1.4 - Carbs Flashcards
What are macromolecules?
Macromolecules (also called polymers) are made from joining together multiple small organic molecules (called monomers or building blocks)
What are the 4 types of macromolecules?
- Carbohydrates (sugars)
- Lipids/fats (fatty acids)
- Proteins (amino acids)
- Nucleic acids (DNA/RNA/nucleotides)
What are some of the roles of macromolecules?
- Energy storage
- Structural support
- Catalysis (as a catalyst for chemical reactions)
- Transport
- Protection and defense
- Regulation of metabolic activities
- Maintenance of homeostasis
- Means for movement, growth, and development
- Heredity
What are monomers?
Monomers are simple and identical building blocks that link together to form polymers
- They are made of the essential chemicals (N, O, C, H)
What are polymers?
Polymers (also called macromolecules) are made from joining together multiple small organic molecules (called monomers or building blocks)
Define dehydration synthesis
To form a polymer, monomers are linked together, and a water molecule is released as a by-product. Such a process is called dehydration synthesis.
Define hydrolysis
Polymers can be broken down by adding a water molecule. Such a process is called hydrolysis.
What are the categories of biomolecules?
Carbohydrates, proteins, DNA & RNA
- Lipid monomers are less persistent than the above monomers. Consequently, lipids are less-readily described using the same polymeric terms. Lipids don’t really have polymers.
What are monosaccharides?
Monosaccharides are carbohydrate monomers. They are SIMPLE, SINGLE sugars
What are polysaccharides?
Polysaccharides are carbohydrate polymers (aka multiple monosaccharides linked together)
What are amino acids?
Amino acids are protein monomers
What are polypeptides?
Polypeptides are protein polymers (aka multiple amino acids linked together)
What are nucleotides?
Nucleotides are DNA/RNA monomers
What are polynucleic acids?
Polynucleic acids are DNA/RNA polymers (aka multiple nucleotides linked together)
Define carbohydrates
Carbohydrates are carbon molecules with hydrogen and hydroxyl (OH) groups
- Remember CHO
What are the main roles of carbohydrates?
- They act as energy storage and transport molecules
- They also serve as structural components
What are the 4 major categories of carbohydrates?
- Monosaccharides
- Disaccharides
- Oligosaccharides
- Polysaccharides
How many monosaccharides make up a disaccharide?
A disaccharide is made up of two monosaccharides put together
How many monosaccharides make up an oligosaccharide?
An oligosaccharide is made up of 3-20 monosaccharides put together
How many monosaccharides make up a polysaccharide?
A polysaccharide is made up of hundreds/hundreds of thousands of monosaccharides put together
What monosaccharide is contained in every living cell?
Glucose
How do organisms acquire glucose?
Organisms acquire glucose (or the energy to make glucose) from eating plants
Why do cells break down glucose?
Cells break down glucose to release energy
When glucose is broken down, what are the final products?
Carbon dioxide and water
What are the two existing formations of a glucose molecule?
Glucose molecules can either be:
- A straight chain of carbon, hydrogen, and oxygen (less likely)
OR - A ring of carbon, hydrogen, and oxygen (>99% likely)
- When dissolved in water, both forms exist equally
How are monosaccharides bound together?
Monosaccharides link together to form di/oligo/polysaccharides through dehydration synthesis, and these bonds are called Glycosidic linkages
What type of bond is a Glycosidic linkage?
A type of covalent bond that joins a carbohydrate (sugar) molecule to another group
What are the 3 hexose sugars?
Glucose, galactose, fructose
- Glucose and galactose are classified as aldoses (CHO), fructose is classified as a ketose (CO)
How is sucrose formed?
Sucrose is formed by linking two monosaccharides (a glucose and a fructose)
Why is sucrose an important plant carbohydrate?
- Water soluble
- Easily transported in plant circulatory system
Which group cannot synthesize sucrose?
Animals
What is sucrose called?
- Table sugar
- Cane sugar
- Beet sugar
How is maltose formed?
Maltose is formed by linking two monosaccharides (a glucose and a glucose)
How is lactose formed?
Lactose is formed by linking two monosaccharides (a glucose and a galactose)
What is lactase?
Lactase is an enzyme that allows people to digest lactose by breaking it back into its original monosaccharides (glucose and galactose)
What is lactose intolerance?
Lactose intolerance involves individuals who lack the enzyme lactase and are unable to digest lactose (break it into glucose and galactose).
- 75% of the world population is lactose intolerant
What are the 2 plant starches called?
Amylose (not branched) and amylopectin (slightly branched)
What is the animal starch called?
Glycogen (highly branched)
What are starches?
Starches are molecules that store glucose
What is cellulose?
Cellulose is a polysaccharide comprised of many glucose molecules
Why is cellulose an excellent structural material?
Cellulose is an excellent structural material because it is much more stable chemically than starch. This makes it much more difficult to hydrolyze (break down) using chemicals or enzymes.
- Most organisms cannot digest cellulose
What kind of organisms can digest cellulose?
Organisms that can digest cellulose include the microorganisms living in the gastrointestinal tract of many organisms typified especially by cows and termites and many fungi (i.e., the things that eat the wood off fallen trees)
What is chitin?
Chitin is another example of a structural carbohydrate. Chitin is found in the exoskeletons of insects, spiders, and crustaceans. Chitin is also found in the cell walls of fungi. Chitin is leathery in pure form but is hardened in most uses via the deposition of calcium carbonate.
