Digestion/Nutrition/Kidneys Flashcards

Question

Defication reflex

Answer 1

Positive feedback loop Arrival of fecal matter causes activation of ***stretch receptors*** Activation of stretch receptors causes ***Parasympathetic Activation*** Parasympathetic activation causes both ***Distension & Contraction*** Which activates ***Stretch receptors***, which activates ***Contraction & Parasympathetic Activation***

Answer 2

chemical reactions that occur in the body occuring in cell majority of reactions are occuring in either the cytocell or mitochondria \*necessary to maintain life & homeostasis

Answer 3

Anabolism and catabolism create a circular series of expectations within the cell drawing from nutrient pool of AA's, Lipids, Sugars/carbohydrates Anabolism - **creates** stored reserves from nutrient pool for maintenance and repair Prioities for building 1. Amino Acids 2. Lipids 3. Sugars/Carbohydrates Catabolism - draws from storage for repair and maintenance and production of energy Priorities for breakdown 1. Sugars/Carbohydrates 2. Lipids 3. Amino Acids

Answer 4

60% of energy is lost to heat in mitochondria 40% is used in production of ATP ATP is used in body for transport, locomotion, construction, endo/exocytosis, cytokensis

Answer 5

Areobic Metabolism - O2 is required vs Anerobic Metabolism - happens all the time; is able to continue in the absence of O2; it does not require O2 to function ***\*\*The whole point of carbohydrate metabolism is breaking down glucose to make ATP***

Answer 6

C₆H₁₂O₆ ⇒ Heat, 6CO₂ + 6H₂O, ATP Three functions of glucose occur in the cytosol and mitochondria of all cells except RBC's (RBC's only do glycolosis, because RBC's transport Oxygen and therefore it cannot use it as well, making system inefficent) * Glycolosis * Krebs Cycle (Citric Acid Cycle, Tricarbonic Acid Cycle) * Oxidative Phosphorylation (electron transport chain, electron transport system) glucose ⇒ ATP \*if glucose is not avaliable we can use fatty acids, glycerol, or AA's

Answer 7

* ***_Breakdown of glucose into pyruvic acid_*** * ***_Occurs in the cytosol_*** * ***_problem with glycolosis is it is not fast enough to keep up with the demand for ATP_*** ***\*\*all we really need to know\*\**** coenzymes - organic molecules needed to catalyze enzymatic reactions (sometimes vitamins or minerals) * NAD⁺ « H * FAD⁺ « H (Hydrogens are added in the process) C-C-C-C-C-C 6 Carbon chain (**passes into cell via facillitated diffusion/carrier mediated diffusion (ie. insulin**) P-C-C-C-C-C-C Phosphate attached upon entering cell (glucose 6 phosphate) - because it is no longer just glucose, we've maintained concentration gradient outside the cell (this way there will always be a higer concentration of glucose out side the cell)) Another Phosphate attaches P-C-C-C-C-C-C-P Then splits into two 3 carbon chains where another phosphate is attached to each P-C-C-C-P P-C-C-C-P The two phosphates are donated to two ADP molecules per chain to make 4 ATP molecules Three Carbon chains are known as Pyruvic acid ⇒ used in Krebs Cycle \*\*If pyruvic acid accumulates it becomes Lactic Acid

Answer 8

Primary function of Krebs cycle is to remove H atoms from organic molecules and transfer them to coenzymes (NAD, FAD) to be used in Electron Transport Chain Key Points * CO2 released * Hydrogens are borrowed for use in ETC * a small amount of ATP is made * Aceytl-CoA is the starting point which is used with other organic molecules instead of glucose * occurs in the mitochondria NAD++ and FAD++ carry donated electrons for use in electron transport chain

Answer 9

can separate Hydrogen ions which can cause acidosis \*Patient who become septic because they have some sort of infection, they have fever, now they poor circulation which will not allow for continuation of Kreb's cycle leading to accumulation of Pyruvic acid then Lactic acid which will then circulate causing acidosis causing an increase in breathing (hospitals will draw lactate level to determine whether PT is septic or not) \*\*Rhabdomyolysis - is a condition in which damaged skeletal muscle tissue breaks down quickly; sloughing off of skin, or ruptured blisters; anytime there are cells that are rupturing there is a release of K (party in the cells K) into the blood stream, causing secondary effects

