Structure and Function of Systems Flashcards
What are the four types of tissues?
- Epithelial
- Connective (bone, cartilage, blood)
- Muscle
- Nervous
Bringing conditions back to their normal homeostatic function
negative feedback
The volume of air that is normal inhaled or exhaled in one breath
tidal volume
control of exchange of heat with the environment
thermoregulation
These organisms obtain heat from the environment
Cold-blooded/Ectotherm/Poikilotherm
These organisms generate their own body heat and have a higher basal metabolic rate than their counterparts
Warm-blooded/Endotherm/Homeotherm
The maximum volume of air that can be inhaled after a normal tidal volume inhalation
Inspiratory reserve volume (IRV)
The left lung contains ___ lobes. The right lung contains ___ lobes.
2
3
Why is the left lung smaller?
to accommodate the heart
The volume of air that can be inhaled after a normal exhalation;
VT + IRV
Inspiratory capacity (IC)
Lines the inside of the chest cavity
parietal pleura
Has negative pressure relative to the atmosphere, if stabbed, air rushes in and causes lungs to collapse
Intrapleural space
What happens to the lungs as we inhale and exhale?
Inhale: volume increases, diaphragm contracts, pressure decreases
Exhale: volume decreases, diaphragm relaxes, pressure increases
Where gas exchange occurs between the circulatory system and lungs
alveoli
What is surfactant?
A detergent like complex, reduces surface tension and helps keep the alveoli from collapsing.
Filters, moistens, and warms incoming air. Mucus secreted by goblet cells traps large dust particles here
Nose
Throat, passageway for food and air; dust and mucus are swept back here by cilia for disposal via spitting or swallowing
Pharynx
The volume of air remaining in the lungs after a normal exhalation
ERV + RV
Functional residual capacity (FRC)
Epiglottis covers this
Trachea
What is the order of the respiratory system?
Mouth & nose, pharynx, trachea, epiglottis, bronchi, bronchial tubes, bronchioles, alveoli, circulatory system.
What is the Bohr effect?
The shift in the oxygen dissociation curve caused by changes in concentration of CO2 or pH.
Curve shifts right = needs more O2 “CADET, face right!”
High CO2
Acidic
High 2,43 DPG
Exercise
High Temperature
Opposite when curve shifts left
What is the Haldane effect?
deoxygenation of blood increases its ability to carry CO2
-Increase in Co2 pressure, there is increase CO2 blood concentration. However, when hemoglobin is saturated with oxygen, its capability to hold CO2 is reduced
Oxygen diffuses from
Alveoli into the blood
CO2 diffuses from
blood into the lungs
Majority of CO2 in the blood is in the form of
Bicarbonate (70%)
23% bound to Hemoglobin
7% dissolves in plasma
How is respiration controlled?
Medulla oblongata
- partial pressure of CO2 increases causing increase rate of ventilation
- Diaphragm contracts
- Lungs inflate, pressure decreases, volume increases
Both central (medulla) and peripheral (heart) chemoreceptors
Pathology marked by destruction of alveoli
Emphysema
what is respiratory acidosis?
Results from inadequate ventilation; we don’t clear enough CO2 and it builds up, so more H+ is formed, lower the pH
What is respiratory alkalosis?
Results from breathing too rapidly (hyperventilation); we are losing CO2 too quickly so H+ and HCO3- start combining to form more CO2 and pH starts rising
An increase in H+ or CO2 will cause a (increase/decrease) in breathing rate. High blood O2 partial pressure would cause a (increase/decrease) in breathing rate.
Increase
Decrease
What is the equation for cardiac output?
stroke volume x heart rate
SV = volume of blood discharged from ventricles with each contraction
CO = volume discharged from the ventricle each minute
What is the equation for blood pressure or mean arterial pressure?
CO x Systemic Vascular Resistance
CO = cardiac output
SVR = resistance controlled by vasoconstriction/dilation - the larger the diameter, the less resistance
The maximum volume of air that can be exhaled after a normal tidal volume exhalation
Expiratory reserve volume (ERV)
The amount of air remaining in the lungs after maximum exhalation; air that cannot be exhaled
Residual Volume (RV)
The maximum volume of air that can be exhaled after a maximum inspiration;
IRV + VT + ERV
Vital capacity (VC)
The maximum amount of air that the lungs can accommodate
IC + FRC
Total lung capacity
What is the path of blood?
