[MT 6317 LEC] Unit 3.1: Carbohydrates

(c) morisete

Carbohydrates

Primary source of energy for brain, erythrocyte, and retina, cells in human

Carbohydrates

Major food source and energy supply for the body and are stored primarily as liver and muscle glycogen

glycogen

Carbohydrates is a major food source and energy supply for the body and are stored primarily as liver and muscle ________________

- Hyperglycemia

- Hypoglycemia

Carbohydrates are involved in two disease states. What are those?

Carbohydrates

_________________ is important for the diagnosis of diabetes mellitus

Carbohydrates

Substances containing carbon, hydrogen, and oxygen

1

How many water molecules are there per carbon of Carbohydrates?

C=O; -OH

All carbohydrates contain ___________ and _________functional group

True

T/F: Other functional groups may attach to the carbon chain of a carbohydrate.

○ Size or number of the base carbon chain

○ Location of the CO functional group

○ Number of sugar units

○ Stereochemistry of the compound

Carbohydrates are classified based on what structural properties? (4)

● Trioses

● Tetroses

● Pentoses

● Hexoses

What are the classification of carbohydrates based on size or number of base carbon chains? (4)

Glyceraldehyde

What is the smallest carbohydrate, a three carbon compound?

- Aldose

- Ketose

What are the classification of Carbohydrates based on the location of CO (Carbonyl) functional group?

Aldose

terminal carbonyl group (O=CH); aldehyde group

Ketone

carbonyl group in the middle linked to carbon atom; ketone group

- Fischer Projection

- Haworth Projection

What are the classification of Carbohydrates based on the carbohydrate models? (2)

Fischer Projection

Aldehyde or ketone group at the top; Carbons are numbered starting at the aldehyde or ketone head

Haworth Projection

Represents compound in cyclic form that is more representative of actual structure;

Haworth Projection

Formed when the functional group reacts with alcohol group on the same sugar to form a ring

- Monosaccharides

- Disaccharides

- Oligosaccharides

- Polysaccharides

What are the classification of Carbohydrates based on the number of sugar unit?

Monosaccharides

Can not be hydrolyzed further

Monosaccharides

May be trioses, pentoses, and so on

Disaccharides

Formed through a glycosidic bond

glycosidic bond

Disaccharides are formed through a...

Disaccharides

Maltose (Glucose + Glucose), Sucrose (Fructose + Glucose), Lactose (Galactose + Glucose) are examples of...

Maltose

Glucose + Glucose

Sucrose

Fructose + Glucose

Lactose

Galactose + Glucose

Polysaccharides

Complex carbohydrates like Starch

- D type/form

- L type/form

- Enantiomers

What are the classification of Carbohydrates based on the stereoisomers?

Stereogenic centers

This allows spatial arrangement to happen (free movement), forming stereoisomers

D Type/form

If the hydroxyl group is found on the right of the carbonyl group

D Type/form

Stereoisomer usually found in the human body

L Type/Form

If the hydroxyl group is found on the left of the carbonyl group

enantiomers

nonsuperimposable stereoisomer

True

T/F: The moment we swallow food, digestion starts.

Salivary Amylase

What is the first enzyme for digestion?

polymers

Most ingested CHO are _____________.

- Starch

- Glycogen

What are the most ingested CHO polymers?

gut

Disaccharide enzymes are found at the ____________

Glucose

This is the only CHO that can be directly used for energy or storage

- Embden Meyerhof Pathway

- Hexose Monophosphate Shunt

- Glycogenesis

What are the pathway for Glucose Metabolism? (3)

Glycogenesis

Formation of Glycogen (storage) from glucose

Meyerhof Pathway

Glucose is broken down into two three-carbon molecules of pyruvic acid

Meyerhof Pathway

The most important thing to remember is that glucose will either be converted to pyruvate (aerobic) and lactate (anaerobic)

pyruvate; lactate

In Meyerhof Pathway, glucose will either be converted to _______________ (aerobic) and _______________ (anaerobic)

○ Glycerol

○ Fatty acids

○ Ketones

What are the other substrates in Meyerhof pathway?

ATP used = 2

ATP produced = 4

Net ATP = 2

Fill in the information for Meyerhof Pathway?

ATP used =

ATP produced =

Net ATP =

forms new non-carbohydrate compounds

Gluconeogenesis

Citric Acid Cycle

Lipids & Proteins may transform into pyruvate to enter the _________________

Hexose Monophosphate Shunt

Detour of Glucose 6 Phosphate from the the glycolytic pathway to become 6-phosphogluconate

6-phosphogluconate

Hexose Monophosphate Shunt is a detour of Glucose 6 Phosphate from the the glycolytic pathway to become...

