Busy. Please wait.
Log in with Clever

show password
Forgot Password?

Don't have an account?  Sign up 
Sign up using Clever

Username is available taken
show password

Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
Your email address is only used to allow you to reset your password. See our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Didn't know it?
click below
Knew it?
click below
Don't Know
Remaining cards (0)
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how


Biochemistry, Medicine, Phase 1

Amino acids (aa) (1) small organic molecules with a carboxylic acid (COOH) group and an amino group (H2N) both linked to their alpha-carbon atom plus a side chain (R); have 3 and 1 letter code
Side chain distinguishes one amino acid from another
Amino acids (2) protein building blocks; 20 universal amino acids; water soluble and electrically charged at physiological pH
Peptide bond covalent bond between two adjacent amino acids; formed by enzyme reaction; very strong; hydrolysis only by enzyme (digestion or lysosome)
Polypeptide more than one amino acid a covalently bonded to another amino acids
Amino group N-terminal of amino acid
Carboxyl group C-terminal of amino acid
L-form amino acids the only form found in proteins
D-form amino acids occur as part of bacterial cell walls and in some antibiotics
Glycine only amino acid without an optimal isomer
Positively charged amino acids arginine, lysine, histidine
Negatively charge amino acids aspartic acid, glutamic acid
Essential amino acids (adults) cannot be synthesised de novo by humans; we lack the necessary enzymes; threonine, methionine, lysine, valine, leucine, histidine, phenylalanine, tryptophan
Hydrophilic amino acids aspartic acid, glutamic acid, arginine, lysine, histidine, asparagine, glutamine, serine, threonine, tyrosine
Hydrophobic amino acids alanine, glycine, valine, leucine, isoleucine, proline, phenylalanine, methionine, tryptophan, cysteine
Other roles of amino acids taste enhancers (MSG; glu); neurotransmitters; synthesis of neurotransmitters
Epinephrine synthesised from tyrosine (1)
Dopamine synthesised from tyrosine (2)
Histamine synthesised from histidine
Serotonin synthesised from tryptophan
pKa of side groups measure of the ease with which groups give up their protons; at physiological pH the carboxyl and amino groups are attached to the alpha carbon and fully ionised; the lower the pKa the stronger the acid; only the pKa of R-groups are relevant (polar)
2.3 pKa of carboxyl group
9.8 pKa of amino acid group
pKa influence on structure and function of proteins; charge on amino acid depends on local pH
Phenylketonuria (PKU) defective phenylalanine hydroxylase (phe > try); reduced tyr results in reduced dopamine and melanin production; protein rich food increases phenylalanine levels which can be toxic
Albinism Defective tryosinase (try > melanin)
Created by: emmaallde
Popular Biochemistry sets




Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!
"Know" box contains:
Time elapsed:
restart all cards