Vena cava, right atria, tricuspid, right ventricle, PSLV, pulmonary artery, lungs, pulmonary vein, left atria, bicuspid/mitral, left ventricle, ASLV, aorta, body
What is the path of circulation?
Away from heart
aorta –> arteries –> arterioles –> capillaries
Toward heart
capillaries –> venules –> veins
What is the ejection fraction?
stroke volume/end diastolic volume
blood that leaves the ventricles when heart pumped
What is the electrical conduction of the heart?
- SA Node - pacemaker - sends impulse to contract the atria
- AV Node - sends impulse to ventricles
- Bundle of His (AV Bundle) - impulses passes through here
- Purkinje Fibers - impulses arrives here and causes ventricles to contract
What are chordae tendinae and papillary muscles?
Chordae tendinae are small cordlike structures that connect the AV valves to the walls of the heart and work with the papillary muscles located in the walls of the ventricles to make a tight seal to prevent backflow when ventricles contract.
Why are ventricle walls thicker?
Because they pump blood to the body and lungs and atria only have to pump blood to fill ventricles
Why is the left side of the heart thicker than the right?
Left ventricle pumps blood to most of body
Right ventricle pumps blood to lungs
What is systole?
contraction of atria and ventricles
What is diastole?
relaxation of atria and ventricles
Compare and contrast veins, capillaries, and arteries.
Transports interstitial fluid
lymphatic system
True or false: Blood is a connective tissue
True
What are the components of blood?
- Plasma (55%) - aqueous mixture of nutrients, salts, gases, wastes, hormones, and blood proteins
- Blood serum - same as plasma minus clotting factor components
Cellular Components (45%)
3. Erythrocytes (RBC) - Red blood cells - transport oxygen on hemoglobin
4. Leukocytes (WBC) - White blood cells - involved in infection
5. Platelets - involved in clotting
What is the process of blood clotting?
- Formation of platelet plug
- Release of thromboplastin
- Conversion of prothrombin to thrombin
- Conversion of fibrinogen to fibrin
- Clot formation
What stimulates a babies first breath?
CO2 and temperature change from womb to outside
What is the pathway of fetal circulation?
Oxygenated, nutrient-rich blood from placenta
carried to fetus via umbilical vein —> half of
the blood enters the ductus venosus, which
allows blood to bypass the liver —> blood is
carried to the inferior vena cava —> right
atrium —> right ventricle —> ductus arteriosus
(conducts some blood from the pulmonary
artery to the aorta [bypassing the lungs/fetal
pulmonary circulation]) —> aorta
The other half of the blood that didn’t enter the
ductus venosus enters the live/portal vein —>
right atrium —> foramen ovale (a small opening
in the heart which allows blood to bypass
pulmonary circulation by entering the left atrium
directly from the right atrium since there is no
gas exchange in the fetal lung) —> left atrium —
> left ventricle —> aorta
What is the equation for stroke volume?
end diastolic volume - end systolic volume
EDV = volume of blood in ventricle just before contraction
ESV = blood in the ventricle at the end of contraction/systole
What are the four ways humans excrete wastes
- Lungs - CO2 and H2O diffuse from blood and are continually exhaled
- Liver - processes nitrogenous wastes, blood pigment wastes, other chemicals, and produces urea
- Skin - sweat glands in the skin excrete water and dissolved salts to regulate body temperature
- Kidney - excretes wastes via the following pathway:
kidney –> ureter –> bladder –> urethra
What is the nephron composed of? Label it.
- Renal Corpuscle
- Glomerulus
- Bowmans Capsule - Renal Tubule
- Proximal Convoluted Tubule
- Loop of Henle (Descending loop, Ascending loop)
- Distal Convoluted Tubule
- Collecting Duct
What are the four steps in urine formation?
