absorption ● Increased by vitamin C, acids, and meat ● Decreased by soy proteins, phytates, and polyphenols, as well as calcium intake ● Potassium ○ Functions: Fluid Balance ■ Fluid Balance ● Electrolyte

● Higher concentrations inside cells, helps regulate fluid balance in the body ■ Important for muscle contractions, aids in nutrient transport ■ Helping maintain electrical activity of the heart ■ May counter effects of excess sodium on blood pressure ○ Deficiency: ■ Severe depletion (usually from excessive fluid loss through vomiting, diarrhea, use of diuretics, or kidney disorders) causes: ● Fatigue ● Muscle weakness and muscle cramps ● Abnormal heart rhythms ● Increased risks of CVD ○ Toxicity: ■ Only from supplement misuse ■ Symptoms ● GI issues: abdominal cramps, nausea and/or diarrhea ● Abnormal heart rhythm ○ Other Important Details: ■ Major mineral ■ Primary electrolyte inside cells ■ Acting as a cofactor for certain enzymes ● Magnesium ○ Functions: Energy Metabolism, Bone Growth and Maintenance ■ Bone Growth and Maintenance ● 50% to 60% is found in bones; important bone mineral; maintains bone health ■ Role in protein production ■ Necessary in activating vitamin D ■ Role in the transport of ions across cell membranes (for muscle contraction, nerve impulse conduction, and maintaining heart rhythm) ■ Energy Metabolism ● Cofactor for enzymes involved in energy metabolism ○ Deficiency: ■ Increased risk of osteoporosis ■ Muscle cramps ■ Seizures ■ Increased risks of CVD ○ Toxicity: ■ Rare in US

■ High doses from supplements can cause diarrhea ■ At very high doses can cause kidney failure ○ Other Important Details: ■ Major mineral ■ Cofactor in more than 300 chemical reactions ● Manganese ○ Functions: Antioxidant, Immune Function, Bone Growth and Maintenance ■ Antioxidant ● Cofactor for enzymes with antioxidant functions ■ Bone Growth and Maintenance ● Cofactor for enzymes involved in the synthesis of bone proteins ■ Immune Function ● Cofactor for enzymes involved in wound healing (physical barriers) ○ Deficiency: ■ Bone malformation ○ Toxicity: ■ Neurological problems ○ Other Important Details: ■ Trace mineral ■ Functions as a cofactor ● Potassium ○ Functions: ■ Fluid Balance ● Electrolyte ● Higher concentrations inside cells, helps regulate fluid balance in the body ● Important for muscle contractions, aids in nutrient transport ● Helping maintain electrical activity of the heart ■ May counter effects of excess sodium on blood pressure ○ Deficiency: ■ Mild forms increase risk of hypertension ■ Severe depletion (usually from excessive fluid loss through vomiting, diarrhea, use of diuretics, or kidney disorders) causes: ● Fatigue ● Muscle weakness and muscle cramps ● Abnormal heart rhythms ● Increased risks of CVD ○ Toxicity: ■ Only from supplement misuse

● GI issues: abdominal cramps, nausea, diarrhea ● Abnormal heart rhythm ○ Other important details: ■ Major mineral ■ Primary electrolyte inside cells ■ Acts as a cofactor for certain enzymes ● Phosphorus ○ Functions: Bone Growth and Maintenance, Energy Metabolism ■ Bone Growth and Maintenance ● Important bone mineral ● Strengthens bones and teeth ● Important for bone health component of cartilage, phospholipids in cell membranes, DNA, and RNA ■ Energy Metabolism ● Cofactor for enzymes involved in energy metabolism ■ Regulates many enzymes ■ Helps maintain acid-base balance ○ Deficiency: Very rare in USA ■ Poor bone mineralization ■ Muscle weakness ○ Toxicity: ■ Decreased bone mineral density ○ Other Important Details: ■ Major mineral, found in every cell of the body ■ Functions as a cofactor ■ Phosphorus is found in protein-rich foods ● Sodium ○ Functions: Fluid Balance, Nerve Health ■ Fluid Balance ● Electrolyte ● Higher concentrations outside cells, helps regulate fluid balance in the body ■ Regulates blood pressure, transmits nerve impulses, aids in nutrient transport ■ Important for muscle contractions ○ Deficiency: Rare in USA ■ Many Americans consume too much salt (NaCl) from processed foods and restaurant meals ○ ...