Week 1 - chemicals building life Flashcards Preview

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Flashcards in Week 1 - chemicals building life Deck (22)
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1

water

- COHESION: of water via hydrogen bonds create SURFACE TENSION
- electronegativity creates a polar molecule w/ hydrogen bonding

2

isomers

structural: diff C skeleton
stereoisomers: same C skeleton
- differ in how groups attached
- enantiomers: D- sugars & L- AA

3

carbon

- can form up to 4 covalent bonds
- hydrocarbons: molecules of carbon & hydrogen
- nonpolar
- function groups: hydroxyl, carbonyl, carbooxyl, amino, sulfhydryl, phosphate, methyl

4

lipids

- insoluble → hydrophobic
- terpenes
- steroids
- prostaglandins
- in water, phospholipids form a BILAYER

5

lipids- triglycerides

- 1 glycerol + 3 fatty acids
- saturated: no double bond between C atoms → high melting point in ANIMALS
- unsaturated: 1 or more double bonds →low melting point in PLANTS

6

lipids - steroids

carbon skeleton is bent to form four fused rings
CHOLESTEROL: base steroid produces other steroids

7

proteins - functions

- enzyme catalysis
- defence
- transport
- support
- motion
- regulation
- storage

8

proteins - amino acid structure

- central carbon atom
- amino grtoup (NH2)
- carboxyl group (COOH)
- single hydrogen
- variable R group

9

proteins - peptides

- amino acids joined by dehydration - peptide bond
- long chains of AA spontaneously fold up
- FOLDING: congregation of hydrophobic AA in interior of protein & hydrophilic AA on ext

AA composition:
- hydrophobicity = solubility
- cysteine cont = stability

STRUCTURE DEFINES FUNCTION

10

proteins - levels of structure

1. seq. of amino acids
2. interaction of groups in peptide backbone: alpha helix & beta sheet
3. folded, stabilised by forces →final level of structure: single PP chain
4. arrangement of subunits → 2+ polypeptide

11

RNA

- ribose not deoxyribose
- uracil not thymine
- single polynucleotide strand
- specifies seq. of amino acids proteins

12

nucleic acid - nucleotide

Monomer: nucleotide → sugar + phosphate+ nitrogenous base
- PURINES: adenine, guanine
- PYRIMIDINES: thymine, cytosine, uracil
- nucleotides connected by PHOSPHODIESTER BONDS

13

DNA

encodes info
- AA seq. in protein
- base seq in DNA

double helix
- 2 polynucleotide strands
- hydrogenbonds

14

carbohydrates - function

- provide structure
- short & long term storage of energy
- part of nucleic acid backbone
- combine w/ proteins (glycoprotein)
- combine w/ lipids (glycolipids)
- involved in intracellular interactions between animal cells

15

carbohydrates - structure

MONOSACCHARIDE - simplest
DISACCHARIDE: transport or storage
POLYSACCHARIDE (dehydration) : storage: starch ; glycogen || struc supp: cellulose, chitin
- D-Glucose: most common → product of photosynthesis
- glycogen: in humans + broken down to release glucose when needed

16

amino

NH2
found in proteins, nucleic acids

17

sulfhydryl

SH
found in proteins

18

phosphate

PO4
found in nucleic acids

19

methyl

CH3
found in proteins

20

hyroxyl

-OH
found in: carbohydrates, proteins, nucleic acids, lipids

21

carbonyl

CO
found in: carbohydrates, nucleic acids

22

carboxyl

COOH
found in proteins, lipids