Germination

Question 1

What occurs in germination?

Answer 1

 Germination is the resumption of growth
following dormancy.
 A thick seed coat protects the seed during
dormancy.
 Abscisic acid inhibits chemical reactions within
the seed.

Question 2

What do seeds require?

Answer 2

• Water for chemical reactions
• Oxygen for cellular respiration
• Warmth for enzymes to work efficiently

Question 3

How does temperature and climate affect germination?

Answer 3

In winter: enzymes in seeds degreade hte abscisic acid

In spring: the abscisic acid is gone and the seed can germinate

Question 4

When do seeds need light?

Answer 4

only in seeds with thin seed coat (where there
is a space in the forest canopy letting light through,
indicating a space for a new plant to grow)

Question 5

List some factors that could damage the seed coat.

Answer 5

 Mechanical abrasion
 Fire
 Acid
 Stratification- kept cold for an extended time
 Freezing & thawing

Question 6

What happens in the last stages of maturing of seeds?

Answer 6

• seed dehydrates until water content is only 5-15% of its weight
• embryo stop growing and remains dormant until seed germinates

Question 7

What occurs when a seed starts to germinate?

Answer 7

the seed takes up water and the food
store is mobilized to provide the nutrients for plant
growth and development.

Question 8

What occurs when the seed have been exposed to proper conditions?

Answer 8

• water and oxygen taken in through the seed coat
• hormone gibberellin is produced and starts chemical reactions occurring
• hydrolytic enzymes start to break down starch reserves to release glucose for growth
• this provides energy to synthesise new molecules for growth
• the seed coat breaks open and root radicle emerges, followed by the shoot (plumule)