Answer 10

* is a series of protein complexes embeded in the mitochondrial membrane * electrons captured from donor molecules in Krebs cycle are transfered through these complexes * coupled with this transfer is the pumping of hydrogen ions * this pumping generates the gradient used to synthesize ATP = ***chemosmosis*** \*\*Create H+ = gradient then uses gradient for the synthesis of ATP

Answer 11

* ETC and Kreb's Cycle occur in the mitochondria * Glycolosis occurs in the cytosol

Answer 12

1. Triglycerides can be broken down into fatty acids and glycerol * 3 fatty acids ⇒ Aceytl CoA * glycerol (can be converted to) ⇒ pyruvic acid (can be brought into Kreb's cycle or through backward conversion, made into glucose) ⇒ Acetyl CoA 2. Glycogen ⇒ glucose ⇒ pyruvic acid (can be brought into Kreb's cycle or through backward conversion, made into glucose) ⇒ Acetyl CoA 3. Proteins ⇒ Amino acids * ⇒ Acetyl CoA * ⇒ pyruvic acid (can be brought into Kreb's cycle or through backward conversion, made into glucose) ⇒ Acetyl CoA * ⇒ can be brought directly to Kreb's cycle

Answer 13

ie ***gluconeogenisis*** - synthesis of glucose from non-carbohydrate precursors * lactic acid * pyruvate * A.A.'s * glycerol \*once glucose is made we can make glycogen ≈ glycogenesis \*glucose can only be made in certain cells - ie liver & kidney

Answer 14

Triglycerides are one of the most abundant kind of lipids Lipolysis - breakdown of lipids Breakdown of lipids for the sake of making Energy in form of ATP * Triglycerides are broken down into 3 fatty acids and 1 glycerol * glycerol ⇒ pyruvic acid ⇒ into mitochondria for use with Aceytl CoA or in Kreb's cycle * fatty acid brought into mitochondria via ***Beta Oxidation*** to make acytic acid chains (C-C) which can be used in Kreb's cycle ⇒ 144 ATP from 1 18 Carbon Fatty Acid (1 glucose molecule = 32-36 ATP) * Byproduct is Ketone Bodies or Ketone Acids

Answer 15

Ketone Bodies/Ketones ≈ Ketones are acids which will release H+ into the bloodstream causing shift in pH ⇒ CO2

Answer 16

Fatty Acids + glycerol = Triglycerides * Fatty acids obtained from either diet or from Acytel CoA * Glycerol obtainied from intermediates from glycolosis

Answer 17

High-density lipoprotein (HDL) is one of the five major groups of lipoproteins, which, in order of sizes, largest to smallest, are chylomicrons VLDL IDL LDL HDL - densest because of ratio of lipid/protein which enable lipids like cholesterol and triglycerides to be transported within the water-based bloodstream. In healthy individuals, about thirty percent of blood cholesterol is carried by HDL Low density Lipo- Proteins can be transported to peripherial tissues which in transport it has the opportunity to clog arteries and get stuck, causing circulatory problems High density Lipo-proteins are transported from the peripherial tissues to the liver. **Because of the direction of transport they are not as bad**

Answer 18

* can be metabolized after broken down into amino acids * directly into the krebs cycle * brought into mitochondria to be used with Aceytl CoA * or converted into pyruvic acid and then into Aceytl CoA * ***Transamination*** (or aminotransfer) is a chemical reaction between two molecules. One is an amino acid, which contains an amine (NH2) group. The other is a keto acid, which contains a keto (=O) group. In transamination, the NH2 group on one molecule is exchanged with the =O group on the other molecule. The amino acid becomes a keto acid, and the keto acid becomes an amino acid. * ***Deamination*** - removes amino group from amino acid ⇒ amino group is converted to **amonia** then to **urea** by the liver (hepatic encephalopathy - toxic amonia levels in blood stream due to liver failure - Lactulose is medicine that aids in binding amonia for excretion) * Remainder of amino acid can then be: * converted to Pyruvic acid (final product of glycolosis/precursor to TCA cycle) or use that for glyconeogenesis (making new glucose from non carbohydrate precursors). * Converted into Aceytl CoA * Converted into Keytone Bodies

