Week 5 quiz Flashcards
What structure is used to represent sphingolipids?
Inverted L
How long is the carbon chain for sphingolipids?
18 Carbons
What are the two main components of sphingolipids?
Fatty acid + sphingosine
What kind of bond forms between sphingosine and fatty acids?
Amide linkages
What kind of molecule is formed through the linkage of sphingosine to fatty acids?
Ceramide
What groups interact between sphingosine and fatty acids?
Carboxyl and amino groups
Which group on a ceramide reacts with other polar groups?
Hydroxyl on first carbon (from bottom)
What two kids of polar groups can interact with ceramides?
Phosphate and carbohydrate groups
If a phosphate group bonds with a ceramide, you get a _
Phosphosphingolipid
If a carbohydrate group bonds with a ceramide, you get a
Glycosphingolipid
If a single sugar bonds with a ceramide you get _
Cerebroside, like glucocerbroside
If two or more sugar groups bond with a ceramide you get
A globoside
If an N-acetyl neuraminic acid (NANA) bonds with a ceramide, you get _
A ganglioside
Give an example of a phosphosphingolipid
Sphingomyelin
Which kind of transporter only transports one solute molecule?
Uniport transporter
Which kind of transporter transports two molecules in the same direction?
Symport transporter
Which kind of transporter transports two solute molecules in opposite directions?
Antiport transporter
Give a main function of glucose transporters in the body
Shuttling glucose between the liver and the bloodstream
Glucose transporters are _
Uniports
Is glucose transport active or passive?
Passive, molecules go down the conentration gradient
Name a symport confomrational transporter found in renal eputhelial cells in the kidney
Na+/glucose transporter
What type of transporter is Na+/K+ ATPase?
Antiport
How do ions flow against conentration gradient (active transport) in Na/K ATPase?
Using the energy coming from the hydrolysis of ATP
What are normal blood glucose levels in humans?
60-150mg/dL
How long does it take for glycogen stores to be depleted?
Around 10-18 hours
How is glucose made available to cells during a fasted state with depleted glycogen stores?
Through the process of gluconeogenesis?
Compare gluconeogenesis to glycolysis
Gluconeogenesis is like the reverse process. 3 steps in glycolysis are irreversible so alternative pathways replace them in gluconeogenesis
Opening a channel and allowing molecules to flow down conentration gradient is called _
Facilitated diffusion
Why do fatty acids not form linear structures?
Because of the tetrahedral shape of carbon
Why do saturated fats have higher melting/boiling points?
Chains can be densely packed/folded, interactions require more energy to overcome
At room temperature, oils are in a _ state, they are composed mainly of _
Liquid, unsaturated fats
At room temperature, fats are in a _ state, they are composed mainly of _
Solid, saturated
2 main differences between omega and delta naming system for fatty acids:
Delta counts carbons starting at carbonyl group
Omega starts furthest away from carbonyl
Delta names all double bonds
Omega only notates first double bond
Molecules which are amphiphiles are _
Hydrophobic and hydrophilic (at different sites)
What is a triglyceride molecule?
A glycerol bonded to three fatty acid chains
Which kind of reaction bonds fatty acids at hydroxyl groups of glycerol?
Dehydration
Hydrolysis of triglycerides produces _
Fatty acids and glycerol
Which atoms are found in phospholipids?
P, O, C, H, N
What are the main components of phospholipids?
Phosphate group (N in R group), glycerol and two fatty acid chains
Give 4 examples of steroid hormones:
Testosterone, estradiol(estrogen), cholesterol and cortisol
Steroid rings have a _ structure
Fused 4 ring
Waxes are long _ chains with many different _
alkyl, functional groups
The basic unit of terpenes is
Isoprene
Isoprene is a _ carbon molecule
5
Number of isoprene uits in a terpene =
number of carbons in chain / 5
Eicosanoid lipids function as
signalling molecules
What are nucleosomes?
Groups of 8 histone proteins with DNA wrapped around twice
What is the function of H1 histones
Links and stabilises nucleosomes, wraps them in to a spiral called a solenoid
What is heterochromatin?
Chromatin that is transcriptionally inactive
What is euchromatin?
Chromatin that is transcriptionally active
Singer and Nicholson developed the _ model of membranes
Fluid mosaic
