Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Human Phys ch. 19
| Question | Answer |
|---|---|
| urine, | the fluid waste produced by the kidneys, reflects the functioning of the body |
| ureter | A smooth muscle tube connecting the bladder with the kidney |
| The bladder expands and fills with urine until, in a reflex called micturition or urination, the bladder contracts and expels urine through a single tube, the | urethra |
| A cross section through a kidney shows that the interior is arranged in two layers: an | outer cortex, and inner medulla. |
| The layers, cortex and medulla, are formed by the organized arrangement of microscopic tubules called | Nephrons. |
| What is the functional unit of the kideny? | The nephron |
| In the Renal portal system, blood flows from renal arteries into an afferent arteriole. From the afferent arteriole it goes into the first capillary bed, a ball-like network known as | the glomerulus. |
| What are the three basic processes that occur in the nephron? | Filtration, reabsorption, and excretion |
| Filtration | the movement of fluid from blood into the lumen of the nephron. Filtration takes place only in the renal corpuscle, where the walls of glomcrular capillaries and Bowman’s capsule are modified to allow bulk flow of fluid |
| Filtrate | Filtered fluid, once it passes into the lumen of the nephron, it becomes part of the body’s external environment, |
| anything that filters into the nephron is destined for | Excretion, removal in the urine, unless it is reabsorbed in the body. |
| After filtrate leaves Bowman’s capsule, it is | modified by reabsorption and secretion. |
| Reabsorption is the process of | moving substances in the filtrate from the lumen of the tubule back into the blood flowing through peritubular capillaries. |
| Secretion | selectively removes molecules from the blood and adds them to the filtrate in the tubule lumen. |
| The volume of fluid that filters into Bowman’s capsule per unit time is the | glomerular filtration rate (GFR). |
| Average GFR is | 125 mL/min, or 180 L/day |
| What are the four main functions of the Kidneys? | Filtration, reabsorption, filtration, and excretion |
| What is the order in which filtrate travels through a nephron? | Bowman's Capsule, Proximal tubule, Loop of Henle, Distal Tubule, Collecting duct |
| Anything that enters the nephron is destined for what? | secretion |
| what is the filtrate that flows into the Bowman's capsule identical to? | The plasma, and nearly isosmotic |
| What happens in the Bowman's Capsule? | Filtration from the glomerulus into the nephron |
| What happens in the proximal tube? | Isosmotic reabsorption of organic molecules, ions and water, as well as the secretion of xenobiotic materials and metabolites. |
| What is the primary function of the proximal tube? | The isosmotic reabsorption of solutes and water |
| Of the different parts of the nephron, which is the primary site for the creation of dilute urine? | The loop of henle |
| What is reabsorbed most in the loop of Henle? | Solutes |
| The reabsorption of water and solutes from the tubule lumen to the extracellular fluid depends on | active transport |
| Water leaves the tubule with solutes by | osmosis |
| What is the primary driving force for most renal reabsorption? | The reabsorption of Na+ |
| What is the equation for the amount secreted? | Amount filtered - amount reabsorbed + amount secreted |
| Reabsorption occurs when | proximal tubule cells transport solutes out of the lumen, and water follows by osmosi |
| Sodium-linked secondary active transport in the nephron is responsible for the reabsorption of | many substances, including glucose, amino acids, ions, and various organic metabolites |
| On the basolateral side of the cell, Na+ is pumped out by | the Na+@K+@ATPase, while glucose diffuses out with the aid of a facilitated diffusion GLUT transporter. |
| The nitrogenous waste product urea has | no active transporters in the proximal tubule but can move through the epithelial junctions by diffusion if there is a urea concentration gradient. |
| When Na+ and other solutes are reabsorbed from the proximal tubule, the transfer of osmotically active particles makes the extracellular fluid more | concentrated than the filtrate remaining in the lumen |
| In response to the osmotic gradient, water moves | by osmosis across the epithelium. Up to this point, no urea molecules have moved out of the lumen because there has been no urea concentration gradient. |
| When water is reabsorbed, the concentration of urea in the lumen | increases—the same amount of urea is contained in a smaller volume. Once a concentration gradient for urea exists, urea moves out of the lumen. |
| Saturation refers to | the maximum rate of transport that occurs when all available carriers are occupied by (are saturated with) substrate |
| At substrate concentrations below the saturation point, transport rate is directly related to | substrate concentration |
| At substrate concentrations equal to or above the saturation point, transport occurs at a | maximum rate. The transport rate at saturation is the transport maximum |
| In diabetus Militus, glucose is | filtered faster than the carriers can reabsorb it. The carriers become saturated and are unable to reabsorb all the glucose that flows through the tubule. As a result, some glucose escapes reabsorption and is excreted in the urine. |
| What is the formula for glucose excreted? | Glucose excreted = glucose filtered - glucose reabsorbed |
| Under normal conditions, all filtered glucose is | reabsorbed. In other words, filtration is equal to reabsorption. |
Created by:
jacquixg