Answer 19

As Baby 10 essential AA's (essential in the diet) 8 can be synthesized in the body 20 Total AA's As Adult 8essential AA's (essential in the diet) 12 can be synthesized in the body

Answer 20

***Minerals*** - inorganic ions - electrolytes salts ie.sodium, potassium, chloride, calcium, Many functions: NeuroTransmitter release, blood clotting, action potential, buffer systems, **\*****Function as cofactors for enzymatic reactions** **(ie presence of minerals in Krebs cyle to enable cyle to continue)** ***Vitamins*** - essential in the diet, organic nutrients, organically similar to lipids and carbohydrates which can be: * fat (ADEK) soluble - stored for a long time ie. never are going to run out of them * or water soluble ( not likely to OD on them, but can develop a toxicity(all others ie B, C, Vitamin H is biotin (synthesis of fatty acids and role in Krebs, B1 Thiamine, B2 Riboflabin, B3 Niacin, B5 pantothenate aka. **Aceytl CoA**, Muric acid - Vitamin D)

Answer 21

* Suggested to drink 40ml/kg of water daily * As you increase your body temperature by 1 degree celcius than you are going to lose an extra 200ml of water * if you increase your metabolic demand you will lose water * if you increase demands, you must increase intake

Answer 22

How organinsms use and aquire energy usually measured in **Calories** **cal** = Calorie is the amount of energy required to raise the temperature of 1g of water by 1 degree celcius **kcal or Cal** = 1000 smaller calories Lipids ≈ 9 cal/g Carbs/Proteins ≈ 4 cal/g Ethanol ≈ 7 cal/g **metabolic rate** = sum of anabolic and catabolic reactions that are occuring in body at time of measurment **Basal Metabolic Rate = ** calculated by height and weight at rest

Answer 23

How body mantains homeostasis with regards to temperature Mechanisms of heat transfer: **Radiation** - Transfer of heat in form of infrared radiation **Conduction -** physical transfer of heat **Convection** - Transfer of heat due to movement of molecules around an object **Evaporation -** change of liquid to vapor **Respiration -** nose warms air, breathing exchanges warm air with the environment * **insensible respiration** - unrealized loss of heat to the environment ie the epithelium and the lungs * **sensible respiration** - sensible, something you can feel ie sweating

Answer 24

* largely responsible for heat regulation; function is to control fluctuations and keep it stable * Heat loss center - parasympathetic; when we want to lose heat on purpose * Heat gain center - sympathetic, to increase in body temperature

Answer 25

* Vasodilation - widens blood vessels up and brings blood closer to skin to allow **radiation & Convection** to help bring temperature back down * Sweating - heat loss via **evaporation** * Increase in respiratory rate - more heat from lungs can be lost

Answer 26

\*goal = get more heat into body * **vasoconstriction** & **shunting**- tighten bloodvessels down and bring them closer into the body, giving them less opportunity to lose heat with the environment; bring most of blood to the core where it can be kept warm * **Thermogenesis (Shivering)** - ie shivering creates heat by violent contraction of skeletal muscles. * **Dispersion of Hormones (Non-shivering) - ** hormonal stimulation of metabolic rate ie Epi and Thyroxnine

Answer 27

Principal structures & responsibilities Kidneys - making urine Ureters - tranfer of urine to bladder via peristalsis Bladder - stores urine can expand via transitional epithelium Urethra - expulsion of urine - In/external Sphincters

Answer 28

**Excretion** - elimination of stuff we don't want **Elimination -** physical process of getting it out of body **Homeostatic Regulation ** - regulating BP, Blood volume, Acid-Base Balance, water balance Regulating that every thing is in the blood in the right concentration or is eliminated accordingly Some function in terms of detoxification and preservation of nutrients

