Study Notes on Carbohydrates
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Chapter Overview: Carbohydrates
Diabetes and the Role of Nurses
- Role of Diabetes Nurses:
- Help patients learn to monitor their medication and blood sugar levels.
- Educate patients to look for symptoms of diabetic complications, including:
- Diabetic nerve damage
- Vision loss
- Importance of the Endocrine System:
- Knowledge of the endocrine system is crucial as it is often involved with:
- Obesity
- Other related diseases
15.1 Carbohydrates: Definitions and Functions
- Definition of Carbohydrates:
- Major source of energy from our diet.
- Composed of three elements:
- Carbon
- Hydrogen
- Oxygen
- Also known as saccharides, which means "sugars."
- Learning Goal:
- Classify a monosaccharide as an aldose or a ketose.
- Indicate the number of carbon atoms in the monosaccharide.
Photosynthesis and Carbohydrates
- Production and Synthesis:
- Carbohydrates such as glucose are produced by photosynthesis in plants.
- Synthesized in plants from the following components:
- Carbon dioxide (CO2)
- Water (H2O)
- Energy from the sun
- Oxidation in Living Cells:
- In living cells, carbohydrates are oxidized to produce:
- Carbon dioxide (CO2)
- Water (H2O)
- Energy
Types of Carbohydrates
- Classification of Carbohydrates:
- Monosaccharides: The simplest carbohydrates.
- Disaccharides: Composed of two monosaccharides.
- Polysaccharides: Composed of many monosaccharides.
Monosaccharides: Structural Features
- Characteristics of Monosaccharides:
- Contain several hydroxyl groups attached to a chain of 3 to 8 carbon atoms.
- If a monosaccharide contains an aldehyde group, it is classified as an aldose.
- If a monosaccharide contains a ketone group, it is classified as a ketose.
- Have hydroxyl groups on all carbons except the carbonyl carbon.
Classification of Monosaccharides by Carbon Number
- Types of Monosaccharides Based on C Atoms:
- Triose: Contains three carbon atoms.
- Tetrose: Contains four carbon atoms.
- Pentose: Contains five carbon atoms.
- Hexose: Contains six carbon atoms.
- Example Classifications:
- Aldopentose: A five-carbon saccharide with an aldehyde group.
- Ketohexose: A six-carbon saccharide with a ketone group.
Visual Representation of Monosaccharides
- Examples of Monosaccharides:
- Glyceraldehyde (Aldotriose):
- Structure:
- CH2OH
- H
- H
- C=O
- H-C-OH
- HO-C-H
- H-C-OH
- CH2OH
- Threose (Aldotetrose):
- Structure:
- HO-C-H
- H-C-OH
- H-C-OH
- CH2OH
- Ribose (Aldopentose):
- Structure sketch similar to above.
- Fructose (Ketohexose):
- Structure sketch similar to above.
Learning Check: Identification
- Task:
- Identify whether the given monosaccharides are aldose or ketose, and classify them as tetrose, pentose, or hexose.
- Example Identifications:
- A: Aldohexose
- B: Ketopentose
Conclusion
- This section on carbohydrates provides foundational understanding critical for the study of biological systems, nutritional science, and diabetes management.