Podcast Beta
Questions and Answers
What percentage of the whole blood is composed of blood plasma?
What is the primary function of albumins in blood plasma?
Which type of globulin is primarily involved in antibody production?
What is the main energy source in blood plasma?
Signup and view all the answers
What is the primary function of fibrinogen in blood plasma?
Signup and view all the answers
What is the term for the pressure created by proteins in blood plasma?
Signup and view all the answers
Which of the following is NOT a type of immune substance found in blood plasma?
Signup and view all the answers
What is the primary goal of structural homeostasis in the body?
Signup and view all the answers
Which system is responsible for providing genetic homeostasis in the body?
Signup and view all the answers
What is the primary function of homeostats in the body?
Signup and view all the answers
Which of the following is NOT a type of homeostatic regulation in the body?
Signup and view all the answers
What is the primary function of the kidneys in maintaining homeostasis?
Signup and view all the answers
Which hormone is involved in the regulation of blood sugar levels in the body?
Signup and view all the answers
What is the primary function of the hypothalamus in thermoregulation?
Signup and view all the answers
What is the primary function of osmoregulation in the body?
Signup and view all the answers
What is the primary function of cholesterol in the body?
Signup and view all the answers
What is the main function of the sarcoplasmic reticulum in muscle fibers?
Signup and view all the answers
What is the primary component of the myofibrils in skeletal muscle cells?
Signup and view all the answers
What is the function of troponin in muscle contraction?
Signup and view all the answers
What is the term for the smallest contractile unit of a muscle fiber?
Signup and view all the answers
What is the term for the theory that explains how muscles contract to produce force?
Signup and view all the answers
What is the primary function of the T-tubules in muscle fibers?
Signup and view all the answers
What is the term for the regulatory protein that binds to actin filaments and regulates muscle contraction?
Signup and view all the answers
What is the primary mechanism by which the kidneys influence systemic blood pressure?
Signup and view all the answers
What is the primary function of the kidneys in maintaining pH homeostasis?
Signup and view all the answers
What is the term for the gap between the presynaptic and postsynaptic membranes in a synapse?
Signup and view all the answers
What is the primary function of albumins in blood plasma?
Signup and view all the answers
What is the term for the proteins used in a chemical synapse to transmit impulses?
Signup and view all the answers
What is the percentage of globulins in blood plasma proteins?
Signup and view all the answers
What is the function of the postsynaptic membrane in a synapse?
Signup and view all the answers
What is the term for the junction between a nerve and a muscle or two nerves?
Signup and view all the answers
Which component of blood plasma plays a crucial role in maintaining the normal exchange of water and salts in the capillaries?
Signup and view all the answers
What is the primary function of agglutinins in blood plasma?
Signup and view all the answers
Which blood plasma protein is responsible for transporting hormones that are poorly soluble in water?
Signup and view all the answers
What is the role of oncotic pressure in blood plasma?
Signup and view all the answers
Which organs play a crucial role in maintaining the osmotic pressure in blood plasma?
Signup and view all the answers
What is the primary function of plasma proteins in transporting substances?
Signup and view all the answers
What percentage of the total osmotic pressure in blood plasma is attributed to oncotic pressure?
Signup and view all the answers
Which of the following is NOT a function of plasma proteins?
Signup and view all the answers
What is the primary function of HCl in the stomach?
Signup and view all the answers
What is the ideal environment created by the rumen and reticulum?
Signup and view all the answers
What is the consequence of a lack of HCl in gastric juice?
Signup and view all the answers
What is the function of the hormone secretin promoted by HCl in the duodenum?
Signup and view all the answers
What is the pH range of the stomach?
Signup and view all the answers
What is the function of HCl in terms of bactericidal function?
Signup and view all the answers
What is the term for a deficiency of HCl in gastric juice?
Signup and view all the answers
What is the primary role of the parotid salivary gland in the development of forestomachs in ruminants?
Signup and view all the answers
What is the function of the internal antianemic factor produced by the stomach?
Signup and view all the answers
What is the optimal pH range for microbial fermentation in the rumen of ruminants?
Signup and view all the answers
What is the pH range of the forestomachs?
Signup and view all the answers
What is the significance of pH regulation in the forestomachs of ruminants?
Signup and view all the answers
What is the primary function of inhibitory neurons in the central nervous system?
Signup and view all the answers
What is the role of HCl in the regulation of further evacuation of gastric contents to the duodenum?
Signup and view all the answers
What is the primary mechanism of pH maintenance in the rumen of ruminants?
