carbohydrates and lipids Flashcards
(25 cards)
carbon-carbon bond
*strong and stable
*found in ringed and linear form
*provide the basic framework for many molecules
*the longer, the stronger and more stable because there are more covalent bonds
non-metallic elements that can bind with carbon
phosphorus, nitrogen, hydrogen, oxygen, sulfur
macromolecules
play crucial roles in the structure and function of organisms
form through condensation
nucleic acids
lipids
proteins
carbohydrates
condensation reaction
1 molecule loses a hydroxyl group OH
1 molecule loses a hydrogen atom H
creation of a water molecule and a covalent bond
condensation of glucose molecules
OH group of carbon 1 attaches to OH group of carbon 4
= 1 water molecule & covalent bond called 1,4-glycosidic bond (disaccharide)
polysaccharides
starch, glycogen, cellulose
hydrolysis
breaking down macromolecules with water that breaks the covalent bonds
condensation and hydrolysis reactions allow for
recycling of nutrients
synthesis of new polymers needed for cellular processes
examples of hexoses
glucose (sugar found in nature), fructose (found in fruit), galactose (in dairy)
properties of glucose
- has 2 isomers a and b (if H is on top=a)
*soluble (polar because of Oh groups and the separation of charge (O- and C-H+ partially))
–> dissolves water and easily transported in blood
*stable (cyclic molecule with OH groups in the axial regions)
*can be oxidized
oxidation
chemical reaction involving the loss of an electron from a molecule/atom
- loser = oxidized
- gainer = reduced
occurs through
- addition of oxygen
- removal of hydrogen
- loss of electrons
involves ATP production
starch and 2 types
storage of glucose in plants
*amylose
- linear and coiled
- composed of 300-3000 units
- alpha-1,4-glycosidic bonds
> potatoes
*amylopectin
- branched, 3-dimensional
- alpha-1,4 AND 1,6-glycosidic bonds (latter creates branches)
- makes up ab 80% of starch molecules
> corn
where is starch stored
seeds and roots
- it is compact due to coiling and branching
- insoluble, maintains osmotic balance
- can be broken down in hydrolysis to release glucose to plant in need
glycogen
storage of glucose in animals
- branched, highly coiled and compact structure
- muscle and liver cells
- insoluble and large
backbone of alpha 1,4 and frequent 1,6 every 8-12 units to form branches
cellulose
a crucial part of plants’ cell walls
- prevents collapsing due to osmotic forces
- gives rigid and strong structure
- maintains shape and integrity
cellulose
- strong, rigid, lattice due to hydrogen bonds
- beta glucose
- straight chain, unbranched, grouped into bundles called microfibrils
(give tensile strength and are held together by hydrogen bonding by adjacent cells)
what are and where are glycoproteins found
proteins that have 1 or more carbohydrates attached
on cell membranes
in extracellular matrix
in secreted proteins
> determine blood type by their presence/absence on red blood cells (A and B antigens)
roles of glycoproteins
cell-cell recognition
receptors
ligands
structural support
lipid
non-polar & hydrophobic molecules
low solubility in water
dissolve in non-polar solvents
wax
triglyceride
steroid
phospholipid
triglyceride characteristics
typically solid in room temp.
can be consumed & synthesized
form through condensation of 1 glycerol & 3 fatty acid molecules
> every time a fatty acid joins glycerol, 1 water released
-> ester bond
wax
naturally on leaves of plants
insoluble
forms a waterproof layer to reduce transpiration
what are steroids composed of
four carbon rings that are fused together
phospholipid
amphipathic molecules that are essential components of cell membranes
types of fatty acids
saturated
- straight, linear
- solid
- no double bonds
> palm oil
unsaturated
- 1 (un, oleic acid) or more (polyun, soybean oil) double bond
- non-linear
cis unsaturated fatty acid
occur naturally
hydrogens attached to C around the double bond are on the same side of the molecule, causing a kink in the chain
