Plant Bio 2: Developing Better Food Flashcards Preview

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Flashcards in Plant Bio 2: Developing Better Food Deck (36):
1

What are the major human nutritional deficiencies?

Fe 20-40%
Vitamin A 10%
Iodine
Zinc

2

What has the highest source of vitamin A?

Beef liver

3

What is the absorption and transportation of vitamin A like?

Fat soluble vitamin

Absorbed and transported with lipids

4

Where is vitamin A stored?

In the liver

5

What is b-carotene?

Pro-vitamin A

6

What does B-carotene Di oxygenase become?

2x retinal molecules
Retinol
Retinoic acid

7

What is a major role of vitamin A?

Part of the visual pigment rhodopsin

8

What are forms of vitamin A also involved in?

Gene expression
Maintenance of epithelial tissue
Regulation of growth and differentiation cells- including some cells of the immune system

9

As part of rhodopsin, what does retinal bind to?

The protein opsin

10

In regulation of gene expression, what does retinoic acid bind to?

Protein receptor

11

What does retinoic acid (RA) binding to DNA receptors (transcription factors) lead to?

Modification of gene expressions

RA involved in early embryonic development

12

What are the symptoms of vitamin A deficiency?

Dry cornea and eventual blindness (xerophthalmia)
Night blindness (insufficient retinal for rhodopsin formation)
Impaired immune function

13

How many people affected by vitamin A deficiency?

750 million

14

What are vulnerable groups for different vitamin A deficiencies?

Children from 6 months to 6 years

Pregnant women
Lactating women

15

What countries have highest vitamin A deficiencies?

Developing countries; Africa, Asia, western pacific
39

16

How many children develop xerophthalmia?

5-10 million

17

What changes GGPP (geranylgeranyl-PP) to phypotene + 2 pyrophosphates?

Phytoene synthase (PSY)

18

What changes phytoene + 2 pyrophosphates to c-carotene?

Phytoene desatorase

19

What changes c-carotene to lycopene?

Zeta carotene desaturase
Carotene isomerase

20

What changes lycopene to b-carotene (pro-vitamin A) and a-carotene?

Lycopene cyclase (LCY)

21

Where does the carotenoid pathway occur?

In chloroplasts

22

Which enzyme is rice endosperm?

Lycopene cyclase (LCY)

23

What is gene 1 in golden rice?

PSY daffodil

24

What is gene 2 in golden rice?

Gene from bacteria erwinia=
carotene desaturase 1 CRT 1

25

What is the ingo potrykus idea?

To increase the b-carotene content in rice grain (endosperm) because it's a staple food source, by using genetic engineering, or a reconstitution of carotenoid pathway in rice endosperm

26

Genetic engineering process?

DNA
-transcription
RNA
-translation
Protein
Trait

27

How do you add genes into a plant genome?

Hijack a natural process: eg agrobacterium tumefaciens (a natural genetic engineer)

28

What is transferred from Ti plasmid on the bacterium to the plant genome?

Everything between the LB and the RB on the T-DNA (transfer DNA)

29

What's in the left border sequence?

Promoter; glutelin
ATG; coding sequence; PSY

Terminator poly-A tail

30

What's in the middle gene 1 sequence?

Glutelin
Choloroplast targeting signal
CRT 1

31

What's in the third gene for golden rice?

355 (promoter)
Encode for resistance to antibiotic or herbicide

32

Example of possible encodings?

Kanamycin
Hygromycin

33

What is a 355 gene do?

Expresss gene everywhere aka a constitutive expression

34

What are the results of the golden rice experiment?

Increased levels of b-carotene

Didn't have high enough levels of carotene to supply provitamin needs

35

What did the second golden rice use?

PSY gene from maize

36

Limitations of golden rice?

Not enough to meet daily recommended amounts (GR2)

People also require zinc and other elements in their diet

Limitations from culture and tradition