Pancreas Questions in English

(D) The correct answer is $D$. Heterocrine glands,also known as mixed glands,possess both exocrine components (with ducts) and endocrine components (ductless).
Examples include the pancreas and gonads (testes and ovaries).
$1$. Exocrine part secretes enzymes into ducts.
$2$. Endocrine part secretes hormones directly into the blood.

(D) The endocrine part of the pancreas is known as the islets of Langerhans.
It contains $4$ types of cells: $\alpha$-cells (alpha cells),$\beta$-cells (beta cells),$\delta$-cells (delta cells),and $PP$-cells (or $F$-cells).
Therefore,the correct answer is $4$.

(B) The pancreas is a mixed gland (heterocrine gland).
Its exocrine part,consisting of acinar cells,secretes pancreatic juice containing enzymes.
Its endocrine part,consisting of the Islets of Langerhans,secretes hormones like insulin and glucagon.
Therefore,pancreatic juice and hormones are secreted by different cells.

(A) The Islets of Langerhans are specialized clusters of endocrine cells found within the pancreas.
These clusters are responsible for the production and secretion of hormones such as insulin and glucagon,which play a crucial role in regulating blood glucose levels.
Therefore,the correct answer is the pancreas.

(C) The correct matching is as follows:
$1$. Beta cells $(A)$ are found in the Islets of Langerhans in the pancreas and secrete insulin $(r)$.
$2$. Mast cells $(B)$ are connective tissue cells that release histamine $(q)$ during inflammatory responses.
$3$. Paneth cells $(C)$ are found in the crypts of Lieberkühn in the small intestine and secrete lysozyme $(p)$,which has antibacterial properties.
$4$. Acinar cells $(D)$ are the exocrine cells of the pancreas that secrete pancreatic enzymes $(s)$.
Therefore,the correct combination is $A-r, B-q, C-p, D-s$.

(B) Glucagon is a peptide hormone secreted by the $\alpha$-cells of the Islets of Langerhans in the pancreas.
It acts mainly on the liver cells (hepatocytes) and stimulates glycogenolysis,which is the breakdown of glycogen into glucose.
This process increases the blood glucose level (hyperglycemia).
Therefore,glucagon is a hyperglycemic hormone.

(A) The Islets of Langerhans are endocrine clusters found in the pancreas. The $\beta$-cells within these islets are responsible for the production of the hormone insulin,which regulates blood glucose levels.

(C) Treatment with alloxan and streptozocin specifically destroys the beta cells of the Islets of Langerhans in the pancreas.
These beta cells are responsible for the production of insulin.
Consequently,the destruction of these cells leads to a decrease in insulin levels,resulting in a 'diabetic state' (hyperglycemia).
Therefore,the correct option is $C$.

(B) The pancreas is a glandular organ that develops from the endodermal lining of the embryonic gut (archenteron). During embryonic development,the dorsal and ventral pancreatic buds emerge from the endoderm of the duodenum,which is part of the foregut. Therefore,the correct origin of the pancreas is the endoderm.

(C) The normal blood glucose level in a healthy individual is maintained within a specific range.
When the blood sugar level rises above this normal physiological range,the condition is termed as $Hyperglycemia$.
$Glucosuria$ refers to the presence of glucose in the urine.
$Glycolysis$ is the metabolic pathway that breaks down glucose into pyruvate.
$Hypoglycemia$ refers to a condition where blood sugar levels fall below the normal range.

(B) Somatostatin is secreted by the delta cells of the Islets of Langerhans in the pancreas.
Insulin is secreted by the beta cells and glucagon is secreted by the alpha cells of the same Islets of Langerhans in the pancreas.
Therefore,the source of somatostatin is the same as that of insulin and glucagon.

(B) $Insulin$ is a peptide hormone produced by the beta cells of the pancreas.
It plays a major role in the regulation of glucose homeostasis in the blood.
$Insulin$ acts primarily on hepatocytes (liver cells),adipocytes (adipose tissue),and myocytes (muscle cells) to enhance cellular glucose uptake and utilization.
It promotes glycogenesis (conversion of glucose to glycogen) in the liver and muscles,and lipogenesis (fat storage) in adipose tissue,thereby lowering blood glucose levels.

(B) Diabetes mellitus is a metabolic disorder characterized by high blood glucose levels (hyperglycemia). It is primarily caused by a deficiency or ineffective action of the hormone insulin,which is secreted by the beta cells of the Islets of Langerhans in the pancreas. Therefore,it is classified as a hormonal deficiency.

(B) Insulin is a hormone that lowers blood glucose levels by facilitating the uptake of glucose into cells,particularly muscle and adipose tissue.
An overdose of intravenous insulin causes a rapid and severe drop in blood glucose levels,a condition known as hypoglycemia.
When blood glucose levels fall significantly,the brain,which relies heavily on glucose for energy,cannot function properly.
This can lead to loss of consciousness,seizures,coma,and eventually death if not treated immediately with glucose administration.

