Week 1: Major classes of organic molecules and their functions Flashcards
What is a molecule?
A group of atoms bonded together, representing the smallest unit of a chemical compound with its distinct properties.
What are organic molecules, and what are the major categories of organic molecules?
Organic molecules are molecules that contain carbon.
The four major categories are:
* Carbohydrates
* Lipids
* Protiens
* Nucleic acids
What are carbohydrates? And what are their function?
A type of organic compound composed of carbon, hydrogen and oxygen.
Carbohydrates serve as a primary source of energy for living organisms.
They play a vital role in:
* Cell signalling.
* Maintaining cell structure of certain tissues.
* Assisting in synthesising other essential molecules.
What are the major forms of carbohydrates?
- Sugars
- Starches
- Glycogen
What are the 3 major groups of carbohydrates based on the size of the molecules?
- Monosaccharides (sugars)
- Glucose
- Fructose
- Galactose
- Disaccharides (starches)
- Lactose
- Sucrose
- Maltose
- Polysaccharides
- Glycogen
How many carbon atoms, and how are they arranged, in monosaccharides?
Monosaccharides contain a single chain of carbon atoms between 3-7 long.
What are dissacharides made up of, and how many carbon atoms do they contain?
Disaccharides are made from 2 monosaccharides joined together.
They contain 12 carbon atoms, and have the general formula C12H22O11.
What are the 3 important dissacharides in nutrition and what are they composed of?
- Maltose (malt sugar): Glucose+glucose
- Sucrose (table sugar): Glucose+fructose
- Lactose (milk sugar): Glucose+galactose
How many monosaccharides do polysaccharide molecules typically contain? And what is the main polysaccharide in the human body?
Polysaccharide molecules contain tens to hundreds of monosaccharides.
The main polysaccharide in the human body is glycogen, which is stored in the liver and skeletal muscle.
What is the process that forms disaccharides by combining monosaccharides?
Dehydration synthesis
What are lipids?
A diverse class of molecules that are essential for energy storage, cell membrane structure and signalling.
Types of lipids include fats, oils and phospholipids,
Phospholipids are a type of lipid with a hydrophilic (attracting water) head and hydrophobic (repelling water) tails, forming the basic structure of cell membranes.
What percentage of lean adult body mass is made up of lipids?
Lipids make up 18-25% of lean body mass in adults.
What are the 4 major types of lipids?
- Fatty acids
- Triglycerides
- Phospholipids
- Steroids
What are the 2 main functions of fatty acids?
- Generate ATP (adenosine triphosphate) - chemical energy.
- Forms triglycerides and phospholipids.
What are the 3 main functions of triglycerides?
- Protection
- Insulation
- Store energy