Anatomy and Physiology: Kidney Function and Acid-Base Balance Analysis

This assignment delves into the intricacies of kidney function, exploring its vital role in maintaining the body's fluid balance, filtering blood, and removing waste. It addresses key concepts such as glomerular autoregulation, electrolyte balance, and the processes involved in filtration. The assignment also examines tubular deamination's contribution to acid-base balance, the impact of aging on reproductive processes, and the prevalence of acidosis. Furthermore, it investigates the consequences of lacking juxtamedullary nephrons and the negative feedback mechanisms of inhibin in spermatogenesis. The assignment touches upon the role of ADH and aldosterone in fluid regulation, the implications of chronic renal failure, and the function of buffer systems. Overall, this assignment provides a comprehensive overview of kidney function and its significance in maintaining overall health and homeostasis.

Running head: ANATOMY AND PHYSIOLOGY
QUESTION AND ANSWERS
Name of the Student
Name of the University
Author Note

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Table of Contents
Answer 1....................................................................................................................................2
Answer 2....................................................................................................................................2
Answer 3....................................................................................................................................2
Answer 4....................................................................................................................................2
Answer 5....................................................................................................................................2
Answer 6....................................................................................................................................2
Answer 7....................................................................................................................................2
Answer 8....................................................................................................................................2
Answer 9....................................................................................................................................3
Answer 10..................................................................................................................................3
Answer 11..................................................................................................................................3
Answer 12..................................................................................................................................4
Answer 14..................................................................................................................................4
Answer 16..................................................................................................................................4
Answer 18..................................................................................................................................5
Bibliography...............................................................................................................................7

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Answer 1
The main job of the kidney is to filter blood and remove waste materials from the
body. Thus, it can be said that kidneys help in the maintenance of the body fluid balance.
Kidneys also maintain the homeostasis of the human body and excess salt, minerals, and
water are adjusted in the kidneys. This is the main reason or need for kidneys in the human
body.
Answer 2
During the process of filtration, blood has been found to enter the afferent arteriole
that flows inside glomerulus. Blood components including water and nitrogenous wastes
move inside glomerulus and non-filterable components are excreted by the efferent arterioles.
Autoregulation by glomerulus is achieved by maintenance of pressure differences in between
Bowman's capsule and glomerulus of the renal membrane. This rate is regulated
independently of mean arterial pressure.
Answer 3
The body has been found to monitor sodium and potassium levels in order to
determine its electrolyte balance. Sodium has been most commonly found inside the fluid
outside the body cells which helps the body to regulate the amount of body water. Potassium
is mainly found inside the body cells.
Answer 4
Dehydration has been found to occur when salt and water loss occurs more than the
intake level. The hypovolemic shock has been stated to occur when there is a fluid loss from
the extracellular region. However, after the compensation, fluid and electrolyte are again
balanced and the body restores its normal functioning,
Answer 5
Deamination is the process of amino groups' removal from the solution that passes
through the renal tubules. Acid-base balance is maintained by the removal of excess acidic of
basic amino group conjugates from the renal fluid in order to maintain homeostasis. In this
way, tubular deamination helps in the maintenance of body acid-base balance.
Answer 6
With aging, the chances of aneuploidy have been found to increase with age. This
condition has been further stated to give rise to trisomy. Since the number of reproductive
gametes decreases with age (a feature of oogenesis), steep birth defects have been found to be
associated with this feature.
Answer 7
Acidosis has been stated to occur more in human beings than alkalosis because the
human stomach is acidic in nature which can leak into the blood in case of stomach
malfunctioning. Acidosis has been found to occur when blood pH decreases from 7.35 due to
excess acid concentration.
Answer 8
The person will suffer from low levels of glomerular filtration rates (GFR) and will
release unfiltered urine with an imbalance in ion concentration. Fluid electrolyte balance will
not be maintained with an improper juxtaglomerular nephron functioning.