- Filtration
- filtrate becomes filtered through the glomerulus (afferent arteriole –> glomerulus –> efferent arteriole) and is then pushed into the Bowmann’s capsule via hydrostatic pressure of blood
- proteins and large particles (blood cells) that are can’t filter remain in the circulatory system - Reabsorption
- glucose, salts, amino acids are reabsorbed from filtrate and return to the blood in the proximal convoluted tubule via active transport
- NaCl and bicarbonate are actively reabsorbed in the distal convoluted tubule via active transport
- water passively flows - Secretion
- acids, bases, ammonia, drugs, and ions are secreted by both passive and active transport from the peritubular capillaries and into the nephron - Concentration
- ADH prevents water loss by making the collecting duct more permeable to water
- when BP is low, aldosterone increases reabsorption of Na+ by the DCT and collecting duct, which increases water retention
What is the function of the loop of henle?
What is the path of urea through the collecting duct?
- Urea first descends to the medulla (salty party) where ADH/vasopression can make more water leave from urine by increasing permeability of the collecting duct (via increased aquaporins) –> urine is even more concentrated
- Aldosterone can act on collecting duct by increase Na+ reabsorption, resulting in water passively following Na+
- By the time urine emerges, it usually has varying amounts of H2O, urea, NaCl, K+ and creatinine
If alcohol blocks the creation of vasopressin what does this mean for urine output?
More urine output since H2O is reabsorbed by the body
Area where food and air passages cross; epiglottis, a flap of tissue that blocks the trachea so only solid and liquid enter, is located here
Pharynx
What is the juxtaglomerular apparatus?
- Contains macula densa which monitors filtrate pressure in DCT
- If BP low: granular cells secrete renin –> angiotensin cascade –> adrenal cortex to synthesize aldosterone –> more H2O absorbed from DCT and blood pressure rises and is restored to normal
The osmolarity gradient in the kidneys is creating by entering and exiting of solutes, and (increases/decreases) from the cortex to the medulla.
Increases
The descending loop is permeable to _____. The ascending loop is permeable to ______. This is known as the _______.
water (so less salty)
salts and ions (more salty)
counter current multiplier
Takes place within cells and food is phagocytized and fuses with food vacuoles. Lysosomes break down nutrients.
What organisms does this occur in?
Intracellular digestion
Amoeba, Paramecium, Porifera
Takes place outside the cells usually in a food compartment continuous with the animal’s body
What organism does this occur in?
Extracellular digestion
Mostly everything
What is the pathway of digestion?
Mouth, pharynx (throat), esophagus, stomach, small intestine, large intestine, colon
Salivary amylase breaks down starch into maltose by breaking a-glycosidic bonds and chewing creates a bolus
Mouth
What are the 9 main functions of the liver?
- Blood storage
- Blood filtration
- Kupfer cells phagocytize bacteria - Carbohydrate Metabolism
- blood glucose levels - Fat Metabolism
- syntehsizes bile to breakdown fats - Protein Metabolism
- deaminates amino acids, forms urea from ammonia, synthesizes plasma proteins and nonessential amino acids - Detoxification
- Erythrocyte Destruction
- Kupfer cells destroy irregular erythrocytes - Vitamin Storage (A, D, B12)
- Glycogenesis and Glycogenolysis
Tube leading toward the stomach, food travels by peristalsis
Esophagus
What occurs in the stomach during digestion?
Storage - stomach folds (rugae) allow for 2-4 L of storage
Mixing - H2O, food, gastric juice mix and form chyme
Physical breakdown - muscles activated to break down food, HCl denatures proteins and kills bacteria
Chemical breakdown - pepsin digests proteins
Controlled release - chyme enters small intestine via pyloric sphincter
What are the 5 stomach cells?
- Mucous cells - secrete mucus that lubricates and protects stomach’s lining
- Chief cells - secrete pepsinogen which is activated to pepsin by low pH in stomach - protein digestion
- Parietal cells - secrete HCl, intrinsic factor assists B12 absorption
- G cells - secrete gastrin which stimulate parietal cells to secrete HCl
- ECL cells - neuroendocrine cells activated by gastrin to release histamine which stimulates parietal cells to secrete HCl
What is the pH of the stomach?
