GLYCOLYSİS

Question 1

GLYCOLYSİS = GLYKYS (SWEET OR SUGAR) + LYSİS (SPLİTTİNG)

Answer 1

A molecule of glucose is degraded in a series of enzyme-catalyzed reactions to yield 2 molecules of 3-carbon compound pyruvate.

Question 2

GLYCOLYSİS = GLYKYS (SWEET OR SUGAR) + LYSİS (SPLİTTİNG) 2

Answer 2

During sequential reactions of glycolysis, some of the free energy released from glucose is conserved in form of ATP&NADH. Glycolysis- only source of metabolic energy in some mammalian tissues&cell types (erythrocytes, renal medulla, brain & sperm).

Question 3

GLYCOLYSİS CAN BE UNDERSTOOD ON FOUR LEVELS:(1,2)

Answer 3

1. Chemical interconversion steps, sequence of reactions by which glucose is converted to the pathway’s end products.
2. Mechanism of enzymatic conversion of each pathway intermediate to its successor.

Question 4

GLYCOLYSİS CAN BE UNDERSTOOD ON FOUR LEVELS:(3,4)

Answer 4

3.Energetics of the conversions. 4. Mechanisms controlling flux (rate of flow) of metabolites through pathway.

Question 5

GLUCOSE METABOLISM

Answer 5

Glucose entry into muscle & adipose tissue is controlled by insulin (GLUT-4), glucose enters other tissues independently of insulin.

Question 6

Glucose Transport
Glucose Transporters: Facilitated Diffusion:

Answer 6

• GLUT-1: Basal glucose uptake: Brain, placenta, kidney, ENT, erythrocyte and colon.
• GLUT-2: Beta cell glucose sensor: Small intestinal epithelium and kidney.

Question 7

Glucose Transporters: Facilitated Diffusion:

Answer 7

• GLUT-3: Basal glucose uptake: Brain, placenta, kidney, and other tissues.
• GLUT-4: Insulin-stimulated glucose uptake: Striated and cardiac muscle, adipose tissue -

Question 8

Glucose Transporters: Facilitated Diffusion:3

Answer 8

GLUT-5: Fructose transport: Jejenum, sperm.
- GLUT-7: Glucose 6-phosphatase transporter in the ER: KC and other tissues

Question 9

Glucose Transporters: Facilitated Diffusion:4

Answer 9

SGLT: Transport is actively carried out in the opposite direction to the glucose density difference. The required energy is derived from the electrical potential difference of sodium formed along the cell row. Secondary active transport. Na- Glucose co-transport:

Question 10

Glucose Transporters: Sodium Dependent Glucose Transporter

Answer 10

• (SGLT1): Glucose absorption: Small intestine, Renal tubules. - (SGLT2): Glucose absorption: Renal tubules.

Question 11

BASIC METABOLIC PATHWAYS OF CARBOHYDRATE METABOLISM

Answer 11

Glycolysis (Embden-Meyerhof Pathway): breakdown of glucose to pyruvate or lactate. Pyruvate Metabolism: Conversion of pyruvate to acetyl-CoA

Question 12

BASIC METABOLIC PATHWAYS OF CARBOHYDRATE METABOLISM 2

Answer 12

Tricarboxylic Acid Cycle (Krebs Cycle): Cleavage of the acetyl moiety in acetyl-CoA to CO2, formation of NADH and FADH2 reduced coenzymes

Question 13

CARBOHYDRATE METABOLISM

Answer 13

All organisms use glucose& other carbs as energy sources.
For some cells & organisms, GLUCOSE is the main source of energy.