Experiment 2 - biochemical changes on postharvest in fruits and vegetables

Question 1

major componsent in most fruits and vegetables

Answer 1

water

Question 2

major factor affecting quality of fruits and vegetables

Answer 2

water loss or transpiration

Question 3

Effects of water loss to fruits and vegetables

Answer 3

wilting
shriveling
flacidness
soft texture
loss of nutritional value

Question 4

predominant energy sources for cells

Answer 4

carbohydrates

Question 5

carbohydrates representes what when an edible plant tissue is removed from the parent plant

Answer 5

carbohydrates represent tbe reserves necessary to maintain cellular function

Question 6

primary cell wall

Answer 6

a thin, flexible, and extensible layer formed while the cell is growing

Question 7

secondary cell wall

Answer 7

forms as a thick layer inside the primary cell wall after the cell is fully grown

Question 8

middle lamella

Answer 8

forms at the interface between adjacent plant cells; promotes cell-to-cell adhesion

Question 9

cellulose

Answer 9

linear polymer of beta-1,4-linked beta glucose residues deposited in the wall to form microfibrils

Question 10

hemicellulose

Answer 10

branched and are mainly composed of several neutral sugars like xylose

Question 11

pectins

Answer 11

linear or branched polymers that are rich in galacturonic acid and dispersed throughout the primary cell wall

Question 12

Happens due to the loosening of the hemicellulose-cellulose network, solubilization and depolymerization of pectin and loss of pectic side chains

Answer 12

cell-wall swelling

Question 13

formula for percent calcium pectate

Answer 13

%CP = (g of precipitate/g of sample in aliqout)*100%

Question 14

what are the three types of carbohydrates

Answer 14

structural
soluble
storage

Question 15

carbohydrates used in metabolic processes such as glycolysis and secondary metabolic pathways

Answer 15

soluble carbohydrates

Question 16

examples of soluble carbohydrates

Answer 16

glucose
fructose
sucrose

Question 17

an insoluble homoglucan composed of two polymers of glucose, amylopectin and amylose

Answer 17

starch

Question 18

amylopectin

Answer 18

branched molecule linked by alpha-1,4-glycosidic bonds with occasional alpha-1,6-glycosidic bonds

Question 19

amylose

Answer 19

linear polysaccharide joined by the alpha-1,4-glycosidic linkages

Question 20

most common organic acids in edible plant

Answer 20

mono-, di-, and tri-carboxylic acids

Question 21

typically associated with less mature fruits

Answer 21

organic acid accumulation

Question 22

responsible for the aroma of many fruits

Answer 22

esters

Question 23

plant secondary metabolites that affect the appearance (color), taste, and flavor of edible plant tissues

Answer 23

phenolic compounds

Question 24

enzymatic oxidation of phenolic compounds occurs by the action of

Answer 24

polyphenol oxidase (ppo)

Question 25

regulate metabolism via their enzymatic functions

Answer 25

proteins and amimo acid

Question 26

play a major role in the storage of nitrogen for growth in plants

Answer 26

free amino acids and their water-soluble derivatives

Question 27

4 general types of lipids in plants

Answer 27

triacyglycerides phospholipids waxes isoprene-derived lipids

Question 28

these occurs if antioxidative defense systems are compramised

Answer 28

lipid peroxidation and membrane deterioration

Question 29

plant volatole organic compounds

Answer 29

are secondary metabolites that play an important role in biotic interactions and abiotic stress responses

Question 30

plant hormones

Answer 30

chemical compounds that potentiate a signaling network and regulate the metabolic systems

Question 31

examples of plant growth regulators

Answer 31

ethylene auxins gibberellins abscisic acid cytokinins

Question 32

ethylene is produced from

Answer 32

methionine

Question 33

phenotypic changes in response fk ethylene are determined by

Answer 33

1. perception of hormone 2. transduction of signal through gene expression regulators 3. expression of gene and synthesis of proteins sensitive to the received ethylene signal

Question 34

compositioms of fruits

Answer 34

water carbohydrates organic acids phenolics proteins and amino acids lipids pigments volatile organic compounds hormones