Which hormone increases calcium levels in the bloodstream?
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Parathyroid hormone.
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Which hormone increases calcium levels in the bloodstream?
Parathyroid hormone.
What proteins interact during muscle contraction?
Actin and myosin.
How many ATP are produced in the Krebs cycle?
A net of 2 ATP.
What happens when myosin binds to actin?
It undergoes a power stroke, pulling the actin filament towards the center of the sarcomere.
What occurs during excitation-contraction coupling in skeletal muscles?
Generation of end plate potential, depolarization along the Sarco-tubular system, hydrolysis of ATP, but NOT binding of calcium ions to myosin.
Where does oxidative phosphorylation occur?
In the inner mitochondrial membrane of eukaryotic cells.
What process drives ATP synthesis during oxidative phosphorylation?
Chemiosmosis.
What is the function of secretin?
It regulates the secretion of pancreatic enzymes and bicarbonate, and inhibits gastric acid secretion.
What is produced during the Krebs cycle?
ATP, NADH, FADH2, and carbon dioxide.
Which gland secretes the enzyme that digests carbohydrates in the oral cavity?
Parotid gland.
What is fibrinolysis?
The process where plasmin breaks down fibrin strands in a clot as the wound heals.
What is hemophilia?
A genetic bleeding disorder characterized by the inability of blood to clot properly.
What is glycogenolysis?
The breakdown of glycogen, a stored form of glucose.
Which blood vessels have the highest cross-sectional area?
Capillaries.
What are the four main blood types in the ABO system?
A, B, AB, and O.
Which hormone is released by the pancreas to break down lipids?
Lipase.
What results from the sliding of actin filaments past myosin filaments?
The shortening (contraction) of the sarcomere and the entire muscle fiber.
Which part of the nervous system prepares the body for emergency responses?
Sympathetic nervous system.
What is the condition characterized by yellowish discoloration of the skin and eyes?
Jaundice.
What is primary active transport?
It uses ATP directly to transport molecules across the cell membrane through specific protein pumps, such as the sodium-potassium pump.
What are anticoagulant proteins and give an example?
Proteins that inhibit clotting factors; examples include antithrombin and protein C.
What is exocytosis?
The process where cells release substances from vesicles into the extracellular environment.
What is physiology?
The branch of biology that studies the normal functions of living organisms and their parts.
What are the main components of the electron transport chain?
Complex I (NADH dehydrogenase), Complex II (succinate dehydrogenase), Complex III (cytochrome bc1 complex), Complex IV (cytochrome c oxidase), and ATP synthase.
What regulates the blood clotting process?
Positive and negative feedback mechanisms.
What stimulates the release of secretin?
The presence of acidic chyme in the duodenum.
Where does glycogenolysis mainly occur?
In the liver and muscles.
What enzyme initiates glycogenolysis?
Glycogen phosphorylase.
What are the mechanisms of cell communication?
Direct contact, chemical signaling, and electrical signaling.
What is the primary function of the kidneys in the human body?
Filtration of blood and excretion of waste products.
What is gluconeogenesis?
A metabolic pathway that produces glucose from non-carbohydrate precursors, primarily in the liver and kidneys.
What is thrombosis?
The formation of a blood clot (thrombus) within a blood vessel, obstructing normal blood flow.
What happens in an isotonic solution?
The concentration of solutes inside and outside the cell is equal, resulting in no net movement of water and maintaining the cell's normal shape and volume.
What initiates muscle contraction?
An action potential traveling along motor neurons to the muscle fibers.
What happens to calcium ions after the action potential ceases?
They are actively pumped back into the sarcoplasmic reticulum, leading to muscle relaxation.
What is the primary function of pulmonary circulation?
To transport deoxygenated blood from the heart to the lungs for oxygenation and return oxygenated blood back to the heart.
What is the difference between paracrine and autocrine signaling?
Paracrine signaling acts on nearby target cells, while autocrine signaling affects the signaling cell itself.
What is secondary active transport?
It couples the movement of one molecule against its concentration gradient to the movement of another molecule down its concentration gradient, utilizing energy stored in the electrochemical gradient.
What is diffusion?
A form of passive transport where molecules move from an area of higher concentration to an area of lower concentration.
