Week 7 Flashcards
What are the characteristics of asexual reproduction?
- It’s based on the mitotic division of nucleus
- It’s rapid and effective
- Offspring are clones of the parents
What’s binary fission?
A process in which every cell divide itself producing two identical cells
What are rhizomes?
Horizonatl underground stems that can give rise to new shoots
What are bubls and corms?
Short, vertical underground stems (corms are disc like but they lack the fleshy modified leaves that you can find in bulbs)
What are stolons?
Stems that extend out from the parent plants, forms roots at intervals and estabilish possibly independent plants.
Describe budding:
New individuals are formed as outgrowth or buds from the bodies of older animals
Describe regeneration:
Regenerated cells contain identical information to the severed arms
What are the disadvantages of asexual reproduction?
Cannot purge deleterious mutation and low diversity means less able to adapt to environmental change
What are spores?
Specialized cells that are capable of developing into new organisms.
What is gametogenesis?
The production of gametes through meiosis and it occurs in gonads
What is spermatogenesis?
The production of 4 sperm cells from a single male germ cell
What’s oogenesis?
The production of an ovule from a single female germ cell
What’s spawning or mating?
The process by which two gametes are brought together
What’s Fertilization?
The process by which two gametes fuse
What are the three steps of sexual reproduction?
- Gametogenesis
- Mating or Spawning
- Fertilization
What’s a gametophyte?
The haploid phase of the alternation of generation which produce gametes
What’s a sporophyte?
The diploid phase of the alternation of generation which produce spores
What’s heteromorphic sex cycle?
The two generations differ in terms of morphology
What’s isomorphic sex cycle?
The two generations are the same despite genetic differences
What’s haplontic sex cycle?
Most of the life cycle is haploid and the diploid phase is unicellular
What’s a diplontic sex cycle?
All cells except gametes are diploid
What’s antheriudium?
Is a male sex organ in which sperm are produced in large numbers
What’s archegonium?
Is a multicellular, flask shaped female sex organ with a long neck and a swollen base, which produce and protect a single egg
What’s homospory?
The condition in which land plants produce a single type of haploid spores
What’s heterospory?
The condition in which land plants have two different types of spores.
What’s dykariotic?
An organism that doesn’t have gametes cells but gamet nuclei that differe genetically from one another (n+n)