Signup and view all the answers
What is the primary consequence of imbalanced pH levels in the forestomachs of ruminants?
Signup and view all the answers
What is the primary role of the abomasum in the digestive system of ruminants?
Signup and view all the answers
What is the primary significance of pH regulation in the digestive system of animals?
Signup and view all the answers
What is the primary mechanism of inhibitory neurotransmission in the nervous system?
Signup and view all the answers
What is the primary role of buffering agents in the saliva of ruminants?
Signup and view all the answers
What is the primary function of saliva in ruminants?
Signup and view all the answers
What is the optimal ratio of volatile fatty acids in ruminants?
Signup and view all the answers
What is the primary source of energy in ruminants?
Signup and view all the answers
What is the pH range of saliva in ruminants?
Signup and view all the answers
What is the function of the parotid salivary gland in ruminants?
Signup and view all the answers
What is the primary fate of glucose in ruminants?
Signup and view all the answers
Why is the pH of the small intestine alkaline?
Signup and view all the answers
What is the function of volatile fatty acids in ruminants?
Signup and view all the answers
What is the primary site of volatile fatty acid production in ruminants?
Signup and view all the answers
What is the function of baroreceptors and chemoreceptors in the forestomach walls?
Signup and view all the answers
What is the main function of presynaptic inhibition?
Signup and view all the answers
What is the effect of hyperpolarization on a neuron?
Signup and view all the answers
What is the primary function of GABA in the nervous system?
Signup and view all the answers
What is the term for the type of synaptic inhibition that occurs when an inhibitory synaptic knob is located directly on the termination of the presynaptic excitatory fiber?
Signup and view all the answers
What is the term for the period of time during which a neuron is refractory to stimulation?
Signup and view all the answers
What is the primary function of inhibition in the nervous system?
Signup and view all the answers
What is the term for the process by which the nervous system regulates opposing processes?
Signup and view all the answers
What is the term for the type of respiration that involves gas exchange between the air and an organism's cells?
Signup and view all the answers
What is the term for the process of gas exchange between the blood and body cells?
Signup and view all the answers
What is the term for the process by which organic molecules are oxidized to produce CO2, water, and ATP?
Signup and view all the answers
What is the primary difference between physiological sexual maturity and breeding maturity?
Signup and view all the answers
What is the main factor that affects the time of onset of physiological sexual maturity?
Signup and view all the answers
At what percentage of an adult's body weight does breeding maturity typically occur?
Signup and view all the answers
What is the primary function of water in the body, in relation to enzymatic reactions?
Signup and view all the answers
What is the result of breeding an animal immediately after the onset of physiological sexual maturity?
Signup and view all the answers
What determines the permeability of the biological membrane?
Signup and view all the answers
What is the age range for physiological maturity in dogs and cats?
Signup and view all the answers
What is the primary function of the kidneys in maintaining water balance in the body?
Signup and view all the answers
What is the age range for breeding maturity in horses?
Signup and view all the answers
What is the term for the ability of the biological membrane to selectively allow certain substances to pass through?
Signup and view all the answers
What is the primary function of water in the respiratory tract?
Signup and view all the answers
What is the primary function of water in the digestive system?
Signup and view all the answers
Which hormone increases water reabsorption from nephron tubules, resulting in the kidneys retaining water in the body?
Signup and view all the answers
What occurs when water losses exceed water gain, leading to an increase in the concentration of electrolytes in the body fluids?
Signup and view all the answers
Which of the following is a stimulus of thirst in animals?
Signup and view all the answers
What is the result of an increase in capillary permeability due to severe burns?
Signup and view all the answers
Which cells secrete epinephrine, also known as adrenalin?
Signup and view all the answers
What is the term for the abnormal accumulation of interstitial fluid accompanied by swelling?
Signup and view all the answers
What is the effect of testosterone on bone mass?
Signup and view all the answers
Which of the following is NOT a function of the respiratory system?
Signup and view all the answers
What is the primary function of Leydig cells?
Signup and view all the answers
How do the respiratory and cardiovascular systems work together?
Signup and view all the answers
What is the effect of testosterone on male reproductive organs?
Signup and view all the answers
What is the role of the respiratory system in regulating acid-base balance?
Signup and view all the answers
What is the primary function of the respiratory system in regulating blood pH?
Signup and view all the answers
What is the role of the renin-angiotensin-aldosterone system (RAAS) in blood pressure regulation?
Signup and view all the answers
What is the primary function of the liver in thermoregulation?
Signup and view all the answers
What is the role of chemoreceptors in the medulla oblongata and carotid and aortic bodies in the respiratory system?