What is osmosis?
A passive transport specific to water molecules, moving across a selectively permeable membrane.
What is ghrelin known as?
The hunger hormone.
What occurs in a hypertonic solution?
The concentration of solutes outside the cell is higher, causing water to move out, leading to cell shrinkage or death.
What initiates vitamin D synthesis in the skin?
Exposure to ultraviolet B (UVB) radiation from sunlight.
Where does the Krebs Cycle take place?
In the mitochondrial matrix.
What occurs during ventilation?
Movement of air into and out of the lungs, involving diaphragm contraction and rib muscle expansion during inhalation, and relaxation during exhalation.
What determines blood types?
The presence or absence of specific antigens on the surface of red blood cells.
What is the primary function of blood clotting?
To prevent excessive bleeding and promote wound healing.
What is responsible for the transport of oxygen in the bloodstream?
Hemoglobin.
How many ATP molecules are produced per glucose molecule during oxidative phosphorylation?
About 32-34 ATP molecules.
What are the two main types of cell transport?
Passive transport and active transport.
How many main blood types result from the combination of the ABO system and Rh factor?
Eight main blood types: A+, A-, B+, B-, AB+, AB-, O+, and O-.
What is hemoglobin?
The primary blood pigment responsible for the red color, found in red blood cells.
Where does protein digestion initially occur in the digestive system?
Stomach.
What enzyme catalyzes the conversion of calcidiol to calcitriol?
1-alpha-hydroxylase.
Where are action potentials generated in a nerve cell?
Axon hillock.
Where does gas exchange occur?
In the alveoli, tiny air sacs in the lungs.
What is the terminal button in the nervous system?
The part of a neuron that releases neurotransmitters.
What is homeostasis?
The stable internal environment of an organism.
What is the final electron acceptor in the electron transport chain?
Oxygen.
What antibodies are present in Type A blood?
Anti-B antibodies.
What antigens are present in Type AB blood?
Both A and B antigens.
What cellular characteristic is utilized in filtration?
Semipermeable membrane.
What is the role of cholecystokinin?
It triggers gallbladder contraction to release bile and promotes satiety.
What role do carrier proteins play in facilitated diffusion?
They assist in the transport of molecules across the cell membrane.
Which hormones promote gluconeogenesis?
Glucagon and cortisol.
Which hormone stimulates glycogenolysis in the liver?
Glucagon.
Which hormone promotes the conversion of calcidiol to calcitriol?
Parathyroid hormone (PTH).
What is the basic contractile unit of a muscle?
The sarcomere.
At what levels does physiology study functions?
Cellular, tissue, organ, and systemic levels.
What is active transport?
The movement of molecules against their concentration gradient, requiring energy, usually in the form of ATP.
What role does gastrin play in the digestive system?
It regulates gastric acid secretion and the movement of food through the digestive system.
What is the net ATP yield from fermentation?
2 ATPs per glucose.
What are the two types of endocytosis?
Phagocytosis (cellular 'eating') and pinocytosis (cellular 'drinking').
When a cell is polarized, what is true about voltage-gated sodium channels?
They are closed by their activation agents.
How does ghrelin affect appetite?
It stimulates appetite and regulates food intake.
How many ATP molecules are produced during cellular respiration?
A total of 36-38 ATP molecules per molecule of glucose, depending on cell type and conditions.
What is the term for acid-base imbalance in a patient?
Metabolic acidosis.
What is respiratory acidosis?
A condition characterized by an excess of carbon dioxide in the blood, leading to increased blood acidity.
What is metabolic alkalosis?
A condition characterized by elevated pH and decreased blood acidity, often due to excessive loss of acids or increased bicarbonate levels.
What provides the energy required for myosin heads to detach from actin?
ATP.
What are some effects of the sympathetic nervous system?
Widening of the trachea, increased heart rate, and liver stimulation for glucose release.
What triggers the release of gastrin?
The presence of food in the stomach, particularly proteins.
What is endocytosis?
A process by which cells take in substances from the external environment by engulfing them with the cell membrane, forming vesicles.
Which of the following is an example of secondary transport?
Na – glucose cotransport.
What is the Rh factor?
