Ib bio final

(5) cladograms

Tree diagrams that show the most probable sequence of divergence in clades ( branch parts= nodes)

Stabilizing selection (5)

Average individuals are favored

Directional selection (5)

One extreme form of trait is favored (talk or short)

Disruptive selection (5)

Both extreme forms of a trait are flavored (and)

Gene pools & allele frequencies

Consists of all the genes & diff. alleles, present in interbreeding population. Allele frequencies change w/ time in populations

Mollusca

- Muscular foot & mantle
- Soft body
- Shell usually present
- No visible segmentation
- Mouth & anus (complete digestive tract)
Ex: snails, slugs, etc

Macro evolution

Populations of a species can gradually diverge into separate species by evolution

Speciation

The evolution of new species

Sexual reproduction & variation

Promotes variation in a species
- meiosis
(Independent assortment, crossing over)
- random fertilizer

Natural selection II

1) Struggle for survival bc of overproduction of offspring
2) Non- random survival
3) Natural selection occurs bc of the differential success in reproduction of members in population

Filicinophyta (ferns)

- water needed
- dispersal
- vascular tissue present
- wood may be present
- leaves, stem, root

Annelida

- bilaterally symmetric
- bristles often present
- segmented
- mouth & anus
Ex: earthworms

Amphibians

- soft, moist skin permeable to water
- simple lungs
- tetrapods (pentadactyl limbs)
- 4 legs
- external fertilization
- aquatic larval stage
- ectothermic

Chordata

Vertebrates apart of phylum

Platyhelminthes

- bilateral symmetry
- flat bodies
- unsegmented
- mouth no anus
Ex: tapeworms

Natural selection

Differential reproduction success of members of a population with particular inherited characteristics

Porifera

- no clear symmetry
- no tissues
- no mouth or anus
- sessile

Angiospermophyta the flowering plants

- vascular plants
- seed plants
( seeds protected by ovary which becomes fruit)
- has roots, stems, & leaves

Evolutionary adaptations

Inherited characteristics that enhance organisms survival and reproduction

Birds

- Skin w/ keratin feathers
- lungs
- 2 legs & 2 wings
- internal fertilization
- hard shell eggs
- warm blooded

Vestigial structures

Ex: whales/ snake
Hindlimb a, wings on flightless birds

Bryophyta (moss)

- Spores ensure dispersal
- no vascular tissue
- no roots

Cnidaria

- radial symmetry
- tentacles
- stringing cells (cnidocytesur)
- mouth no anus
Ex: jellyfish , corals, anemones

Domain

- Broader classification than kingdom
- DKPCOFGS
- all organisms are classified in 1 of 3 domains
(3 domain; eubacteria, archae, eukaryota)

Analogous structure

Structures have similar functions but unrelated in structure ( bird wings / butterfly wings)

Homologous structure

Similarities in structure when diff in function