Biological Classification and Evolution

These flashcards cover key concepts related to biological classification, chemical evolution, and embryonic development, assisting students in understanding fundamental biological terminology and theories.

Miller-Urey Experiment

An experiment that simulated the early Earth's atmosphere to test if organic compounds could be made from inorganic ones.

Taxonomic Ranks

Hierarchy levels for classifying organisms: Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species.

Binomial Nomenclature

A two-word naming system for species comprising the genus (capitalized) and species (lowercase), both italicized or underlined.

Prokaryote

Cells that do not have a nucleus or membrane-bound organelles.

Eukaryote

Cells that have a nucleus and membrane-bound organelles.

Endosymbiotic Theory

Mitochondria comes from engulfing heterotrophic bacteria. Chloroplasts come from engulfing autotrophic bacteria.

Heterotrophic

Organisms that cannot produce their own food, instead requires carbs, proteins, fats.

Autotrophic

Organisms that produce their own food using sunlight or chemical energy.

Radial Symmetry

Body arrangement around a central axis, allowing division into symmetrical halves from the center.

Bilateral Symmetry

Body arrangement that can be divided into two equal halves along one plane, producing left and right sides.

Coelom

A fluid-filled body cavity lined by mesoderm, allowing organs to move and develop independently and fluid that cushions.

Blastopore

The opening that develops in the gastrulation stage, which can form the mouth or anus.

Diploblastic

Organisms develop with two germ layers: ectoderm and endoderm.

Triploblastic

Organisms develop with three germ layers: ectoderm, mesoderm, and endoderm.

Pharyngeal Slits

Grooves in the pharynx that develop into slits opening to the outside, characteristic of chordates.

Derived Characters

Features that evolved in a particular group, distinguishing them from ancestral traits.

Cleavage

Rapid cell divisions that occur in fertilized eggs before the development of a blastula.

Zygote

The fertilized egg that undergoes cleavage to form an embryo.

3 Domain System

Bacteria, Archaea, Eukarya

6 kingdoms

Plantae, Animalia, Fungi, (multicellular, eukaryotic) Protista (eukaryotic, unicellular, multicellular) Eubacteria, Archaebacteria (unicellular, prokaryotic)

Cladistics

Taxonomic system based on evolutionary ancestry

Clades

Group of species that include an ancestral species and its descendants

Cladograms

Diagrams that show the evolutionary relationships among a group of organisms

Shared Ancestral

A character that originated in the ancestor of the group

Shared Derived

An evolutionary trait unique to a particular group

Evidence used to classify organisms

1) structural

• primary basis for grouping organisms based on obvious physical similarities

2) biochemical

• information about DNA, RNA, and proteins for relating organisms

3) cytological

• classification based on cell structure and number of chromosomes

4) embryological

• uses the embryo (how it develops and structures present) to distinguish

5) behavioural

• uses cues such as dances, patterns, and calls as means of distinguishing closely related species

6) fossils

• useful in connecting modern-day organisms with those that are extinct

Kingdom animalia tissues

ZYGOTE goes through cleavage to develop EIGHT CELL STAGE then to the formation of a BLASTULA which goes through GASTRULATION to form a GASTRULA that then develops the ENDODERM, ECTODERM, and BLASTOPORE.

Protosomes

Cleavage

• spiral and determinate

Coelom Formation

• solid masses of mesoderm split

Fate of Blastopore

• Mouth develops (PMA)

Deuterstomes

Cleavage

• radial and indeterminate

Coelom Formation

• folds of archenteron for coelom

Fate of Blastopore

• anus develops (DAM)

Coelomates

Animals with fluid filled body cavity with a lining from mesoderm.

Psuedocoelom

Fluid filled cavity partially lined with tissue. Organs are loosely held in place and not as organized.

Acoelomate

Lacks a body cavity between the digestive tract and body wall.

Shared derived characters in Chordates

1) Notochords

• flexible rod between digestive tube and nerve cord

• provides skeletal support

2) Dorsal, hollow nerve cord

• nerve cord develops into central nervous system: brain and spinal cord

3) Pharynael slits or clefts

• grooves in pharynx called pharynael clefts develops into slits that open to the outside

4) Muscular, post anal tail

• tail posterior to the anus

• greatly reduced during embryonic development

• contains skeletal elements and muscles, proving a propelling force in aquatic species