An antigen that determines whether a person is Rh-positive (+) or Rh-negative (-).
What are the main precursors for gluconeogenesis?
Lactate, amino acids, and glycerol.
What is arterial thrombosis and its potential consequences?
Clot formation in an artery, which can lead to myocardial infarction (heart attack) or stroke.
What does a person with blood type AB and Rh positive indicate?
No ABO antibodies and RH antibody.
What is cellular respiration?
The process by which cells convert glucose and oxygen into energy, carbon dioxide, and water.
In which blood vessels is the velocity of blood flow fastest?
Aorta.
What is cellular respiration?
The process within cells that utilizes oxygen to produce energy (ATP) and releases carbon dioxide as a byproduct.
What is chyme?
A semi-liquid substance formed in the stomach by mixing food with gastric juices.
What can excessive hemolysis lead to?
Anemia, hypoxia, and jaundice, but NOT hypertension.
What genetic disorder causes abnormal hemoglobin and sickle-shaped red blood cells?
Sickle cell anemia.
What is endocrine signaling?
The release of hormones into the bloodstream that travel to distant target cells.
What is bilirubin and how is it produced?
A yellowish pigment produced from the breakdown of heme, primarily processed by the liver and excreted in bile.
What happens in a hypotonic solution?
The concentration of solutes outside the cell is lower, resulting in water moving into the cell, which may cause it to swell and burst.
What role does calcitriol play in the body?
It acts as a hormone regulating calcium and phosphate homeostasis.
What is the function of villi in the small intestine?
Villi absorb nutrients across the lining of the small intestine into the bloodstream.
What types of fermentation can cells undergo in the absence of oxygen?
Lactic acid fermentation or alcohol fermentation.
What is cellular tonicity?
The relative concentration of solutes inside and outside a cell, determining the movement of water across the cell membrane.
Where are ligand-gated ion channels normally present in a nerve cell?
Dendrite.
What is the role of calcium ions in muscle contraction?
They bind to troponin, causing a conformational change that exposes binding sites on actin filaments.
What is the precursor molecule converted into pre-vitamin D3?
7-dehydrocholesterol.
What are the four main steps of respiration?
Ventilation, gas exchange, transport of gases, and cellular respiration.
What is the main purpose of gluconeogenesis?
To maintain blood glucose levels during fasting, prolonged exercise, or low carbohydrate intake.
What is venous thrombosis?
Clot formation in a vein, commonly in the deep veins of the legs (DVT) or in the lungs (pulmonary embolism).
What is an embolism?
Obstruction of a blood vessel by an embolus, which can be a dislodged solid, liquid, or gas.
What occurs during glycolysis?
Glycolysis breaks down one molecule of glucose into two molecules of pyruvate, producing a net of 2 ATP and NADH.
What are the three parts of the small intestine?
Duodenum, jejunum, and ileum.
What type of transport uses carrier proteins but does not require mitochondrial activity?
Facilitated diffusion.
What causes methemoglobin to form?
When iron in hemoglobin is in the oxidized (ferric) state, causing the blood to appear brownish.
What neurotransmitter is released at the neuromuscular junction?
Acetylcholine.
In response to hypoxia, which organ secretes erythropoietin?
Kidney.
What is the function of the sarcoplasmic reticulum?
It stores calcium ions (Ca2+).
What are the three stages of cellular respiration?
Glycolysis, Krebs Cycle, and Electron Transport Chain.
What happens to undigested waste in the large intestine?
Water is reabsorbed, and waste material is formed into feces.
What is respiration?
The process by which living organisms obtain oxygen and release carbon dioxide, involving inhalation and exhalation.
What role does bile play in digestion?
Bile from the liver aids in the breakdown of fats in the duodenum.
What is the function of calcitonin?
It reduces calcium levels by inhibiting osteoclast activity and decreasing calcium reabsorption in the kidneys.
What is the role of hemoglobin in gas transport?
Oxygen binds to hemoglobin in red blood cells to form oxyhemoglobin, which is transported to tissues.
What is the digestive process?
The breakdown of food into smaller, absorbable molecules and the absorption of nutrients by the body.
What is gastrin?
A hormone produced by G cells in the stomach that regulates digestive processes.