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Answer 9
Dimeric inhibitin B has been found to rise twice at the developmental stages which
reflect two Sertoli cell proliferation stages in puberty and infancy. Thus, it can be stated that
an inverse relationship is maintained between inhibitin and FSH during mid-puberty which
indicates the development of negative feedback inhibition.
Answer 10
This is because of the fact that glucose is excreted as a counter ion for urea and
creatinine which is absent in the dialysis fluid.
Answer 11
Countercurrent multiplication in kidneys has been found to generate osmotic gradient
using energy to reabsorb water from the tubular fluid which produces concentrated urine.
This process has been found to prevent the high amount of dilute urine each day and is the
main reason for not drinking water in a continuous pattern.
Kidneys have been found to contain two nephron types including superficial cortical
nephron and juxtamedullary nephron. Nephrons are present in each section of the glomerular
capsule with different structures and functions. The tubes are glomerulus, the proximal
tubule, the loop of Henle, the distal tube and the collecting duct. This loop of Henle has been
identified as a hairpin structure that comprises the thin descending limb, a thin ascending
limb, and a thick ascending limb. Juxtamedullary nephrons have been found to go deep inside
the inner medulla. The composition of fluid leaving the ascending loop of the loop of Henle
and enter the distal convoluted tubule where the composition is adjusted and finally drained
inside the collecting tubules. Vasa recta have been found to support this functioning
mechanism of the loop of Henle which slows the rate of blood flow and helps in the
maintenance of osmotic gradient that is required for the absorption of water.
Fig 1: Kidney nephron
Source: Webster et al. (2017)

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The thin descending limb has been found to be permeable to water and small solutes
including urea and sodium chloride. Active reabsorption of solutes from the ascending loop
of Henle has been found to increase the concentration of solutes unless they are moved down
to the descending tubule. Thus, it can be stated that this tubular fluid is hyperosmotic and
more concentrated in nature.
The thin ascending limb has been found to be passively permeable to small molecules
and impermeable to water. Thus, water has been found to be retained in this tube and the
solution becomes hyposmotic.
On the other hand, the thick ascending limb actively absorbs all sodium, chloride, and
potassium from the solution and is also impermeable to water. This segment has also been
found to be impermeable to water which prevents the escape from this loop. This tube is also
known as the diluting segment.
Multiplication of the countercurrent mechanism has been found to move sodium
chloride from the interstitial space which is located deep inside the kidneys. With fluid flow,
urine has been found to produce as soon as the new tubular fluid enters the descending limb.
Loop diuretics are medicines that increase the flow of urine and work by the inhibition of
sodium-potassium chloride cotransporter that is located inside the loop of Henle. This process
leads to an increased loss of the ions and excess water is drawn into the nephron to increase
the volume of urine in the tubes. This is the overall function of loop diuretics associated with
kidney functioning.
Answer 12
Metabolic acidosis has been found as the specific acid-base problem, most common in
the human population. Metabolic acidosis has been found to occur due to an increased acid
production which occurs due to diabetic ketoacidosis. Initial blood pH has been found to be
low for the patient's blood. The primary signs of metabolic acidosis have been observed as
rapid and shallow breathing, fatigue, increased heart rate, jaundice, headache, and sleepiness.
Acute metabolic acidosis has been found to last from a few minutes to several days.
Sometimes it has been found to cause severe illnesses leading to patient hospitalizations. This
process has been found to be caused when the human body produces excess organic acid
amounts including lactic or keto acids. Compensated metabolic acidosis has been found to be
involved in a decrease in the partial pressure of CO2 which becomes 1.2 mmHg for every 1.0
mEq/L decrease in the value. This disorder is caused by the accumulation of acid due to
increased acid production and the indigestion of acid. Anion gap has been found to be the
highest during ketoacidosis including chronic kidney disease and lactic acidosis. In this way,
acute metabolic acidosis has been found to be differentiated from compensated metabolic
acidosis. The renal compensation of metabolic acidosis has been found to work with acidosis
by releasing acidic urine. The renal excretion of H+ ion has been found to enhance as the
renal function of aluminum production has been found to be induced by glutamine. The
factor called the renal response to metabolic acidosis has been found to be mediated by an
increased gene expression associated with enzyme encoding ability. The enzymes encoded
include ion transporters and glutamine catabolism which contributes to the synthesis and
excretion of NH3 ions along with the net production. This is the overall renal compensation
of the disorder termed as metabolic acidosis. Respiratory compensation has also been found
to be calculated mathematically by the procedure just discussed prior to the last section. By
anion gap, one is able to understand the amount of blood that can be used to show whether
blood has an electrolyte imbalance or not. A high anion gap has been found to be associated

