Ana Flashcards
Define carbohydrates in chemical terms
Carbohydrates are polyhydroxy aldehydes or ketones or compounds which give these substances on hydrolysis.
Carbohydrates are the most abundant macromolecules in nature.
What is the general molecular formula of carbohydrates?
C_nH_{2n}O_n or (CH_2O)_n, where n > 3
Carbohydrates contain carbon, hydrogen, and oxygen.
List the three major groups of carbohydrates
- Monosaccharides
- Oligosaccharides
- Polysaccharides
What are the functions of monosaccharides?
- Provide energy
- Source of energy when oxidized in respiration
- Making disaccharides
- Making polysaccharides
What are the types of monosaccharides based on functional groups?
- Aldoses (aldehyde group)
- Ketoses (ketone group)
What is mutarotation?
The spontaneous change between the α and β configuration of carbohydrates
This phenomenon is due to the presence of an asymmetric carbon atom.
What determines the D or L form of a sugar?
The orientation of the -OH and -H groups around the carbon atom adjacent to the terminal primary alcohol carbon
-OH on the right indicates D-series, on the left indicates L-series.
What are epimers?
Sugars that differ from one another only in configuration with regard to a single carbon atom
Examples include glucose and mannose.
What are the chief functions of Pentoses?
- Synthesis of nucleic acids (ribose in RNA, deoxyribose in DNA)
- Synthesis of some co-enzymes (e.g., ribose in NAD and NADP)
- Synthesis of ATP needs ribose.
Name the biologically important disaccharides
- Sucrose
- Maltose
- Lactose
What type of linkage is present in maltose?
α-(1,4) glycosidic linkage
Maltose is formed from two D-glucose residues.
What is the structure of lactose?
Formed from the combination of β-D-galactose and β-D-glucose linked by β-(1,4) glycosidic linkage
Lactose acts as a reducing sugar due to a free carbonyl group.
What distinguishes sucrose from other disaccharides?
Sucrose lacks a free carbonyl group and is considered a non-reducing sugar
Formed by the condensation of α-D-glucose and β-D-fructose.
Fill in the blank: Carbohydrates serve as the main source and storage of _______.
[energy]
True or False: All monosaccharides are colorless crystalline compounds.
True
What is the importance of blood glucose control?
Controlled by different hormones and metabolic processes, with implications for diabetes and related health issues
Insulin dysfunction can lead to atherosclerosis, vascular diseases, and renal failure.
What are the classes of monosaccharides based on the number of carbon atoms?
- Trioses (C3)
- Tetroses (C4)
- Pentoses (C5)
- Hexoses (C6)