(B) The correct matching pair is $\alpha$ cells of pancreas - $Glucagon$.
$1$. $\alpha$ cells of the pancreas (Islets of Langerhans) secrete the hormone $Glucagon$, which increases blood glucose levels.
$2$. Thyroid gland secretes $Thyroxine$ $(T_4)$ and $Triiodothyronine$ $(T_3)$, not $Epinephrine$.
$3$. $Epinephrine$ and $Norepinephrine$ are secreted by the adrenal medulla, not the anterior pituitary.
$4$. $Secretin$ is a hormone secreted by the $Duodenal$ mucosa (small intestine), not the stomach epithelium.

(B) $Diabetes \text{ } mellitus$ is a metabolic disorder characterized by high blood glucose levels.
It is caused by the deficiency or ineffective action of the hormone insulin.
Insulin is a peptide hormone secreted by the $\beta$ cells of the Islets of Langerhans located in the pancreas.
Therefore, the correct option is $B$.

(A) The pancreas is a heterocrine (composite) gland, meaning it functions as both an exocrine and an endocrine gland.
The endocrine part of the pancreas consists of about $1$ to $2$ million groups of specialized cells known as the "Islets of Langerhans".
These islets contain various cell types, such as alpha cells (secreting glucagon) and beta cells (secreting insulin), which play a crucial role in regulating blood glucose levels.

(D) Glucagon is a hyperglycaemic or diabetogenic polypeptide hormone secreted by $\alpha$-cells of the islets of Langerhans in the pancreas.
Its primary function is to increase blood glucose levels by stimulating glycogenolysis and gluconeogenesis in the liver.
Its secretion is stimulated by low blood sugar levels (hypoglycaemia).

(D) Carbohydrate metabolism in the body is primarily regulated by the hormones secreted by the pancreas,namely $Glucagon$ and $Insulin$.
$Glucagon$ is a hyperglycemic hormone that increases blood glucose levels by stimulating glycogenolysis and gluconeogenesis.
$Insulin$ is a hypoglycemic hormone that decreases blood glucose levels by facilitating the uptake of glucose by cells and promoting glycogenesis.
Together,these two hormones maintain glucose homeostasis in the blood.

(A) Glucagon is antagonistic to insulin.
Antagonistic hormones are those which work against each other.
Glucagon increases the blood glucose level (hyperglycemic hormone),whereas insulin decreases the blood glucose level (hypoglycemic hormone).

(C) The correct answer is $C$.
Insulin is a peptide hormone.
When taken orally,insulin is broken down and digested by the proteolytic enzymes present in the stomach and small intestine before it can reach the bloodstream.
Therefore,it is ineffective when taken by mouth.
Intravenous injection of insulin allows the hormone to enter the bloodstream directly,where it facilitates the uptake of glucose by cells,thereby decreasing the blood sugar level.

(C) The correct answer is $C$. In $1921$,Frederick Banting and Charles Best successfully isolated insulin from the pancreas of a dog. They demonstrated that this extract was effective in reducing blood sugar levels in diabetic dogs,which was a landmark discovery in the treatment of diabetes.

(B) Insulin is a peptide hormone produced by the $Beta$ cells of the Islets of Langerhans in the pancreas.
These cells are responsible for regulating blood glucose levels by facilitating the uptake of glucose into cells.

(B) $Glucagon$, which is secreted by the $\alpha$-cells of the islets of $Langerhans$, stimulates the conversion of glycogen into glucose (a process known as glycogenolysis), thereby increasing blood glucose levels.

(B) Insulin is a peptide hormone produced by the $\beta$-cells of the Islets of Langerhans in the pancreas. It plays a crucial role in regulating blood glucose levels by facilitating the uptake of glucose into cells.

(D) The pancreas acts as both an exocrine and an endocrine gland.
- The exocrine part secretes pancreatic juice containing enzymes (like amylase,trypsin,lipase) and bicarbonate ions into the duodenum via the pancreatic duct.
- These secretions are responsible for the digestion of carbohydrates,proteins,and fats,as well as the neutralization of acidic chyme.
- The endocrine part (Islets of Langerhans) secretes hormones like insulin and glucagon directly into the blood to regulate blood glucose levels.
- Since the endocrine secretions do not travel through the pancreatic duct,blocking the duct will not affect the maintenance of normal blood sugar levels.
- Therefore,the correct option is $D$.