Signup and view all the answers
What is the primary function of the cardiovascular system in oxygen delivery and CO2 removal?
Signup and view all the answers
What is the role of the lungs in the renin-angiotensin-aldosterone system (RAAS)?
Signup and view all the answers
What is the liver's role in carbohydrate metabolism?
Signup and view all the answers
What is the liver's primary function in protein metabolism?
Signup and view all the answers
What is the liver's role in hormonal regulation?
Signup and view all the answers
What percentage of the liver is dedicated to glycogen storage?
Signup and view all the answers
What is the liver's role in fat metabolism?
Signup and view all the answers
What is the liver's role in synthesizing bile acids?
Signup and view all the answers
What is the liver's role in urea formation?
Signup and view all the answers
What is the liver's role in deamination of amino acids?
Signup and view all the answers
What is the liver's role in cholesterol synthesis?
Signup and view all the answers
What is the liver's role in angiotensinogen synthesis?
Signup and view all the answers
What is the term for the intrinsic property of the heart muscle to depolarize spontaneously, in the absence of an external stimulus?
Signup and view all the answers
What is the range of impulses per minute generated by the sinoatrial node?
Signup and view all the answers
During which phase of the cardiac cycle is the myocardium unable to respond to stimuli?
Signup and view all the answers
What is the term for the ability of a muscle to respond to stimuli when changing from a resting state to functional activity state?
Signup and view all the answers
What happens to the excitability of the heart muscle during the cardiac cycle?
Signup and view all the answers
What is the term for the ability of the myocardium to conduct excitation?
Signup and view all the answers
What determines the force of contraction of the myocardium?
Signup and view all the answers
What is the characteristic of the myocardial cells?
Signup and view all the answers
During which phase of the cardiac action potential is the excitability of the heart muscle slightly increased?
Signup and view all the answers
What is the primary function of the myenteric (Auerbach's) plexus in the enteric nervous system (ENS)?
Signup and view all the answers
What type of enzymes break down proteins into amino acids?
Signup and view all the answers
What is the term for the large Na+ current that rapidly depolarizes the membrane potential during phase 0 of the cardiac action potential?
Signup and view all the answers
Which type of bacteria is involved in the breakdown of cellulose in the forestomach?
Signup and view all the answers
During which phase of the cardiac action potential is the influx of Ca2+ through L-type Ca2+ channels electrically balanced by K+ efflux?
Signup and view all the answers
What is the primary function of the submucosal (Meissner's) plexus in the enteric nervous system (ENS)?
Signup and view all the answers
What is the term for the process by which the breakdown products of digestion are absorbed into the bloodstream and lymph?
Signup and view all the answers
What is the primary function of glucagon in the body?
Signup and view all the answers
What is the effect of insulin on skeletal muscles?
Signup and view all the answers
What is the characteristic of visceral or single-unit smooth muscle?
Signup and view all the answers
What is the effect of glucagon on adipose tissue cells?
Signup and view all the answers
What is the role of β cells in the pancreas?
Signup and view all the answers
What is the primary function of insulin in the liver?
Signup and view all the answers
What is the effect of insulin on lipoprotein lipase in adipose tissue cells?
Signup and view all the answers
What is the primary function of glucagon in the liver?
Signup and view all the answers
What is the primary stimulus for the formation of angiotensin II?
Signup and view all the answers
What is the role of the chloride shift in CO2 transport?
Signup and view all the answers
Which type of thirst is caused by dryness of the mouth and throat?
Signup and view all the answers
What is the primary function of aldosterone in the regulation of water and salt metabolism?
Signup and view all the answers
What is the percentage of CO2 transported in the form of bicarbonate ions?
Signup and view all the answers
What is the primary function of the hypothalamus in regulating water and salt metabolism?
Signup and view all the answers
What is the primary function of epinephrine in the regulation of water and salt metabolism?
Signup and view all the answers
What is the primary function of the central thirst center in the regulation of water and salt metabolism?
Signup and view all the answers
What is the primary function of gap junctions in smooth muscle?
Signup and view all the answers
What is the key difference between multi-unit smooth muscle and single-unit smooth muscle?
Signup and view all the answers
What is the effect of glucocorticoids on the bronchi and bronchioles?
Signup and view all the answers
What is the term for the stage of stress response where the body's ability to produce ACTH and glucocorticoids is depleted?
Signup and view all the answers
What is the primary function of smooth muscle in the walls of hollow and tubular organs?
Signup and view all the answers
What is the term for the sensation of dryness in the mouth and throat associated with a desire for liquids?
