Module 2 (part b) Flashcards
Amazon Molly
- Was the first vertebrate in which unisexuality was recognized.
- All individuals are females.
Parthenogenic Reproduction
Parthenogenesis occurs when females mate with, and receive sperm transfer from a male sailfin molly or a male shortfin molly.
(but there are no male mollies.)
Parthenogenesis
- In which the sperm do not fertilize the eggs, it only serves to activate the diploid eggs to develop
NOTE: All offspring produced are females that are clones (genetic copy) of their mother.
Parthenogenetic diploid species adult females are…
homozygous at all gene loci therefore all the progeny are also homozygous.
Apomixis (in plants)
Asexual reproduction within fertilization.
Sexual Reproduction Definition
Production of new individuals by joining of gamete to form a cell (zygote) by the process of fertilization.
Asexual Reproduction Advantage
- large number of offspring produced rapidly
- Only one individual required
Asexual Reproduction Disadvantage
- Limit or no genetic variation
Sexual reproduction of flowering plants…
-Self-fertilization
- Cross-fertilization ——> Pollination
Animals
- Cross Fertilization
Hermaphrodites Example
Earthworms and Planaria
Sequential Hermaphroditism
Some plants and animal species begin life as one sex, changing sometime to the other is a process called…
What does the loss of the dominant female prompts?
A sex change in her male partner and maturation of the most dominant immature fish as the new breeding male.
Sexual Reproduction
Production of new individuals by the exchange of genetic material form two individuals of different mating types.
Sexual Reproduction Advantage
- Increases genetic variation to new genotypes.
- Enhances reproductive success in changing environments
Sexual Reproduction Disadvantage
- Locate a mate
Conjugation
Two organisms fuse along a common surface and exchange genetic material (gene transfer ——> genetic variation).
- There are no increase in the number individuals.
Example; Paramecium
What does high genetic diversity means?
Greater ability of some individuals to survive in a changing environment.
Paramecium
- use both sexual and asexual reproduction
- Uses Binary Fission as asexual reproduction.
- Uses Conjugation as sexual reproduction.
Viruses
- consists of genetic material (nucleic acid, DNA, or RNA)
- Contained within a protective protein coat called a capsid.
- Do not contain all 4 biomolecule
- Do not have a cellular structure
- Unable to replicate outside of a living system
- Do not reproduce.
- They infect the cells of living organisms. “infectious agents” which cause disease.
Viroids
- Infectious particle of plants
- Do not have a cellular structure
- Depend upon enzymes of plant host for replication
- Lack proteins
- Consist of a small RNA molecule
- RNA of viroids do not code for any proteins
Prions
- Are non-living entities
- More simple than viruses
- Lack hereditary material (DNA or RNA)
- Do not have a cellular structure
- Infectious agent
(brain disorder)
Viruses, viroids and prions…
Are non-living entities and lack cellular structure.
Not capable of reproduction or “independent” metabolism.
Water
- Is the matrix of life.
- 60% body mass of most animals and 95% of some plants
- Maintains osmotic pressure in cells.