Foundations Exam Part 1 Flashcards
What are some examples of lipids in the body?
Fatty acids, cholesterol, and other hydrophobic molecules
What is the most essential component of a cells membrane?
The phospholipid
What is the definition of an epimer?
Diastereomers whose configuration differs only at one asymmetric carbon
Aldoses and ketoses form ________
cyclic structures
Glucose cyclizes to form Two Pyranose Ring Structures
These are called _______-type diastereomers
Anomer-type Diasteromers
Alpha-anomer has -OH at C-1 on ________ side of ring from -CH2OH at chiral carbon atom that determines ____ or ____ configuration
Alpha-anomer has -OH at C-1 on OPPOSITE side of ring from -CH2OH at chiral carbon atom that determines D or L configuration
Beta-anomer has -OH on the ____ side of ring as the CH2OH at the chiral carbon atom
Beta-anomer has -OH on the SAME side of ring as the CH2OH at the chiral carbon atom
D-Fructose Cyclizes to a 5-membered ______ ring structure
Furanose
List the Purines
Adenine and Guanine
LIst the Pyrimidines
In DNA: Thymine and Cytosine
In RNA: Uracil and Cytosine
Definition: Base attached to a pentose sugar
Nucleoside
Definition: Monophosphate, diphosphate, and triphosphate of esters of nucleosides
Nucleotide
A-T base pairs form ______ hydrogen bonds
A-T base pairs form 2 hydrogen bonds
G-C base pairs form _____ hydrogen bonds
GC base pairs form three hydrogen bonds and are more stable than AT-rich regions
Proteins are ______ chains of _______ covalently linked amino acids
Proteins are linear chains of COVALENTLY linked amino acids
Polypeptide chains are directional and the chains are denoted from ____ to _____ end
Polypeptide chains are directional and conventionally chains are denoted from N to C end.
Secondary structures of proteins entail
alpha helixes (side chains are on the outside of the helix)
Beta strands align in parallel or antiparallel orientation to form Beta sheets
Hydrogen bonding rich in secondary structures
In tertiary structures of proteins, what is the folding driven by?
Folding is driven by the burial of hydrophobic residues from water
Where do proteins undergo post-translational modification?
In the ER and Golgi body proteins under post-translational modification
What is Glycosylation?
Glycosylation is a form of protein modification in the secretory pathway.
Secretory proteins have a signaling sequence at the beginning of them
What are Signal recognition particles and in what processes do we find them?
SRPs bind to signaling sequences in glycosylation. Glycosylation is a form of post-translational modification.
SRP binds to receptors on the endoplasmic reticulum and move protein through pores in the ER.
Where does glycosylation occur?
Glycosylation occurs in either the ER or the Golgi.
What are the roles of glycosylation?
-N linked on asparagine, O-linked on Serine
-Assists in protein folding to reach the correct shape
-Enhance protein solubility
-Stabilize the protein against denaturation
-protect the protein from proteolytic degradation
-target the protein to specific subcellular locations
-Serve as a recognition signal for carbohydrate-binding proteins (lectins) or provide special properties
Write out the answers to the following questions
write out
What are some of the main types of lipids found in the body?
- TRIACYLGLYCEROLS (aka triglycerides the most common lipid)
- Phospholipids
- Sterols
Be able to describe properties of glucose and fructose
Glucose and fructose are functional isomers of each other.
They have the same molecular formula C6H12O6
-But the have DIFFERENT functional groups in the chemical formula
-GLUCOSE HAS AN ALDEHYDE GROUP
FRUCTOSE HAS A KETONE AS A FUNCTIONAL GROUP
Give some examples of disaccharides and polysaccharides
Common disaccharide examples:
1. Sucrose (glucose-fructose)
2. Lactose (galactose-glucose)
3. Maltose (glucose-glucose)
Examples of polysaccharides:
Starch, cellulose, glycogen
Describe the structure of an amino acid
Amino acids are made up of a basic amino group (-NH2), and acidic carboxyl group (-COOH), and an organic R group that is unique to each amino acid
Describe the different types of amino acid side chains
There are 4 different classes of amino acid side chains
1. non polar and neutral
2. polar and neutral
3. acidic and polar
4. basic and polar
How do Enzymes catalyze reactions?
Sometimes reactions have too big of an activation energy to occur,
the enzyme reduces that thermodyanmic barrier so that a reaction can occur at a useful rate
For this happen, the enzyme and the substrates must bind together, form a transient complex where the reaction occurs, then releases the products
What is the protoplasm composed of?
Protoplasm= cytoplasm + karyoplasm
Who proposed the cell theory and when?
Robert Hooke in 1839
What are the five components of the Cell Theory?
- Organisms are composed of cells
- Each cell is composed of small mass of protoplasm containing cytoplasm in its inside and a plasma membrane with or without cell wall on outside
- New cell arise from pre-existing cells
- All cells are similar in physiology and chemistry
- The activities of all organisms are a result of interactions between the cells
What are the basic features of a eukaryotic cell?
- plasma membrane
- cytosol that contains organelles
- chromosomes that carry genes
What molecule primarily makes up the cell membrane?
- LIPIDS
Describe the phospholipid bilayer