Classification Processes - Unit 3, Topic 1 Flashcards
What is Taxonomy?
A system of classification that can be hierarchical depending on different levels of similarity of physical features, reproductive methods and molecular sequences.
What is Hierarchy?
The classification system is usually hierarchical (organised in layers of relatedness)
Lower levels - more specific
Higher levels - incorporate more information + more broad
What is Taxa? What are the 8 Taxa groups?
A level of hierarchical classification system
(e.g. kingdom, domain, family etc.)
ACRONYM:
Dear King Philip Came Over For Good Soup
D = Domain
K = Kingdom
P = Phylum
C = Class
O = Order
G = Genus
S = Species
What is Bionomial nomenclature?
A two-part name: Genus and Species (e.g. Homo saipens)
What are the 2 types of Reproductive Methods? Explain both.
Sexual and Asexual Reproduction.
Asexual Reproduction - Offspring produced from a single organism, without gametes. Offspring are genetically identical to their parents.
Examples of ASR:
- Binary Fission: When a single organism splits into two cells.
- Budding: When a new organism develops from the bud on a parent.
- Fragmentation - When the parent is broken into fragments, each fragment is capable of growing into another organism.
- Vegetative Propagation - When a new organism grows from the roots, leaves, stems etc.
- Spore Formation: releasing of spores.
Sexual Reproduction - 2 parents contribute genetic material through gametes, resulting in a genetically diverse offspring. Occurs in forms:
1. Internal Fertilisation: Fertilization occurs within the body.
2. External Fertilisation: Gametes are released into the environment.
SR can further vary based on:
a. Oviparous Organisms (Egg-layering)
b. Viviparous Organisms (Live-bearing)
c. Ovoviviparous Organisms: Egg develops in mother. There is no placental connection. Born live after hatching within the mother’s body.
What is R & K Selection? Explain both.
The parental investment + offspring survival
K - selected: Live in stable environments and have populations that are close to the maximum carrying capacity line.
K - selected traits:
- small # of offspring
- large amount of parental investment
- high survivorship
- large
- reach maturity later in life
- reproduce multiple times
- long life expectancy
- type I/II survivorship pattern
R - selected: Live in unstable environments and are much smaller than the carrying capacity.
- large # of offspring
- little to no parental investment
- low survivorship
- small
- reach maturity early
- reproduce once
- shot life expectancy
- type III survivorship pattern.
What is the classification of molecular sequences
Determining whether organisms share a common ancestor through sequences of molecules. Using ATGC or the order of amino acids.
what is a clade?
a group comprising all of the descendants of a particular ancestor organism.
What are the assumptions for cladistics?
(1) common ancestor,
(2) new species can form
(3) changes in characteristics overtime
What is the assumption for new species?
When speciation occurs, the new-gen will either be:
Plesiomorphic - same as their parent generation; same chacteristic/traits BUT not unique to their clade.
Apomorphic - novel evolutionary character unique to a particular clade and all its descendants.
What is the biological species concept?
organism that are able to interbreed and produce viable offspring.
Limitations:
- two populations never have a chance to interbreed
- organisms that reproduce asexually.
- fossils
What is the morphological species concept?
based on physical characteristics
Limitations: almost all populations are made up on non-identical individuals (morphology is misleading)
What is the phylogenetic species concept?
The smallest group of individuals having a common ancestor is often determined through genetic analysis; and evolutionary relationships among organisms.
What is a Interspecific Hybrid?
The crossing of two species that are from the same genus. (often cannot be viable/fertile)
What are the 4 types of species interactions?
- Competition - when species compete for the same resources, mate. Can be inter/intraspecific
- Symbiosis (relationships where at least one species benefits)
- parasitism: one species benefits, one species is harmed.
- commensalism: one species benefits, one is neither harmed nor benefited.
- mutualism: both species benefit - Predation - one organism kills (predator), one organism is killed/consumed (prey).
- Disease - interaction with a disease-causing organism (pathogens/parasite) and its host.