Glucose 6 Phosphate Dehydrogenase

What is the enzyme responsible for Hexose Monophosphate Shunt?

Hexose Monophosphate Shunt

Forms Ribose; Forms NADPH which reduces GS-SG, where its reduced form 2G-SH, is an antioxidant that prevents hemoglobin from being oxidized (if hemoglobin is oxidized, it cannot attach to oxygen; leading to loss of oxygen supply)

- ribose

- NADPH

Hexose Monophosphate Shunt forms... (2)

NADPH

This reduces GS-SG, where its reduced form 2G-SH, is an antioxidant that prevents hemoglobin from being oxidized (if hemoglobin is oxidized, it cannot attach to oxygen; leading to loss of oxygen supply)

2G-SH

This is an antioxidant that prevents hemoglobin from being oxidized (if hemoglobin is oxidized, it cannot attach to oxygen; leading to loss of oxygen supply).

Hexose Monophosphate Shunt

also known as Pentose Monophosphate Pathway

Pentose Monophosphate Pathway

Hexose Monophosphate Shunt is also known as...

Glycogen

storage form of glucose

Glycogenesis

Only when the body's energy requirements are being met does this pathway occur.

- Glycogenolysis

- Gluconeogenesis

When Glucose is Low, what processes occur? (2)

Glycogenolysis

This obtains energy through breaking down glycogen from the liver, entering the glycolytic cycle; Occurs during fasting

Glycolysis

Metabolism of glucose molecule to pyruvate or lactate for production of energy

Gluconeogenesis

Formation of glucose-6-phosphate from noncarbohydrate sources

glucose-6-phosphate

Gluconeogenesis is the formation of ___________________ from noncarbohydrate sources

Glycogenolysis

Breakdown of glycogen to glucose for use as energy

glycogenesis

Conversion of glucose to glycogen for storage

Lipogenesis

Conversion of carbohydrates to fatty acids

Lipolysis

Decomposition of fat

Liver

Pancreas

Other endocrine glands

What are the organs involved in the carbohydrate metabolism regulation? (2)

Liver

Where glycogen is stored

liver

The conversion of glucose to glycogen (& vice versa) occurs in the _______________.

Pancreas

This produces hormones involved in the regulation of carbohydrates

Insulin

Glucagon

What are the major hormones involved in Carbohydrate metabolism regulation?

Insulin

Increases glycogenesis and glycolysis

- Glycogenesis

- Glycolysisv

Insulin increases what processes? (2)

Insulin

Hormone that lowers down glucose concentration

○ Somatostatin

○ Epinephrine

○ Cortisol

○ Thyroxine

○ Growth hormone

What are the other hormones involved in carbohydrates? (5)

Insulin

The hormone that increases glycogenesis and glycolysis.

glycogen; pyruvate; acetyl-CoA

Action of Insulin

glucose → _________________ → _________________ → ___________________

Insulin

Increases lipogenesis; Decreases glycogenolysis

Glycogenesis = INCREASE

Glycolysis = INCREASE

Lipogenesis = INCREASE

Gycogenolysis = DECREASE

Increases or Decreases:

INSULIN

Glycogenesis =

Glycolysis =

Lipogenesis =

Gycogenolysis =

Glucagon

Increases glycogenolysis (glycogen → glucose)

Glucagon

Increases gluconeogenesis: fatty acids → acetyl-CoA → ketone, proteins → amino acids

acetyl-CoA; ketone, proteins; amino acids

Glucagon Gluconeogenesis

fatty acids → ________________ → _________________ → _____________________

Beta; Alpha; Delta

Insulin is formed at __________, Glucagon is formed at ___________, Somatostatin is formed at _______________

Pancreas

Where insulin, glucagon, and somatostatin is being secreted

Insulin

Formed in Beta cells of the islets of Langerhans in the pancreas

Beta cells of the islets of Langerhans

Insulin is formed in what structure of the pancreas?

Insulin

Primary hormone responsible for the entry of glucose into the cell

Insulin

A hypoglycemic agent that can lower blood glucose concentration

hypoglycemic

Insulin is a _____________ agent.

- Liver

- Skeletal Muscles

- Adipose Tissue

What are the major target of Insulin?

True

Increase blood glucose → Release of insulin → Glucose level returns to normal

T/F: Insulin surge occurs after eating

Glucagon

Formed in Alpha cells of the islets or langerhans in the pancreas

Alpha cells of the islets or langerhans in the pancreas

Glucagon is formed in what structure of the pancreas?

Glucagon

Released during stress and fasting states

Glucagon

A hyperglycemic agent that enhances glycogenolysis and gluconeogenesis to increases blood glucose concentration

hyperglycemic

Glucagon is a ________________ agent.