Question

How can urine contain a higher concentration of waste than the blood

A How can urine contain a higher concentration of win the verton) than the the A Urine mot since the process is elve diffusion B Reabsorption of water in the loop of the nephron and collecting ducts leaves behind a more concentrated urine. C. All stages in the kidney involve active transport . Une can be hypertonic for small moleculesidit is v on for an equal number of molecules E. The whole nephron is impermeable to water. Uningen i stedet 44. Na+ is always reabsorbed in the but is only reabsorbed in the hormonal influence A) descending limb of nephron loop, distal convoluted tubule B) ascending limb of nephron loop, distal convoluted tubule C) ascending limb of nephron loops proximal convoluted tubule D) descending limb of nephron loop, ascending timb of nephron loop 45. Nerve impulses from sympathetic neurons causing Ay decrease, constriction of afferent glomerular arterioles B) decrease; constriction of efferent glomerular arterioles C) increase; dilation of afferent glomerular arterioles D) increase; dilation of efferent glomerular arterioles glomerular filtration rate by Increase dilation of affer efferent glomerular arterial of efferent glomerular arteriarterioles 46. In the process of tubular secretion, the A) nutrients: blood; tubular fluid B) nutrients; tubular fluid, blood C) unwanted substances; blood; tubular fluid D) unwanted substances; tubular fluid; blood are moved from the 47. During reabsorption in the proximal convoluted tubule, most of the amino acids. glucose, Nations, K+ ions, and Ca2+ ions are removed from the tubular fluid by mechanisms. A) passive transport B) counter transport C) osmotic D) active transport 48. decreases the glomerular filtration rate. A) Aldosterone B) The sympathetic nervous system C) Antidiuretic hormone D) Angiotensin II

Answers pls

Bio 102

Answer 1

43. B

The nephrons are the functional units of kidney. A nephron consists of an outer cortex and an inner medulla. An afferent arteriole brings blood which is to be filtered and the efferent arteriole takes back filtered blood.

A nephron consists of -

Bowman's capsule

Glomeruli

Proximal Convoluted tubule (PCT)

Loop of henle -- ascending and descending loop

Distal convoluted tubule (DCT)

Collecting duct

3 process, namely, filtration, absorption and secretion occur which concentrate the urine.

Filtration occurs in the glomeruli while the other two occur in all other parts of the nephron.

Mainly, the PCT allows reabsorption of all essential nutrients, electrolytes, water. H⁺, NH³, K⁺ are secreted here from blood while HCO^3- is reabsorbed.

Loop of hwlw is important in maintaining high osmolarity. The descending limb is penetrable to water but not to ions while the ascending limb is impenetrable to water but allows exchange of ions.

DCT allows regulated reabsorption of water and Na⁺, while secretng K⁺, NH₃, HCO^3- is also reabsorbed.

Collecting duct reabsorbs a large amount of water so as to produce a hypertonic urine.

44. B

45. A

46. C