lecture #4 carbohydrates

Question 1

what are carbohydrates

Answer 1

• sugars: simple and complex

Question 2

how do they gives us energy?

Answer 2

broken down through cellular respiration

Question 3

how are they stored?

Answer 3

As long chains for short-term energy reserves in muscles and liver in animals

Question 4

what is the usual structure for a sugar

Answer 4

CH2O = 1:2:1 ratio

Question 5

what are the simple/complex sugars

Answer 5

monomers= simple
polymers= complex

Question 6

what are the classes of simple sugars

Answer 6

• Monosaccharides : monomers of carbohydrates, share the same molecular formula (C6H12O6), but arrangement of atoms differ

(know how to recongnise glucose, fructose, galactose)

• Disaccharides: 2 linked monosaccharides

Question 7

what are the types disaccharides, what are they composed of

Answer 7

sucrose = glucose + fructose (table sugar)
lactose = glucose + galactose (milk sugar)
maltose= glucose + glucose (brewing sugar)

Question 8

what is a monosaccharide

Answer 8

simplest carbohydrate (one piece)

Question 9

what is a disaccharide

Answer 9

doible sugars, two monosaccharides (2 pieces linked together by covalent bonds)

Question 10

what is a polysaccharide

Answer 10

macromolecules, polymers composed of many monosaccharides

Question 11

what is the linkage between the monosaccharides in polysaccharides

Answer 11

glycosidik linkages

Question 12

how do plants store energy (what type of storage polyssacharide do they store)

Answer 12

In the form of starch (molecule all oriented in the same direction)

Question 13

what are the monosaccharides (learn what they look like)

Answer 13

glucose
galactose
fructose

Question 14

what characterises each monosaccharide molecule

Answer 14

• glucose: 2 OH on the side, hexagone
• galactose: 1 OH , 1 H, hexagone
• fructose: 1 OH, 1 H, pentagone

Question 15

how do animals store energy

Answer 15

glycogyne (molecules not all oriented in the same direction)

Question 16

what is chitin

Answer 16

polyssacharide found in funcal cell walls and external skeleton of insects and other arthropods

beta linkages

Question 17

what are the 2 types of glycosidik linkages (ring formation) what do they do

Answer 17

alpha (hydroxil group below the first carbon)
beta (hydroxil group above the first carbon)

determine the 3D structure

Question 18

what does the starch molecule look like

Answer 18

chain of glucose molecules all in the same direction

Question 19

what does the cellulose molecule look like

Answer 19

chain of glucose molecules in opposite orientation

Question 20

what does the glycogen molecule look like

Answer 20

branched chain of glucose molecules resulting in a forked arrangement

Question 21

can we digest cellulose?

Answer 21

No, cannot digest the beta linkages from cellulose

Question 22

how can SOME animals digest cellulose (cows)?

Answer 22

cellulose-digesting prokaryotes and protists in its gut.

Question 23

what are the 2 forms of starch

Answer 23

amylose, amylopectin

Question 24

why is glucose in a ring confirmation?

Answer 24

It is more stable then a straight strain confirmation

Question 25

what is cellulose used for

Answer 25

support in plants (cell wall)

Question 26

what are the structural carbohydrates

Answer 26

• cellulose
• chitin

Question 27

what are the storage carbohydrates

Answer 27

• glycogyne
• starch

Question 28

what releases glucose

Answer 28

Hydrolysis of glycogen in these cells (animal)
in the starch (plants)

Question 29

what is the use of glycogen being brached (not straight)

Answer 29

The extensively branched structure of glycogen fits its function: More free ends are available for hydrolysis

Question 30

what is the most abundant organic compound on earth

Answer 30

cellulose

Question 31

what do sugar molecules look like

Answer 31

a carboxyl group (C double bond O) and multiple hydroxil groups OH