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with metabolic acidosis which is characterized by high amounts of acidic ion concentrations.
Thus, it can be stated that secondary metabolic acidosis can be tested by the anion gap.
Answer 14
ADH has been observed to act by increasing the absorption of H2O inside the distal
convoluted tubule or the DCT. Aldosterone, on the other hand, has been found to increase
sodium reabsorption inside the DCT and the collection duct of the kidney nephrons. In a
more convenient way, it can be said that both these compounds work together to maintain the
fluid balance inside the tubules Antidiuretic hormone or ADH has been found to order
kidneys to hold water back and aldosterone couples it with the reabsorption of sodium also.
This is because of the fact that water ions follow sodium ions in their direction associated
with the concentration gradient. Aldosterone is the most significant mineralocorticoid
hormone that is released by the adrenal gland (zona glomerulosa). This hormone has been
found to play a pivotal role in the maintenance of fluid and electrolyte balance. An increase
in the levels of aldosterone has been found to induced sodium retention followed by a
potassium loss. Mineralocorticoids are hormones that are secreted by the adrenal cortex to
help in the regulation of water and salt balance inside the body. Aldosterone secretion has
been found to be triggered as soon as the blood sodium levels decrease to give rise to low
blood pressure. On the other hand, antidiuretic hormone, or ADH has been found to regulate
the amount of water that is excreted from kidneys. This hormone helps in the reabsorption of
blood to capillaries in lowering the blood osmolarity back to the normal value. ADH has also
been found to control the water reabsorbed from the tubules and collecting ducts inside the
kidney. This compound retains water, causes a constriction in arterioles and peripheral
circulation which affects some social behaviors of the organisms also. During chronic renal
failure, the inability to excrete fluid from the body will lead to fluid building up inside the
blood vessels which can cause pulmonary edema. During chronic renal failure, it has been
observed that patients have a tendency to develop hyperkalemia, hypervolemia and
bicarbonate deficiency. Thus, it can be stated that the fluid balance is disturbed due to excess
retention of sodium. However, the fluid can appear normal due to a dilution because of fluid
retention. Renin retention will further lead to the transformation of angiotensinogen to
angiotensin I in response to low blood pressure. Renin retention will destroy the system of
RAS (renin-angiotensin system) and blood pressure including fluid and electrolyte balance
will be disturbed. This function can lead to an increase in the volume of extracellular fluid in
the blood.
Answer 16
In short, it can be stated that the buffer systems help in the proper functioning of
blood plasma including phosphates, bicarbonates and plasma proteins. The kidneys have been
found to control the acid-base balance by the excretion of hydrogen ions and finally
generating bicarbonate which acts as a buffer and helps in the maintenance of blood plasma
pH inside a normal range.
Taking the example of blood buffer, the system consists of H2CO3 and bicarbonate
anion which is required to maintain blood pH between the values of 7.35 to 7.45. A higher or
lower value has often been found to cause death among the patients. According to various
observations, it has been found that in the first equilibrium system, carbonic acid and water
has been found to be in equilibrium. The reaction has been given below-
H3O+ + HCO3- gives H2CO3 + H2O

