Lecture 8: Plant Reproductive Strategies

Question 1

Asexual Advantages and Disadvantages

Answer 1

Ad: No mate required
       Rapid and saves energy
       Adapted to current environment
Disad: Low genetic variablility
            Adaptation difficult
             Retards evolution

Question 2

Sexual Advantages and Disadvantages

Answer 2

Ad:
High genetic variability
Facilitates adaptation
Facilitates evolution

Disad:
Mate required
Energy costly
Slower than asexual

Question 3

Algal Reproduction and Life cycle

Answer 3

Laminaria (Kelp)
Sporangia (2n) 
      |
Inside sporangia - meiosis occurs
      |
Release zoospores into sea
      |                              |
Females                  Males
     |                               |
Gametophyte (n)      Gametophyte (n)
     |                               |
Develop egg             Develop sperm
     |                               |
              Fertilize
                   |
           Zygote (2n)
                   |
    Rest structure is (n)
                   |
          Sporophyte
                   |
           Sporangia

Question 4

Bryophyte life cycle

Answer 4

Primary role of gametophyte is production of male and female gametes
Male gamete is flagellate cell (sperm) - must swim to female gamete

Question 5

Define heterosporous

Answer 5

Two types of sporangia

Question 6

Describe Pollen

Answer 6

Has resistant outer wall - protects gamete from desiccation and UV light

Question 7

Apomixis

Answer 7

Seed production without pollination / fertilization

-> Asexual reproduction