Answer 29

Top of the kidney is at top of 11th and 12 ribs and remainder is exposed set retroperitonal in thoracic cavity T12-L3 about the size of a fist

Answer 30

Direct branch coming off of both the Aorta and IVC for each kidney (**Renal Artery and Renal Vein**) **Hillum -** entrance to the kidney (ie Hillus for lungs) **Nerves** - **Ureter** - exit for urine from kidneys **Adrenal Glands** sit ontop of each kidney - triangle shaped Outer linings (covering) **Adipose Capsule** - fat tissue for cushioning from blows **Renal Fascia** - Stabilization of the structure **Renal Capsule** - Stabilization of the structure

Answer 31

**Cortex -** overall internal structure **Medulla -** aka pyramid **Renal Pelvis -** dumping basin for urine before it gets moved to ureter **Nephrons** straddle cortex and medula

Answer 32

**Afferent arteriole** (larger) Enters Bowman's Capsule, where the Glomerus (capillary network is housed), it exits as the **Efferent Arteriole** and becomes the **peritubular capillaries** which surround the proximal and distal tubules the **Vasa Recta -** are straight capillaries that lie parallel to the loop of Henele. \* There are approximatley 2 Million nephrons in the kidneys

Answer 33

**Renal corpuscle** is the initial blood-filtering component of a nephron. It consists of two structures: a glomerulus and a Bowman's capsule. Remainder is called **Renal Tubules** **Proximal Convoluted Tubule (PCT)** **Loop of Henele** - Decending/Ascending Limb **Distal Convoluted Tubule** (DCT) **Collecting duct**

Answer 34

a **juxtamedullary** nephron is one where the renal corpuscle is close to the medulla, and the proximal convoluted tubule and its associated loop of Henle occur at a deep position compared to most other nephrons.

Answer 35

The tubules are a single layer thick. Objects must be able to pass through the single cell, or go around, ie inbetween the cells.

Answer 36

Toxins & Waste Products - kind of big However we have little stuff that we want to keep

Answer 37

**Filtration** - happens in Glomerulus due to hydrostatic pressure exceeding osmotic pressure. It filters out: * ***water, salt, glucose, amino acids, and waste products (urea, uric acid, creatitnine)***; * *we won't lose plasma proteins (such as hemoglobin and albumin)* (negatively charged particals wil pass less frequently than positively charged particles) **Reabsorbtion** **(into blood vessel out of nephron - ie reabsorbed into the body)** - mostly happens in PCT and Loop of Henele **Secretion (into nephron out of blood vessel - ie excretion from body**)- mostly happens in the DCT \*Both reabsorbtion happen in both places based on the type of cell that is surrounding that particular tube, better at certain functions than others

Answer 38

Once fluid comes out of Bowman's capsule it is called **Filtrate.** Once fluid passes into Proximal Tubule ie is called **Tubular Fluid** Once fluid passes through collecting duct it is called **Urine.**

Answer 39

Urea Creatnine Uric Acid

Answer 40

Ions: Ca, Cl, Na, K Glucose, Amino Acids Via **Reabsorption** = back into the body, ie saving it in the blood vessel & **Secretion** = Excretion from body \*Both can be active and passively transported **Plasma Proteins** are too big to leave capillaries which is important because they will help draw back in some of the fluid/stuff we want to keep later

Answer 41

Glomerulus - Afferent enters/Efferent exits **Fenestrated Capilary** - holes or slits in capillaries, **Podocytes** exert some control over what is released from capillary. PCT - Hormone PTH - Ca2+ reabsorbtion 95% of nutrient reabsorbtion & 80% of water reabsorbtion in the loop of Henele **Decending limb** of the loop of Henele is permeable only to water **Ascending Limb** - Permeable only to salt, concentration of salt wants to leave due to gradient on ascending \*\*Because of this permeability - concentration gradients work to our advantage **Counter current multiplier allows for continuious reabsorption of water** **and salt**