2
What are the 3 parts of the small intestine? What occurs in the small intestine during digestion?
- Duodenum - continues breakdown of starches and proteins as well as remaining food types
- Jejunum - absorption of nutrients
- Ileum - absorption of nutrients
DIGESTION
1. structure - contain villi to increase surface area for better digestion and absorption, goblet cells secrete mucus to protect from mechanical or chemical damage
- enzyme - protelytic enzymes (i.e, proteases, disaccharadidases, lipases, nucleotidades, phosphatases, and nucleosidases)
Structure connected to large intestine
ileocecal valve
90% of digestion and nutrient absorption occurs in the _____
small intestine
What occurs in the pancreas during digestion?
- Secretes bicarbonate (helps neutralize acidic chyme)
- Exocrine gland releasing enzymes from acinar cells via pancreatic duct –> duodenum
- Enzymes: trypsin, chymotrypsin, lipase, pancreatic amylase, deoxy/ribonucleases
What is the pH of the duodenum?
6
What is the function of the liver in digestion?
- produces bile to emulsify (breakdown) fats
- sodium bicarbonate neutralizes stomach acid
- small intestine absorbs breakdown products (amino acids and sugars –> capillaries, fatty acids and glycerol –> lymphatic system –> bloodstream)
- chyme moves through intestine via peristalsis
Where is bile stored?
gallbladder
The valve controlling release of bile and pancreatic juice into the small intestine
Sphincter of oddi
What occurs in the large intestine during digestion?
- water and electrolyte absorption
- feces stored at end of large intestine in the rectum and excreted through the anus
- bacteria (like e. coli) a symbiont in large intestine = main source of vitamin K (also produce b12, thiamin, riboflavin)
How long is the small intestine?
6 meters
How long is the large intestine?
1.5 meters
What are the 4 hormones involved in digestion?
- Gastrin - produced by stomach lining when food reaches
- Secretin - produced by cells lining duodenum in response to HCl to stimulate bicarbonate production
- Cholecystokinin - secreted by small intestine in response to fat digestases - stimulates galbladder to release bile and pancreas to release enzymes
- Gastric Inhibitory Peptide - produced in response to fat/protein digestases in duodenum; effect = mild decrease of stomach motor activity
What are the 5 hormones involved in hunger?
- Grehlin - via stomach wall, initiates hunger
- Leptin - via adipose tissue, inhibits hunger
- Peptite YY - via small intestine, hunger and lack of hunger
- Insulin - via pancreas, stores glucose as glycogen in liver
- epinephrine - suppresses hunger
Phagocytes of CNS
microglia
Label the neuron
Neuron - consists of dentrites, an axon, and a cell body
Axon hillock - where the soma (cell body) connects to thte axon; action potentials generated here
Dendrites - receive information and transfer it to the cell body
Axon - transfers impulses away from cell body
Myelin sheath - insulates axon and separations are called nodes of ranvier; involved in saltatory conduction
Produce myelin in the central nervous system
oligodendrocytes
Produce myelin in the peripheral nervous system
Schwann cells
Describe an action potential
- Resting potential = -70 mV
- Action potential = Na+ channels open, Na+ comes in, if -50 mV reached then an action potential will occur
- Repolarization = in response to Na+ flow, K+ flows out of cell, restoring polarization (Na + are now inside, K+ is now out)
- Hyperpolarization = by the time channels close, too much K+ is released (~ - 80 mV)
- Refractory period - neuron will not respond to a new stimulus
- Absolute refractory period = Na+ channels inactivated, nothing can cause an action potential
- Relative refractory period = a large stimulus can create an action potential
*prevents an action potential from moving backwards
Use cilia to circulate cerebrospinal fluid
ependymal cells
groups of cell bodies in the PNS that serve as support cells
satellite cells
provide physical support to neurons of the CNS and maintain mineral and nutrient balance
astrocytes
What are the three types of neurons?
- Sensory - receives initial stimulus from brain
- Motor - travel from the brain and stimulate target cells (i.e., muscles, sweat glands, etc)
- Interneuron - receive impulses from sensory neurons and sends impulses to motor neurons