뒤로General Biology: Exam II Study Guide Flashcards
02:32
이 집합의 용어 (28)
Abiotic synthesis is the formation of organic molecules from inorganic substances without the involvement of living organisms, a key step in the origin of life.
The RNA world hypothesis proposes that early life was based on RNA molecules that both stored genetic information and catalyzed chemical reactions.
A protocell is a simple, pre-cellular structure with a membrane-like vesicle that exhibits some characteristics of living cells, such as maintaining an internal environment.
Endosymbiosis is the theory that eukaryotic cells originated when a prokaryotic cell engulfed another, which then became an organelle like mitochondria or chloroplasts.
The fossil record is the collection of all known fossils and their placement in rock formations and sedimentary layers, providing evidence of evolutionary change over time.
Relative dating estimates the age of fossils by their position in sediment layers, while radiometric dating uses decay of radioactive isotopes to determine absolute age.
Half-life is the time required for half of the radioactive parent isotope in a sample to decay to its daughter isotope, used to estimate fossil ages.
The Cambrian explosion was a rapid diversification of multicellular animal life about 540 million years ago, leading to many major animal groups.
A mass extinction is a widespread and rapid decrease in biodiversity, distinct from background extinction, often followed by adaptive radiation.
Adaptive radiation is the rapid evolution of many species from a common ancestor, often after mass extinctions or colonization of new habitats.
Heterochrony is an evolutionary change in the timing or rate of developmental events, affecting organism morphology.
Hox genes are a group of homeotic genes that control the body plan and the placement of structures during embryonic development.
Phylogeny is the evolutionary history and relationships among species or groups of organisms.
Homology refers to traits inherited from a common ancestor, while analogy refers to similar traits evolved independently by convergent evolution.
A clade is a group of organisms that includes an ancestor and all its descendants, representing a monophyletic group.
Maximum parsimony is a principle that the simplest phylogenetic tree, requiring the fewest evolutionary changes, is preferred.
Prokaryotes are unicellular organisms without a nucleus, including bacteria and archaea.
Gram-positive bacteria have thick peptidoglycan cell walls and stain purple; Gram-negative bacteria have thin walls and an outer membrane, staining pink and often more antibiotic-resistant.
Binary fission is the asexual reproduction process in prokaryotes where one cell divides into two genetically identical daughter cells.
Horizontal gene transfer is the movement of genetic material between organisms other than by descent, increasing genetic diversity in prokaryotes.
Obligate aerobes require oxygen; obligate anaerobes are poisoned by oxygen; facultative anaerobes can survive with or without oxygen.
Endospores are resistant, dormant structures formed by some bacteria to survive harsh conditions.
Cyanobacteria are photosynthetic bacteria important for oxygen production and are ancestors of plant chloroplasts.
The major eukaryotic supergroups are Excavata, SAR, Archaeplastida, and Amorpheans, each with distinct members and characteristics.
Secondary endosymbiosis occurs when a eukaryotic cell engulfs another eukaryotic cell that already contains a primary plastid.
Dinoflagellates are alveolates with two flagella; some cause harmful algal blooms called red tides due to toxin production.
Plasmodial slime molds form a multinucleate mass, while cellular slime molds exist as individual cells that aggregate under stress.
Mutualism benefits both species, commensalism benefits one without affecting the other, and parasitism benefits one at the expense of the other.