Signup and view all the answers
What is the characteristic of smooth muscle that allows it to remain in a state of contraction for a long time?
Signup and view all the answers
What is the primary function of the autonomic nervous system in relation to smooth muscle?
Signup and view all the answers
What is the effect of GH on the uptake of glucose by cells?
Signup and view all the answers
What is the primary function of GH in terms of tissue repair and regeneration?
Signup and view all the answers
What is the role of GH in the maintenance of internal organs?
Signup and view all the answers
Which of the following is a function of carbohydrates in the body?
Signup and view all the answers
What is the primary function of glycogen in the body?
Signup and view all the answers
What is unique about carbohydrate metabolism in ruminants?
Signup and view all the answers
What is the primary function of the absorptive function of the digestive tract?
Signup and view all the answers
What is the term for the period of time during which an organ or cell is incapable of repeating a particular action?
Signup and view all the answers
What is the term for the rapid change in voltage or action potential?
Signup and view all the answers
What is the term for the function of the digestive tract that involves the production of hormones by endocrine cells?
Signup and view all the answers
What is the term for the function of the digestive tract that involves the release of substances or metabolites that have not been used by the body?
Signup and view all the answers
What is the term for the function of the digestive tract that involves the movement of food through the digestive tract?
Signup and view all the answers
What happens to the permeability of the cell membrane to K ions during the repolarization phase of an action potential?
Signup and view all the answers
What is the primary function of growth hormone (GH) in children and adolescents?
Signup and view all the answers
What is the result of Na+ channels deactivating during the repolarization phase of an action potential?
Signup and view all the answers
What is the effect of somatostatin on growth hormone production?
Signup and view all the answers
What is the consequence of a decrease in growth hormone production during the growth period?
Signup and view all the answers
What is the result of the K+ gates staying open longer than necessary during the repolarization phase of an action potential?
Signup and view all the answers
In ruminants, what percentage of carbohydrates are absorbed as glucose into the bloodstream?
Signup and view all the answers
What is the primary source of acetic acid in ruminants?
Signup and view all the answers
What is the main energy source for the central nervous system (CNS) in monogastric animals?
Signup and view all the answers
Where is glycogen primarily stored in the body?
Signup and view all the answers
What is the function of lipoprotein lipase (LPL) in lipid metabolism?
Signup and view all the answers
What is the ratio of volatile fatty acids (VFAs) in the rumen of ruminants?
Signup and view all the answers
What is the primary reason for the decrease in pressure in the pleural cavity during inspiration?
Signup and view all the answers
What is the main function of osmoregulation in the body?
Signup and view all the answers
What is the term for the difference in the concentration of dissolved salts on both sides of a biological membrane?
Signup and view all the answers
What happens to cells when the extracellular fluid becomes hypotonic compared to the intracellular fluid?
Signup and view all the answers
What is the primary role of the kidneys in maintaining osmotic balance in the body?
Signup and view all the answers
What is the term for the process by which the body maintains a constant osmotic pressure in bodily fluids?
Signup and view all the answers
What is the primary function of osmotic pressure in the kidneys?
Signup and view all the answers
What is the highest pressure achieved in the human heart during ventricular systole?
Signup and view all the answers
What is the term for the pressure created by proteins in blood plasma?
Signup and view all the answers
What is the role of the aorta in maintaining blood pressure during total diastole?
Signup and view all the answers
What is the primary function of osmotic pressure in the gastrointestinal tract?
Signup and view all the answers
What is the term for the lowest pressure achieved in the heart during ventricular systole?
Signup and view all the answers
What is the primary function of osmotic pressure in the production of bodily fluids?
Signup and view all the answers
What is the primary function of the right ventricle in the heart?
Signup and view all the answers
What is the role of albumin in the maintenance of blood pressure?
Signup and view all the answers
What is the primary function of osmotic pressure in the maintenance of blood pressure?
Signup and view all the answers
What is the primary cause of muscle fatigue in the 2nd stage of the nerve/muscle preparation experiment?
Signup and view all the answers
What is the byproduct of anaerobic glycolysis that can cause fatigue and soreness in muscles?
Signup and view all the answers
What happens to the contraction amplitude in the myogram when the nerve is irritated repeatedly?
Signup and view all the answers
What is the purpose of anaerobic glycolysis in muscle cells?
Signup and view all the answers
Why does the nerve get tired first in the nerve/muscle preparation experiment?
Signup and view all the answers
What is the primary function of estrogen hormones in the development of female reproductive system?