(A) The islets of $Langerhans$ are endocrine clusters found in the pancreas that secrete hormones like insulin and glucagon.
Insulin is responsible for lowering blood glucose levels by facilitating the uptake of glucose into cells.
If the islets of $Langerhans$ stop functioning,the production of insulin will decrease (short supply).
As a result,the body will be unable to regulate blood sugar,leading to a significant rise in blood glucose levels,a condition known as hyperglycemia.

(B) Alloxan is a toxic glucose analogue that selectively accumulates in the $\beta$-cells of the islets of Langerhans in the pancreas. Due to its ability to generate reactive oxygen species,it causes the destruction of these cells,which leads to a decrease in insulin production and is often used in research to induce experimental diabetes mellitus in animal models.

(A) Glucagon is a peptide hormone secreted by the $\alpha$-cells of the pancreas.
It acts mainly on the liver cells (hepatocytes) and stimulates glycogenolysis,which is the breakdown of glycogen into glucose.
This process results in an increased level of glucose in the blood (hyperglycemia).
Therefore,the secretion of glucagon leads to an increase in blood glucose levels.

(A) Insulin is a peptide hormone secreted by the $\beta$-cells of the Islets of Langerhans in the pancreas.
It plays a major role in the regulation of glucose homeostasis in the blood.
Insulin acts mainly on hepatocytes and adipocytes and enhances cellular glucose uptake and utilization.
It promotes glycogenesis,which is the process of converting excess blood glucose into glycogen for storage in the liver and muscles.
Therefore,it lowers blood glucose levels (hypoglycemic factor).

(D) Insulin is a peptide hormone synthesized as a precursor called proinsulin. Proinsulin consists of three chains ($A, B,$ and $C$). During maturation,the $C$-peptide is removed to form functional insulin,which consists of two chains ($A$ and $B$) linked by disulphide bridges. Therefore,the functional nature of insulin is $NOT$ the same as that of proinsulin,as proinsulin is biologically inactive. Options $A, B,$ and $C$ are correct facts regarding insulin structure and regulation.

(A) The pancreas acts as a heterocrine gland containing the Islets of Langerhans.
$1$. Beta $(\beta)$ cells of the pancreas are responsible for the secretion of the hormone insulin, which helps in lowering blood glucose levels.
$2$. Alpha $(\alpha)$ cells of the pancreas are responsible for the secretion of the hormone glucagon, which helps in increasing blood glucose levels.
Therefore, the respective order for beta and alpha cells is insulin and glucagon.

(D) The pancreas is a heterocrine (or composite) gland,meaning it functions as both an exocrine and an endocrine gland.
$1$. Exocrine function: It secretes digestive enzymes (such as trypsinogen,chymotrypsinogen,amylases,and lipases) into the duodenum via the pancreatic duct.
$2$. Endocrine function: It secretes hormones like insulin and glucagon from the Islets of Langerhans directly into the blood to regulate blood glucose levels.
Therefore,the correct answer is $D$.

(C) Insulin and glucagon are peptide hormones secreted by the pancreas to regulate blood glucose levels.
Insulin is secreted by the $\beta$-cells of the Islets of Langerhans and acts to lower blood glucose levels (hypoglycemic hormone).
Glucagon is secreted by the $\alpha$-cells of the Islets of Langerhans and acts to increase blood glucose levels (hyperglycemic hormone).
Since they are produced by different cells and have opposite effects on blood glucose concentration,they are considered to perform antagonistic functions.

(C) $Glucagon$ is a peptide hormone secreted by the $\alpha$-cells of the $Islets$ of $Langerhans$ in the pancreas.
It acts mainly on the liver cells $(hepatocytes)$ and stimulates glycogenolysis,which is the breakdown of glycogen into glucose.
This process increases the blood glucose level,acting as a hyperglycemic hormone.
Therefore,it helps in releasing glucose into the blood from liver cells.

(D) $Diabetes \ mellitus$ is a metabolic disorder characterized by high blood glucose levels (hyperglycemia).
It is primarily caused by the deficiency or ineffective action of the hormone $Insulin$,which is secreted by the $\beta$-cells of the $Islets \ of \ Langerhans$ in the pancreas.
$Insulin$ is essential for the uptake of glucose by cells and for maintaining blood sugar homeostasis.
Therefore,the correct option is $D$.

(D) Insulin is a peptide hormone secreted by the $\beta$-cells of the Islets of Langerhans in the pancreas.
It plays a major role in the regulation of glucose homeostasis by enhancing cellular glucose uptake and utilization.
Failure of insulin production or secretion leads to a condition known as Diabetes mellitus,characterized by prolonged hyperglycemia (high blood glucose levels) and the excretion of glucose in the urine (glycosuria).

