T4. LIVER PHYSIOLOGY

Question 1

What does the small intestine receive from the stomach?

Answer 1

Chyme.

Question 2

What secretions enter the digestive tract at the junction of the stomach and small intestine?

Answer 2

Secretions from the liver and pancreas.

Question 3

Why are liver and pancreas secretions important for the small intestine?

Answer 3

They are essential for the digestive process in the small intestine.

Question 4

Where is the liver located?

Answer 4

Below the diaphragm, on the right side of the abdominal cavity, near the junction of the stomach and small intestine.

Question 5

What are the functions of the liver related to blood?

Answer 5

It regulates the chemical composition of blood and produces bile.

Question 6

What organs deliver secretions to the small intestine?

Answer 6

The liver, stomach, and pancreas.

Question 7

Where are liver secretions stored before reaching the small intestine?

Answer 7

In the gallbladder.

Question 8

How is bile stored and concentrated before reaching the small intestine?

Answer 8

Stored and concentrated in the gallbladder beneath the liver.

Question 9

What is the weight of the adult liver?

Answer 9

Approximately 1.5 kg.

Question 10

How many lobes does the liver have?

Answer 10

Four lobes: right, left, quadrate, and caudate.

Question 11

Where is the gallbladder located?

Answer 11

Attached to a depression on the inferior surface of the liver.

Question 12

How does bile travel from the liver to the small intestine?

Answer 12

From the liver via the common hepatic duct → stored in gallbladder → released via common bile duct.

Question 13

What is the porta hepatis?

Answer 13

An opening between the lobes of the liver through which the hepatic artery, portal vein, and bile duct pass.

Question 14

What structures enter or exit through the porta hepatis?

Answer 14

Hepatic artery, portal vein, and bile duct.

Question 15

What adheres to the liver’s inferior surface?

Answer 15

The gallbladder.

Question 16

What is the function of the hepatic artery?

Answer 16

Transports oxygenated blood to the liver.

Question 17

What is the function of the hepatic portal vein?

Answer 17

Transports nutrient-rich blood from the intestines to the liver.

Question 18

Where does blood leave the liver?

Answer 18

Through the hepatic vein.

Question 19

What are hepatocytes?

Answer 19

Specialized liver cells arranged in plates that perform metabolic and secretory functions.

Question 20

What are sinusoids?

Answer 20

Capillary-like vessels in the liver that carry blood between plates of hepatocytes.

Question 21

What do sinusoids contain?

Answer 21

Blood from the portal vein and hepatic macrophages (Kupffer cells).

Question 22

What do Kupffer cells do?

Answer 22

Phagocytose bacteria and debris in the blood.

Question 23

What are bile canaliculi?

Answer 23

Small channels between hepatocytes that collect bile and drain into bile ductules.

Question 24

How are hepatocytes arranged?

Answer 24

In liver lobules (hepatic lobules), separated by stroma (connective tissue).

Question 25

What are the components of a liver lobule?

Answer 25

Central vein, radiating hepatocytes, hepatic sinusoids, and Kupffer cells.

Question 26

What is a hepatic triad?

Answer 26

A small branch of the hepatic artery, a small branch of the portal vein, and a bile ductule.

Question 27

What supplies blood to sinusoids?

Answer 27

Branches of the hepatic artery and portal vein.

Question 28

What type of blood is in sinusoids?

Answer 28

A mix of oxygenated blood from the hepatic artery and nutrient-rich blood from the portal vein.

Question 29

Where does blood go after sinusoids?

Answer 29

Collected in the central vein, then flows to the right and left hepatic veins.

Question 30

Where do hepatic veins drain?

Answer 30

Into the inferior vena cava.

Question 31

Where is bile secreted?

Answer 31

Into bile canaliculi by hepatocytes.

Question 32

What are the digestive functions of hepatocytes after a meal?

Answer 32

They secrete bile to aid digestion.

Question 33

What do hepatocytes absorb from the blood?

Answer 33

Glucose, amino acids, iron, vitamins, and other nutrients for metabolism or storage.

Question 34

What do hepatocytes remove from the blood?

Answer 34

Hormones, toxins, bile pigments, and drugs.

Question 35

What do hepatocytes secrete into the blood?

Answer 35

Albumin, lipoproteins, clotting factors, and other products.

Question 36

What do hepatocytes do between meals?

Answer 36

Break down glycogen and release glucose into the blood.

Question 37

What substances are taken up by hepatocytes from portal blood?

Answer 37

Glucose, amino acids, iron, vitamins, and other nutrients.

Question 38

What are some products secreted by hepatocytes into the blood?

Answer 38

Albumin, lipoproteins, clotting factors.

Question 39

How much bile do hepatocytes produce daily?

Answer 39

About 250–1,500 ml per day.

Question 40

What are the components of bile?

Answer 40

Bile salts, phospholipids (lecithin), cholesterol, inorganic ions, and bile pigments (bilirubin).

Question 41

What is bilirubin and where does it come from?

Answer 41

A yellow bile pigment from hemoglobin breakdown.

Question 42

What are the three ways the liver detoxifies the blood?

Answer 42

Secretion into bile, Kupffer cell phagocytosis, and chemical modification by hepatocytes.

Question 43

What is an example of chemical modification in the liver?

Answer 43

Converting ammonia into urea.

Question 44

How is urea removed after formation?

Answer 44

Introduced into blood and excreted by kidneys.

Question 45

What happens to glucose when blood levels are high?

Answer 45

Liver stores it as glycogen (glycogenesis).

Question 46

What happens to glucose when blood levels are low?

Answer 46

Liver breaks down glycogen (glycogenolysis) and releases glucose.

Question 47

What process allows the liver to make glucose from amino acids?

Answer 47

Gluconeogenesis.

Question 48

How does the liver regulate fats?

Answer 48

Through lipogenesis (storage) and lipolysis (breakdown).

Question 49

What are ketone bodies and when are they formed?

Answer 49

Energy molecules formed from fatty acids (ketogenesis), especially for the brain.

Question 50

What is enterohepatic circulation?

Answer 50

The cycle of bile acids, bilirubin, and drugs between liver, bile, intestine, and back via portal vein.

Question 51

How does bile enter and return in enterohepatic circulation?

Answer 51

From liver → bile canaliculi → bile duct → intestine → absorbed → portal vein → liver.

Question 52

What happens to digestion products absorbed in the intestine?

Answer 52

Delivered to liver via hepatic portal vein.

Question 53

What happens to blood after passing liver capillaries?

Answer 53

Leaves the liver via hepatic veins.

Question 54

What happens to some substances released in bile?

Answer 54

They are reabsorbed in the small intestine and returned to the liver.