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In the human body, another equilibrium between oxygen and hydronium has been
found to involve the binding ability of hemoglobin. As soon as the hydronium ion increases,
it has been found that the equilibrium shifts to the oxygen side which releases oxygen and
vice versa for a decrease in hydronium ion concentration in blood. The simultaneous
equilibrium following the previous one is-
H2CO3 gives H2O+CO2
Hydrochloric acid is not a buffer because it is only a strong acid and the combination
of two solutes is required to make a buffer solution. Since HCl is not a weak acid, thus the
combination of the two solutes will never form a buffer solution. The main property of the
buffer is that it never changes its concentration of pH with the additives. HCl completely
dissociates in water and aqueous solution. Thus, HCl cannot be used as a buffer solution.
Thus, it can be stated that for this reason, buffers are important for blood and its pH. The
average value of pH for human urine is 6.0. This value is maintained by the buffer system of
urine which is maintained by the kidneys. The hydrogen ion is released into the urine and
absorption of bicarbonate in blood plasma has been also found. Sodium and bicarbonate have
also been found to be balanced. Sodium and bicarbonate have been found to be always
balanced by the same buffer system as of blood. An equal quantity of bicarbonate added to
the blood has been found to be associated with acid excretion in the form of urine. The pH of
the urine has been found to be increased with the increase of protein content in the body and
decrease of the carbohydrate content. This is caused when the equilibrium of the buffer
reaction shifts towards the left which turns the pH of urine to an acidic state. A large volume
of urine with low pH is excreted which minimizes the risk of uric acid stone formation during
starvation. The same mechanism is followed for decreasing the pH value of urine.
Answer 18
Gametogenesis has been defined as the process in which diploid precursor cells have
found to undergo meiotic division to give rise to haploid gametes or sex cells.
In males, spermatogenesis is the name given to this process which leads to the
production of sperm- Spermatozoa
In females, oogenesis has been given as the name to the process to produce eggs or
ova. Gametogenesis has been found to have similar characteristics in males and females in
terms of multiple mitotic divisions and growth of precursor germ cells, the fusion of two
meiotic cells to produce one daughter cell which is haploid in nature and the differentiation of
one daughter haploid cells to produce functional gametes.
Spermatogenesis has been found to begin at puberty when the epithelium of the
germline associated with seminiferous tubules has been found to divide by mitosis. These
cells grow to form spermatocytes which undergo two meiotic divisions to give rise to haploid
daughter cells (spermatids) and finally differentiated into spermatozoa. On the other hand,
oogenesis has been found to being during fetal development which increases the number of
primordial cells by mitosis. The number of functional cells produced by spermatogenesis is
four and oogenesis cells do not divide equally, 3 polar bodies and only one gamete are
formed. The cells formed from spermatogenesis are equal in size and contain equal amounts
of cytoplasm. Oogenesis daughter cells retain all the cytoplasm and a single size is
maintained. One sperm is produced continuously whereas one egg is released every month
from puberty during the menstrual cycle.
The primary onset of puberty in males is controlled by two hormones: FSH or the
follicle-stimulating hormone initiates the process of spermatogenesis and LH or lutein signals

7ANATOMY AND PHYSIOLOGY
the release of testosterone. FSH is essential for causing the Sertoli cells in the testes to begin
spermatogenesis. Leydig cells of testes are triggered by LH to produce testosterone which
causes the development of male characteristics. As the levels of testosterone and
spermatogenesis increase, the Sertoli cells start releasing inhibitin to stop the release of LH
and FSH from the master gland (pituitary gland). Dimeric inhibitin B has been found to rise
twice at the developmental stages which reflect two Sertoli cell proliferation stages in puberty
and infancy. Thus, it can be stated that an inverse relationship is maintained between inhibitin
and FSH during mid-puberty which indicates the development of negative feedback
inhibition. This is the overall function of FSH and LH in the male reproductive system.

8ANATOMY AND PHYSIOLOGY
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