Signup and view all the answers
What is the effect of high levels of estrogen in the blood on the release of folliberins and FSH?
Signup and view all the answers
What is the primary role of estrogen in the estrus cycle?
Signup and view all the answers
What is the effect of estrogen on the development of mammary glands?
Signup and view all the answers
What is the role of estrogen in preparing the genitalia for copulation and transportation of spermatozoa?
Signup and view all the answers
Study Notes
Blood Plasma Composition
- Blood plasma makes up about 60% of the whole blood
- It is a straw-colored liquid consisting of: • Organic substances (electrolytes, nutrients, proteins, hormones, etc.) • Inorganic substances (electrolytes, salts, etc.) • Dissolved blood gases
- Plasma proteins (7%): • Albumins (~59%): main protein reserve, create colloid osmotic (oncotic) pressure, regulate water exchange, and act as carrier proteins • Globulins (~30%): diverse group of proteins, divided into three groups (α, β, and γ), act as carrier proteins and antibodies • Fibrinogen (3 g/L): plasma protein involved in blood clotting
- Other components: • Nutrients (amino acids, lipids, glucose) • Vitamins, microelements (trace elements) • Metabolic end products (urea, lactic acid, creatinine, bilirubin, CO2, etc.)
Protein Functions in Blood Plasma
- Functions of blood plasma proteins: • Supply of nutrients for the body's plastic and energetic processes • Transport of many substances (bilirubin, fats acids, exogenous substances, including drugs) • Creation of colloid osmotic (oncotic) pressure in the blood plasma • Protective role, especially for globulins • Help to maintain relatively constant blood pH • Plasma proteins transport various substances in the blood • Take part in blood coagulation – fibrinogen
Colloid Osmotic (Oncotic) Blood Pressure
- Created by proteins in the blood plasma
- About 80% results from the albumin fraction, 20% from the globulin, and a tiny amount from the fibrinogen
- Oncotic blood pressure affects: • In capillaries: filtration decreases and reabsorption of H2O increases • pH level: acts as a buffer • Transport: Fe, lipids, hormones, vitamins, etc. • Protective function: immunity, blood clotting factors, etc.
Muscle Contraction
- Muscle cells (fibers) consist of: • Sarcolemma: muscle fiber cell membrane • Sarcoplasm: muscle fiber cytoplasm • Sarcoplasmic Reticulum: smooth endoplasmic reticulum (SER) in the muscle fiber • Transverse Tubules: formed by invaginations of the sarcolemma • Myofibril: bundle of thread-like contractile elements consisting of myofilaments
- Myofilaments: • Thick filaments (myosin): 16nm, during muscle contraction, the myosin heads link the thick and thin filaments together • Thin filaments (actin): 8nm, provide active sites where myosin heads attach during contraction • Elastic filaments (titin): connect myosin to the Z discs • Non-elastic filaments (nebulin): an actin-binding protein, determines the length of thin filaments
- Sliding Filament Theory: actin and myosin filaments within the sarcomeres of muscle fibers bind to create cross-bridges and slide past one another, creating a contraction
Homeostasis
- Definition: the relative constancy of an organism's structure, genetics, and internal environment, and the mechanisms that maintain it
- Types of homeostatic regulation: • Thermoregulation: maintaining the core body temperature • Chemical regulation: balancing the concentration of chemicals like glucose, calcium, acid-base balance, etc. • Osmoregulation: maintaining a constant osmotic pressure inside the body by balancing the concentration of fluids and salts
Urinary System and Homeostasis
- The kidneys perform the following functions: • Filter the blood by removing metabolic wastes • Regulate blood solute concentration (osmolarity) • Assist in the long-term regulation of blood pH • Directly influence systemic blood pressure through their control of blood volume
- The urinary system maintains fluid homeostasis in the body, regulates blood pressure, controls red blood cell production, and maintains proper pH of the blood
Synapses
- Definition: a junction between a nerve and a muscle or two nerves where impulses are transmitted by the help of a neurotransmitter
- Types of synapses: • Electrical synapses: transmit impulses through channels in the presynaptic and postsynaptic membrane, use sodium ions to transmit an electrical signal • Chemical synapses: transmit impulses through the release of neurotransmitters, types: axodendritic, axosomatic, axoaxonic, dendrodendritic, and dendrosomatic
pH Changes in the Digestive System
- In the mouth, the pH is slightly acidic to neutral (pH 6.5-7.5) due to the presence of saliva and enzymes like amylase, which initiate the breakdown of carbohydrates.