Answer 42

Phenomenon in the loop of henele that happens because: Decending limb of the loop of Henele is permeable only to **water** Ascending Limb - Permeable only to **salt**, concentration of salt wants to leave due to gradient on ascending ***\*\*Because of this permeability - concentration gradients work to our advantage*** ***Counter current multiplier allows for continuious reabsorption of water and salt***

Answer 43

to filter out stuff we don't want in the blood and get back things that we lost during filtration process

Answer 44

When Blood glucose reaches **180mg/dL**, the body cannot physically reabsorb any more glucose, there is an increased loss in glucose causing an increase in water loss. \*\*glucose given in form of Manitol in hospital setting to draw water out of brain cells, the same way hypertonic saline would, and functions as a diuretic to rid excess water

Answer 45

* Water * Sodium * Ca2+ * Cl- * AA's * glucose * salts \*\*PCT responsible for most of reabsorbtion * **PTH (parathyroid hormone) is going to promote Ca2+ reabsorption**; the absence of PTH promotes additional excretion

Answer 46

* Water reabsorbed in descending limb * Na reabsorbed in Ascending limb \*\*Counter current multiplier - * as we lose water from descending limb, because it is permiable to water and nothing else * as we move to the ascending limb the salt concentration is now higher realitive to the amount of water * The salt will now naturally want to fallout of the loop of henele and into the extracellular space * Because there is now more salt in the extracellular space, water in descending limb will want to move out, causing a continuous circuit of reabsorbtion (positive feedback, more loss of water=greater loss of Na=more loss of water etc)

Answer 47

* More secretion takes place in DCT than reabsorption * Primary place for K+ reabsorbtion * Active secretion of: H+, or Bicarb ions * if you want to get rid of them on purpose in the Urine * if we wanted to save more Na we can excrete K or excrete H+ on purpose, * Can be regulated with the use of hormones - ie. **Aldosterone will cause increased Na reabsorption** in exchange for secretion of K or hydrogen ion * (the absence of Aldosterone promotes additional excretion) \*\*The other half of maintaining Acid-Base balance along with respiration \*Respiratory system is responsible for the minute to minute changes by converting it to carbonic acid then converted to CO2 which can be expelled via respiration.

Answer 48

Urine in the collecting duct flows into the renal pelvis, which feeds into the ureter * In the presence of ADH, aquaporins form to collect water and prevent dieresis. * The absence of ADH promotes excretion

Answer 49

* approximatley **125ml/min** * volume lost to filtration every minute * 99% reabsorbed * indicates efficency of the nephron \*if we have a disruption in bloodflow then it will disrupt the GFR; the bodys interest is to maintain this rate at all costs unless the patient becomes severley hypotensive. \*\* if drops \<80 Systolic; blood flow from nephron goes away completely which leads to kidney failure (approx 2 hours without blood flow) \*\*\*Body protects in order (4-6min Heart, Lungs, 10 min Brain, 2hrs Kidneys)

Answer 50

* Glucose = means bgl is \> 180mL/dL * bilirubin = breakdown of Heme of aging RBC's * urobilin = breakdown of Heme of aging RBC's * ketones = production of glucose from lipids and Amino Acids * specific gravity = concentration vs diluted (higher the specific gravity the more concentrated it is) * pH - 4.8-8 range - how much H+ is excreted * blood - looked for in trauma * proteins - indicates a problem with filtration * nitrates - indicate UTI; presence of bacteria * leukocytes - indicate UTI; presence of bacteria

Answer 51

* Local * Neural * Hormonal

Answer 52

Reactions to minor changes in BP * Minor Drop in BP * ***vasodilation*** - of the afferent arteriole (increasing the amount of blood flow arriving) * ***vasoconstriction*** of the efferent arteriole (increases hydrostatic pressure and maintains filtration) * Minor increase in BP * **Stretch** causes **Vasoconstriction** of Afferent arteriole limiting the amount of blood arrival into the glomerulus for filtration

Answer 53

* any **Sympathetic** activation causes **vasoconstriction** of afferent arteriole * results in decrease in availability of blood; usually as a result as a significant drop in blood pressure (\<80systolic) = kidney failure if prolonged

Answer 54

special collection of cells that makes contact with the ascending limb of the loop of Henele, Bowmans capsule and the Afferent arteriole Contains: * **Mechanical receptors** that control SMC in Afferent Arteriole in response to increase in BP * **Chemoreceptors** at the Ascending limb of the loop of Henele for reabsorption of NaCl * Produces **Renin** enzyme necessary for conversion of Angiotensinogen and activation of *Renin-Angiotensin System* is activated.

