Ch. 6.4 Life substances-part 2

1. Ch. 6.4 Life substances-part 2

2. Proteins:contain C, H, O,N, & sometimes S Multipurpose molecules

3. Proteins • Function: • many, many functions • hormones • signals from one body system to another • insulin • movement • muscle • immune system • protect against germs • enzymes • help chemical reactions

4. insulin pepsin collagen (skin) Proteins Examples • muscle • skin, hair, fingernails, claws • collagen, keratin • pepsin • digestive enzyme in stomach • insulin • hormone that controls blood sugar levels

5. H | —C— | H amino acid amino acid amino acid amino acid amino acid – – – – C—OH —N— O || H Proteins amino acids • Building block = • 20 different amino acids There’s20 of us… like 20 differentletters in analphabet!Can make lots of differentwords variable group

6. H | —C— | H amino acid amino acid amino acid amino acid amino acid – – – – C—OH —N— O || H Proteins amino acids • Building block = • 20 different amino acids There’s20 of us… like 20 differentletters in analphabet!Can make lots of differentwords variable group

7. amino acid amino acid amino acid amino acid amino acid Amino acid chains • Proteins • amino acids chained into a polymer • Each amino acid is different • some “like” water & dissolve in it • some “fear” water & separate from it

8. Amino acids can be linked by peptide bonds • Cells link amino acids together by dehydration synthesis • The bonds between amino acid monomers are called peptide bonds PEPTIDEBOND Dehydrationsynthesis Dipeptide Amino acid Amino acid

9. collagen For proteins: SHAPE matters! • Proteins fold & twist into 3-D shape • that’s what happens in the cell! • Different shapes = different jobs growthhormone hemoglobin pepsin

10. It’s SHAPE that matters! • Proteins do their jobs, because of their shape • Unfolding a protein destroys its shape • wrong shape = can’t do its job • unfolding proteins = “denature” • temperature • pH unfolded“denatured” In Biology, it’s not the size, it’s the SHAPEthat matters! folded

11. Enzymes • Enzymes are important proteins found in living things. An enzyme is a protein that speeds up the rate of a chemical reaction. • (SEE SEPARATE LECTURE.)

12. Nucleic acids • A nucleic (noo KLAY ihk) acid is a complex biomolecule that stores cellular information in the form of a code. • 1. DNA (deoxyribonucleic acid) contains the instructions used to form all of an organism’s proteins. • 2. RNA (ribonucleic acid) forms a copy of DNA for use in making proteins. • They ultimately control the life of a cell

13. proteins DNA Nucleic Acids • Function: • genetic material • stores information • genes • blueprint for building proteins • DNA  RNA  proteins • transfers information • blueprint for new cells • blueprint for next generation

14. sugar N base phosphate Nucleic acids nucleotides • Building block = nucleotide – nucleotide – nucleotide – nucleotide • 5 different nucleotides • different nitrogen bases • A, T, C, G, U Nitrogen basesI’m the A,T,C,G or Upart!

15. sugar sugar sugar sugar N base N base N base N base phosphate phosphate phosphate phosphate Nucleotide chains • Nucleic acids • nucleotides chained into a polymer • DNA • double-sided • double helix • A, C, G, T • RNA • single-sided • A, C, G, U strong bonds RNA

16. DNA • Double strand twists into a double helix • Weak hydrogen bonds between nitrogen bases join the 2 strands • A pairs with T • A :: T • C pairs with G • C :: G • the two strands can separate when our cells need to make copies of it weak hydrogenbonds