- In the stomach, the pH is very acidic (pH 1.5-3.5) due to the secretion of hydrochloric acid (HCl), which denatures proteins, activates pepsinogen, and kills pathogens.
- In the small intestine, the pH is slightly acidic to slightly alkaline (pH 6-7.4) due to the neutralization of acidic chyme by bicarbonate ions secreted by the pancreas, allowing for the proper functioning of digestive enzymes.
Mechanism of pH Maintenance in the Forestomachs of Ruminants
- In ruminants (e.g., cows, sheep, and goats), the forestomachs (rumen, reticulum, and omasum) have specific mechanisms to maintain an optimal pH for microbial fermentation.
- The rumen has an optimal pH range of 6.2-7.2, maintained through buffering agents in saliva, absorption of volatile fatty acids (VFAs), and regular motility.
- Reticulum and omasum have similar buffering and mixing mechanisms to maintain a stable pH.
Inhibition Processes in the Nervous System
- Inhibition is a reversible change in the excitability of a nerve cell, decreasing its functional activity.
- Types of inhibition: presynaptic (indirect) and postsynaptic (direct), by localization; and hyperpolarization (and strong depolarization), by the nature of the process.
- Presynaptic inhibition occurs when an inhibitory synaptic knob releases a neurotransmitter that inhibits the release of an excitatory neurotransmitter.
- Postsynaptic inhibition occurs when an inhibitory neurotransmitter connects with a postsynaptic receptor, causing hyperpolarization (inhibitory postsynaptic potential, or IPSP).
Stages of Gas Exchange in the Body
- Stage I: External Respiration or Lung Ventilation: the process of breathing (inhalation and exhalation), which occurs in the respiratory organs, including the nose, pharynx, larynx, trachea, bronchi, and bronchioles.
- Stage II: Gas Exchange and Transport: the exchange of oxygen and carbon dioxide between the lungs and bloodstream.
- Stage III: Internal or Tissue Respiration: the exchange of oxygen and carbon dioxide between the bloodstream and body cells.
Physiological Maturity
- Depends on animal species, breed, feeding and housing conditions, heredity, and animal sex
- Occurs before breeding maturity
- Females: follicles develop in ovaries, eggs mature, and first estrus cycle starts
- Males: spermatozoa form in testicles, mature in epididymis, and are discharged during sexual arousal
- Breeding maturity: body has matured, reached ≈ 70-80% of adult body weight
Functions of Water in the Body
- Forms the major part of body fluids
- Acts as a solvent and medium for enzymatic reactions
- Helps in thermoregulation
- Component of digestive juices and takes part in digestive processes
- Moisturizes air in the respiratory tract and mucous membranes
- Acts as a lubricant for joints and shock absorber for organs
Selectively Permeable Biological Membrane
- Determines the unequal distribution of ions inside and outside the cell
- Selectively receives substances important for life support and plasticity
- Permeability depends on substance size, solubility, charge, and molecular properties
Humoral Regulation of Water and Salt Metabolism
- Antidiuretic hormone (vasopressin) from neurohypophysis: intensifies water reabsorption from nephron tubules
- Aldosterone from adrenal gland cortex: intensifies Na reabsorption from nephron tubules
- Epinephrine (adrenalin) from adrenal gland medulla: narrows blood vessels of nephron tubules
Biological Effects of Testosterone
- Produced in and secreted from Leydig cells outside seminiferous tubules
- Increases muscle mass, bone mass, and sex drive
- Develops male secondary sex characteristics
- Influences behavioral effects, such as aggression and territorial marking
Link between Respiratory and Cardiovascular Systems
- Respiratory system influences venous return to the heart (respiratory pump)
- Pulmonary circulation: all blood leaving the right ventricle must pass through the lungs
- Both systems participate in the regulation of acid-base balance
- The renin-angiotensin-aldosterone system involves the respiratory system in blood pressure regulation
Liver Functions
- Bile production and fat absorption
- Excretory function (cholesterol, bilirubin) and detoxification
- Participates in blood clotting, hematopoiesis, and thermoregulation
- Synthesizes hormone precursors and inactivates hormones
- Participates in carbohydrate, protein, and lipid metabolism
Characteristics of Myocardium
- Works continuously
- Automaticity: can depolarize spontaneously without external stimulus
- Different parts of the conduction system have varying self-excitation abilities (gradient of automaticity)
- Sinuatrial node: 70-80 imp/min
- Atrioventricular node: 40-60 imp/min
- Purkinje fibers: 15-30 imp/min
- Muscle fibers are short, branched, and bound to meshwork
- All myocardial cells have the same excitability
