Carbohydrates & Lipids Flashcards
Unit 2: Biomolecules
What does Carbon allow?
Carbon contains four electrons in is outer shell allowing it to form four covalent bonds with other elements
What bonds are the strongest?
Covalent Bonds! Carbon based molecules are very stable
Are carbon chains straight?
No! They aren’t due to bond angles
Define Carbohydrates
They are composed of carbon, hydrogen, and oxygen and have a general fomula of CH2O
Define Macromolecules
They have a very large number of atoms
How are macromolecules created?
They are created by linking together subunits called monomers.
What forms polymers?
Condensation Reactions!
Define condensation reactions
They are a reaction that links two molecules together and releases a smaller molecule.
What’s needed in the condensation reaction?
Energy (ATP)
Define polysaccharides
A condensation reactions that keep adding more and more monomer links
Example of a polysaccharides
Starch, glycogen and cellulose
Define glycosidic bonds
The bond that links the glucose (Glucose + Glucose + Glucose …)
What do deconstruction of polymers provide?
They can provide energy or to reuse parts for new construction
What deconstructs?
Hyrolysis reactions
What are monosaccharides?
Suagars with between 3 and 7 carbon atoms.
Charateristics of monosaccharides
They (especially glucose) are soluble so easy to transport
What’s created when monosaccharides are broken down?
ATP, useful as a quick energy source.
What happens to prevent dissolved glucose affecting osmolarity?
Lots of dissolved glucose increases osmolarity, so it is stored in glycogen (starch) which is not soluble.
What can alpha glucose molecules produce?
Alpha glucose molecules linked together can form starch (in plants) and glycogen (in animals)
What are two types of starch?
Amylopectin and amylose
Define tensile strength
Maximum stress that a material can withstand while being stretched or pulled before breaking
What are cellulose made up of?
They are made up of beta glucose
Functions of cellulose as a structural polysaccharides in plants?
They make up cell walls. Chemical nature gives it high tensil strength and provies support, does not burst even under high water pressures
What are glycoproteins used for
They are used for cell to cell recognition
Roles of glycoprotiens in cell to cell recognition
Helps to organize tissue an dallow identification of foreign cells that can be marked for destruction
What are lipids composed of?
Usually of three ftty acids, covalently bonded ot a 3 carbon coompound
Characteristics of lipids
They are hydrophobic! Insoluble in H2O but soluble in non-polar organic solvents
Define triglyceride
3 Fatty acids plus glycerol
What’s an ester bond?
Reaction that occurs between carboxyl group on fatty acid and hydroxyl group on the glycerol
What reactions occurs during the formation of triglyerides and phospholipids
Condensation reactions
What determines if it is an oil or a fat?
TYPE OF FATTY ACID
Define adipose tissue
Group of specialized cells that store fat/triglycerides (under the skin, around some organs). In animals, used for long term storage of energy
Characteristics of adipose tissue?
Chemically stable, do not contribute to the osmotic pressure.
Adipose tissue as shock absorber
They are a good shock absorber as they are liquid at body temp.
Adipose tissue as heat conducters
They are poor heat conductors
Adipose tissue as a storage?
they are difficult to digest and cannot be easily transported so more useful for long term energy, not quick access
Define Steroids
They are group of lipid molecules that don’t have fatty acids chains but share the hydrophobic nature like other lipids.
What are steroids identified based on?
- Four fused non polar carbon rings
- 3 cyclohexane rings and one cyclopentane ring
Define steroid hormone
It’s a steroid that functions as a signalling molecule within the body