Answer 55

* is a hormone system that regulates blood pressure and water (fluid) balance * Angiotensinogen converted to Angiotensin I by enzyme renin * Angiotensin I is converted to Angiotensin II via ACE (Angiotensin Converting Enzyme) * Angiotension II is the active hormone that can cause various effects (see Angiotensin II Flashcard) * Angiotensin II also stimulates the secretion of the hormone aldosterone from the adrenal cortex \*If the renin–angiotensin–aldosterone system is abnormally active, blood pressure will be too high. There are many drugs that interrupt different steps in this system to lower blood pressure. These drugs are one of the main ways to control high blood pressure (hypertension), heart failure, kidney failure, and harmful effects of diabetes.

Answer 56

* Peripherial Vasoconstriction increases BP systemically, helping to perfuse vital organs * Constriction of **Efferent** Arteriole - increases amt of bloodflow to the glomerulus to maintain Glomerular Filtration Rate * Release of ADH - keeps more water * Release of Aldosterone/E/NE - keeps more Na ⇒ keeps more water; E/NE promote peripherial vasoconstriction

Answer 57

* opposes Renin-Angiotensin System * released by cardiac muscle cells in response to Increased BP/Blood Volume * Decreases reabsorption of Na+ ⇒ increase in Na excreted * dilation of glomerular capillaries ⇒ increases filtration ⇒ water loss * ***inhibits*** production of **renin/aldosterone/ADH**

Answer 58

From **Renal Pelvis** (inside Kidneys) urine is moved via peristalsis throught the **Ureter ** (approx 12" long) passes into pelvic cavity to the **Bladder** where it is stored until expelled **Slits** in posterior wall of the bladder allows urine in but does not allow backflow **Bladder** consists of 3 layers of muscle called ***Detrusior Muscle*** which is responsible via contraction for the expulsion of urine **Urethra** is guarded by an ***internal** (involuntary*) and ***external*** *(voluntary) **sphincter*** - there must be coordination between voluntary and involuntary muscles for urine to be expelled. Urethra length: 1" in females; 7-8" in males. Top of Urethra is guarded by the **prostate**; an *enlarged prostate will press on the urethra and make it harder for urine to be expelled* ⇒ urine retention

Answer 59

From in-to-out * Layer of *transitional epithelium* (similar to rugae in stomach which allows for expansion) * *Longitudinal Muscle Layer -* similar to intestine * *Circular Muscle Layer* - similar to intestine * *Connective tissue * which is continuious with the **Renal Capsule** (outer surface of the Kidneys

Answer 60

1. **200ml** urine in bladder sends sensory signal via ***Parasympathetic NS*** 2. Conscious awareness that bladder is full = need to urinate 3. Contraction of **Detrusior** muscle by ***parasympathetic stimulation*** 4. relaxation of **external uretheral sphincter** is followed by relaxation of **internal** **uretheral** **sphincter** = urination If conscious relaxation of *external uretheral sphincter* does not occcur, detrusior muscles relax, process begins again in **1 Hour** \*\***Capacity of bladder is 1 Liter**

Answer 61

Glucose is caustic to the veins Chronically high levels of High bgl = increase in excretion of glucose leading to damage in filtration process Damage casuse fenestrations to enlarge, allowing proteins to pass trough and eventually nothing we want to filter is being filtered leading to need for dialysis to facilitate filtration of blood

Digestion/Nutrition/Kidneys Flashcards

(85 cards)