- Not under voluntary control
Properties of Cardiac Muscle
- Conductivity: able to conduct excitation
- Contractility: able to contract, with force depending on blood supply and distension
- Excitability: able to respond to stimuli, changing with phases of the cardiac cycle
Cardiac Cycle Phases
- Absolute Refractory Period (ARP): unable to respond to stimuli during systole and 1/3 of diastole
- Effective Refractory Period (ERP): ARP plus short segment of phase 3
- Relative Refractory Period (RRP): middle of diastole, myocardium relaxes and responds to strong stimuli
- Supernormal Phase (SNP): end of diastole, excitability increases, and weaker stimuli can trigger an action potential
Action Potential Phases
- Phase 0: Depolarization, rapid Na+ influx
- Phase 1: Early repolarization, K+ efflux
- Phase 2: Plateau phase, Ca2+ influx balanced by K+ efflux
- Phase 3: Repolarization, Ca2+ channels close, and K+ channels remain open
- Phase 4: Resting phase, K+ channels keep transmembrane potential stable
Digestion
- Mechanical food processing: crushing, dissolving, mixing with digestive juices, and movement through the digestive tract
- Chemical food processing: enzymes break down polymers into monomers
- Proteases: proteins to amino acids
- Lipases: fats to glycerin and fatty acids
- Amylases: carbohydrates to monosaccharides
- Biological food processing: microflora and microfauna break down cellulose, carbohydrates, and nitrogen compounds
Insulin and Glucagon
- Insulin: lowers glucose level in blood, produced by β cells in pancreas
- Actions:
- Stimulates glycogen production in skeletal muscles
- Activates lipoprotein lipase in adipose tissues
- Activates hexokinase, glycogen synthesis, and glucose to fatty acid transformation in liver cells
- Actions:
- Glucagon: raises glucose level in blood, produced by α cells in pancreas
- Actions:
- Stimulates glycogenolysis and gluconeogenesis in liver
- Increases glucose release from liver
- Acts on adipose tissue cells to provide substrate for gluconeogenesis
- Actions:
Smooth Muscle
- Not under voluntary control
- Two types:
- Visceral (single-unit) smooth muscle:
- Found in hollow and tubular organs
- Can respond to humoral irritants
- Rhythmicity and gap junctions allow for coordinated contraction
- Multi-unit smooth muscle:
- Found in irises, lungs, hair follicles, and large arteries
- Does not react to humoral irritants
- Each fiber requires its own electrical impulse
- Visceral (single-unit) smooth muscle:
Glucocorticoids
- Short-term effects: similar to the sympathetic nervous system
- Increases heart rate, dilates pupils, boosts metabolism, and more
- Long-term effects:
- Alarm stage: sympathoadrenal system activates, producing epinephrine and ACTH
- Resistance stage: body resists harmful factors
- Exhaustion stage: body's ability to produce ACTH and glucocorticoids is depleted, leading to illness
Thirst
- A sensation of dryness in the mouth and throat associated with a desire for liquids
- Regulation mechanism:
- Central thirst center in the hypothalamus
- Stimulation by increased osmoconcentration and angiotensin II
- Neural and humoral regulation of water and salt metabolism
Skeletal Muscle Functions
- Ensuring movements (dynamic and static)
- Control of body posture
- Support
- Heat production
- Defense function
Transport of CO2
- CO2 is transported in three forms: dissolved CO2, bicarbonate ions, and carbaminohemoglobin
- CO2 combines with Hb to form carbaminohemoglobin
- Carbonic acid dissociates into hydrogen ions and bicarbonate ions
- Bicarbonate ions diffuse out of RBCs and chloride ions diffuse in (chloride shift)
- Hydrogen ions combine with Hb, promoting O2 release
Digestive Tract Functions
- The digestive tract has five main functions:
- Secretory function: glands secrete digestive juices
- Motor function: performs mechanical processing of food
- Absorption function: allows water and broken nutrients to enter the bloodstream and lymph
- Excretory function: releases substances or metabolites not used by the body
- Incretory function: hormones produced by endocrine cells enter the bloodstream
- Receptor function: receptors in the digestive tract induce various functions
Action Potential
- Action potential is a reversible change in polarization of the cell membrane
- Stages of action potential:
- Depolarization: rapid rise in membrane potential, opening of Na+ channels
- Repolarization: decrease in membrane potential, closing of Na+ channels
- Hyperpolarization: change in potential that makes the membrane more polarized
- Absolute refractory period: period of time when the cell is incapable of repeating an action
- Relative refractory period: period of time when the cell is partially capable of repeating an action
Growth Hormone (GH)