(B) The correct answer is $B$. The pancreas is a mixed gland (heterocrine gland) because it contains both exocrine and endocrine portions.
$1$. The exocrine portion consists of acini that secrete digestive enzymes into the duodenum.
$2$. The endocrine portion consists of the Islets of Langerhans,which secrete hormones like insulin and glucagon directly into the blood.

(B) The normal concentration of glucose (sugar) in human blood is approximately $0.1\%$ (or $80-120 \text{ mg/dL}$ in a fasting state).
This level is tightly regulated by hormones like insulin and glucagon to maintain physiological homeostasis.

(B) Insulin is a peptide hormone produced by the beta cells of the pancreatic islets of Langerhans. It plays a critical role in carbohydrate metabolism by facilitating the uptake of glucose from the blood into cells,thereby lowering blood glucose levels and promoting glycogenesis (the conversion of glucose to glycogen).

(B) The Islets of Langerhans are clusters of endocrine cells found within the pancreas. They are responsible for the production and secretion of hormones such as insulin and glucagon,which regulate blood glucose levels. Since they lack ducts and release their secretions directly into the blood,they are classified as endocrine glands.

(B) The pancreas is a heterocrine (compound) gland,meaning it functions as both an exocrine and an endocrine gland.
$1$. The exocrine part consists of acini cells,which secrete pancreatic juice containing digestive enzymes into the duodenum.
$2$. The endocrine part consists of the Islets of Langerhans,which contain different types of cells (e.g.,alpha and beta cells) that secrete hormones like glucagon and insulin directly into the blood.
Since these functions are performed by distinct anatomical structures within the organ,the secretion is performed by different cells.

(D) The process of converting glucose into glycogen in the liver is known as glycogenesis.
This process is regulated by the hormone insulin,which is secreted by the beta cells of the Islets of Langerhans in the pancreas.
Insulin promotes the uptake of glucose by liver cells (hepatocytes) and stimulates its conversion into glycogen for storage.
Therefore,the pancreas is the gland responsible for this regulation.

(A) The Islets of Langerhans are specialized clusters of endocrine cells found within the pancreas. These clusters contain various cell types,such as alpha cells (which secrete glucagon) and beta cells (which secrete insulin),which play a crucial role in regulating blood glucose levels.

(A) The pancreas acts as both an exocrine and an endocrine gland.
The endocrine part of the pancreas consists of clusters of cells known as the Islets of Langerhans.
These islets contain different types of cells,including alpha $\alpha$ cells and beta $\beta$ cells.
Alpha cells secrete the hormone glucagon,while beta $\beta$ cells are responsible for the secretion of the hormone insulin.
Therefore,the correct option is $A$.

(D) The $Pancreas$ is a heterocrine or composite gland,meaning it functions as both an exocrine and an endocrine gland.
$1$. As an exocrine gland,it secretes digestive enzymes (such as trypsin,lipase,and amylase) into the duodenum via the pancreatic duct.
$2$. As an endocrine gland,it secretes hormones (such as insulin and glucagon) directly into the blood to regulate blood glucose levels.
Therefore,the correct option is $D$.

(B) The pancreas acts as both an exocrine and an endocrine gland.
Its endocrine part consists of the Islets of Langerhans,which contain different types of cells.
These cells include $\alpha$-cells (alpha cells) and $\beta$-cells (beta cells).
The $\alpha$-cells secrete the hormone glucagon,which increases blood glucose levels.
The $\beta$-cells secrete the hormone insulin,which decreases blood glucose levels.
Therefore,glucagon is secreted by the $\alpha$-cells of the Islets of Langerhans.

(C) Glucagon is a peptide hormone secreted by the $\alpha$-cells of the Islets of Langerhans in the pancreas.
It acts mainly on the liver cells (hepatocytes) and stimulates glycogenolysis,which is the breakdown of glycogen into glucose.
This process increases the blood glucose level (hyperglycemic hormone).
It also stimulates gluconeogenesis,which contributes to the increase in blood glucose levels.
Therefore,option $C$ is the correct function.

(D) Insulin is a hypoglycemic hormone secreted by the $\beta$-cells of the pancreas,which lowers blood glucose levels by facilitating the uptake of glucose into cells.
Glucagon is a hyperglycemic hormone secreted by the $\alpha$-cells of the pancreas,which increases blood glucose levels by stimulating glycogenolysis (breakdown of glycogen to glucose) in the liver.
Therefore,glucagon acts antagonistically to insulin to maintain glucose homeostasis in the blood.

(D) Glucagon is a peptide hormone produced by the alpha cells of the pancreas. It acts mainly on the liver cells (hepatocytes) and stimulates glycogenolysis (breakdown of glycogen into glucose),resulting in increased blood sugar levels (hyperglycemia). When blood glucose levels become excessively high,glucose is excreted in the urine,a condition known as glycosuria. Therefore,an excess of glucagon can lead to glycosuria.