Lecture 31

Question 1

Key adaptations for life on land

Answer 1

• cuticle
• stomata (gas exchange)
• vascular tissue (xylem, lignin)
• stem, roots, leaves
• secondary growth
• egg protected on female
• embryo protected in sedd
• SPOROPHYTE dominance
• pollination

Question 2

Moss characteristics

Answer 2

• most primative
• No vascular tissue, no rootes
• thin cuticle
• stomata
• motile gametes
• gametophyte is dominant generaton

Question 3

Fern characteristics

Answer 3

• roots and vascular tissue for water uptake and transport
• sporophyte dominates
• motile gametes still (reliant on free water)

Question 4

Land Plant life cycle

Answer 4

Gametophyte –> egg and sperm –> fusion –> SEX –> zygote –> Sporophyte –> Meiosis –> spores –> gametophyte

Question 5

Seed plants are better at land stuff because

Answer 5

1) development of secondary growth
2) produces two types of spores (megaspores in ovules and microspores in pollen)
3) Reproduced by seeds
4) Males gametes transported in pollen

Question 6

Seed plant life cycle

Answer 6

Megagametophyte and microgametophyte –> egg and sperm–> zygote –> Sporophyte –> meiosis –> micro and mega spores –> mega and microgametophytes

Question 7

Angiosperm biodiversity and dominance

Answer 7

1) Vegetative or morphological features
- vessels in xylem
- sieve cells
2) reproductive features
- carpels
- double fertilization: one gives rise to embryo, other rise to endosperm
- pollination: diverse mechanisms
- flowers