- GH, also known as somatotropin, promotes growth, metabolism, and bodily development
- Physiological roles of GH:
- Promoting growth in children and adolescents
- Regulating metabolism
- Promoting tissue repair and regeneration
- Maintaining organ function and size
- Modulating the immune system
- Potential anti-aging effects
Carbohydrate Metabolism
- Meaning of carbohydrates:
- Energy source
- Cell component (glycoproteins)
- Needed for muscle contractions and relaxation
- Needed for the action of the myocardium and nervous system
- Liver's role in carbohydrate metabolism:
- Processes most of the glucose
- Stores glycogen
- Converts glucose to lipids
- Glycogen:
- Polysaccharide stored in the liver and muscles
- Synthesized from glucose, glycerin, fatty acids, amino acids, and volatile fatty acids
- Benefits of storing glucose as glycogen: large molecule, insoluble, compact, and easily broken down
Carbohydrate Metabolism in Ruminants
- Herbivores convert most carbohydrates to volatile fatty acids (VFAs) in the forestomachs
- Ruminants use VFAs as an energy source; blood glucose is used in lower amounts
- Glucose is mainly broken down to VFAs, which are absorbed through the forestomach walls
- The level of glucose in the blood is lower in ruminants compared to other animals and humans
Inspiration
- Normal inspiration occurs by contraction of the respiratory muscles
- Diaphragm contractions decrease pressure in the pleural cavity, causing the lungs to expand
- Air is sucked into the lungs until the pressure in the lungs and external environment becomes equal
- Self-regulation of inspiration:
- Stretch receptors in the lungs do not send impulses to the respiratory center
- Inspiratory neurons are activated, sending impulses to the spinal cord and respiratory muscles
Osmotic Pressure
- Osmotic pressure is the pressure that develops due to a concentration gradient of dissolved salts across a biological membrane
- Physiological roles of osmotic pressure:
- Maintaining cell volume
- Regulating fluid balance
- Kidney function and urine concentration
- Nutrient and waste exchange
- Gastrointestinal absorption
- Production of bodily fluids
- Maintenance of blood pressure
Cardiac Cycle
- Changes in pressure in the heart chambers and nearby blood vessels during the cardiac cycle:
- Ventricular systole: highest pressure in the left ventricle and aorta
- Total diastole: pressure drops sharply in the left ventricle, but remains high in the aorta
- Right side pressure pump: reaches a maximum of 25 mm Hg in the right ventricle and pulmonary artery
Muscle Fatigue
- Muscle fatigue is a temporary decrease in muscle work capacity that disappears during rest.
- It is indicated by a decrease in the amplitude of muscle contraction.
- In the nerve/muscle preparation, the nerve gets tired first due to the depletion of resources (neurotransmitter, energy, etc.).
- Muscle fatigue occurs only in the 2nd stage, due to the decrease of energy resources (ATP) in the muscle, accumulation of metabolic end products (lactic acid, etc.), and changes in the distribution of ions in the cell.
- A muscle can stop contracting when it runs out of ATP and becomes fatigued.
Anaerobic Glycolysis
- It is a chemical process that renews ATP from glycogen (glucose) in an anaerobic way (without oxygen).
- This energy system produces 2 molecules of ATP and 2 molecules of pyruvic acid, which can be used in aerobic respiration or converted to lactic acid.
- Lactic acid is generated in muscles, causing fatigue and soreness, especially during strenuous exercise when oxygen cannot be sufficiently delivered to muscle.
Estrogen
- Estrogen hormones stimulate the growth and development of female gonads, genital organs, and female-specific secondary sex characteristics.
- They promote the proliferation of the uterine mucosa, thickening, and gland development.
- Estrogens have an important role in the estrus cycle and inhibit the development of atherosclerosis in blood vessels.
- They stimulate the growth and development of mammary glands, especially during puberty, pregnancy, and lactation.
- Estrogen prepares genitalia for copulation and transportation of spermatozoa, creates favorable conditions for fetal development, and triggers the onset of parturition.
Physiological Effects of Estrogen
- Estrogen stimulates follicular growth, participates in the regulation of LH and FSH release, and initiates sexual receptivity.
- It prepares the genitalia for copulation and transportation of spermatozoa, and creates favorable conditions for fetal development.
- Estrogen contributes to the growth and development of mammary glands and triggers the onset of parturition.
- It promotes the development of secondary sex characteristics, including skeletal features, body hair, and voice.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Questions 1-35