How can beta-glucose molecules be bonded in a long chain?
Through numerous condensation reactions.
1 of 26
When alpha-glucose are bonded what do they form?
Coiled, spring-like chains.
2 of 26
What shape are beta-glucose chains once they've been condensed, and how many beta-glucose molecules can they contain?
Long and straight, and 10,000.
3 of 26
Are beta-glucose chains stronger or weaker than amylose?
Stronger.
4 of 26
What are beta-glucose polymer chains called?
Cellulose chains.
5 of 26
Where is cellulose found, and what makes it special?
Only in plants, and it's the most abundant structural polysaccharide in nature.
6 of 26
Cellulose fibres are arranged in a specific way to form what?
Plant cell walls.
7 of 26
Why do hydrogen bonds form between glucose monomers in cellulose molecules?
Because they contain so many OH groups.
8 of 26
How do cellulose molecules cross-link?
By hydrogen bonds.
9 of 26
What do 60-70 cellulose molecules cross-link to form?
Bundles called microfibrils.
10 of 26
What are microfibrils held together by, and what does this form?
Hydrogen bonds, and it forms macrofibrils.
11 of 26
What do macrofibrils have?
Great mechanical strength.
12 of 26
Where are macrofibrils embedded and what does this form?
They're embedded in a polysaccharide glue of substances called pectins which form cell walls.
13 of 26
What are 2 features of plant cell walls?
They give strength to each cell and support the whole plant.
14 of 26
What allows water to move through and along cell walls, and in and out of cells?
The arrangement of macrofibrils.
15 of 26
Why doesn't water in the cell cause it to burst?
Because the cell wall prevents it from bursting.
16 of 26
What are turgid cells and what is their role in a plant?
They are cells full of water and they help support the whole plant.
17 of 26
What does the arrangement of macrofibrils in a cell wall determine?
How cells in the wall can grow or change shape.
18 of 26
What does reinforcing cell walls with other substances provide?
Extra support or it makes them waterproof.
19 of 26
What does the polysaccharide chitin form?
The exoskeleton of insects.
20 of 26
What is the polysaccharide peptidoglycan the basis of?
Cell walls found around most bacteria.
21 of 26
Give 2 examples of monosaccharides and explain their characteristics, if they have any, and their role in organisms.
Glucose - small, soluble, sweet and crystalline. Provides energy via respiration. Deoxyribose - part of DNA,
22 of 26
Give an example of a disaccharide and explain it's characteristics and role in organisms.
Maltose - small, soluble, sweet and crystalline. A sugar obtained when starch is broken down. It can be split further to glucose.
23 of 26
Give 2 examples of polysaccharides and explain their characteristics and roles in organisms.
Starch & glycogen-molecules of alpha-glucose joined by condensation. Insoluble in water. Forms grains/granules. Energy-storage. Cellulose- molecules of beta-glucose joined by condensation. Insoluble in water. Strong. Structural. Found in plant cells.
24 of 26
Why do the differences between starch and cellulose occur?
Because of the differences between alpha- and beta-glucose.
25 of 26
Where is the OH in alpha- and beta-glucose.
Alpha - at C1 below the plane of the ring. Beta - at C1 above the plane of the ring.
26 of 26
Other cards in this set
Card 2
Front
When alpha-glucose are bonded what do they form?
Back
Coiled, spring-like chains.
Card 3
Front
What shape are beta-glucose chains once they've been condensed, and how many beta-glucose molecules can they contain?
Back
Card 4
Front
Are beta-glucose chains stronger or weaker than amylose?
Comments
No comments have yet been made