BackGeneral Biology Key Concepts
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Terms in this set (33)
Biotic factors are living components like plants and animals; abiotic factors are non-living like temperature, water, oxygen, and soil.
Interactions between different species including competition, exploitation (predation, herbivory, parasitism), and positive interactions (mutualism, commensalism).
Primary producers make their own food; primary consumers eat producers; secondary and tertiary consumers eat other consumers.
Sexual reproduction involves gamete fusion; asexual reproduction includes budding, fission, and parthenogenesis without gamete fusion.
Organisms that have both male and female reproductive organs, capable of producing both sperm and eggs.
Oogenesis is the production of eggs; spermatogenesis is the production of sperm cells.
External fertilization occurs outside the body; internal fertilization occurs inside the body.
Acrosomal reaction allows sperm to penetrate the egg; cortical reaction prevents polyspermy after fertilization.
Cleavage is rapid cell division after fertilization; blastula is the hollow ball of cells formed, containing the blastocoel cavity.
Gastrulation forms three germ layers: ectoderm, mesoderm, and endoderm, and creates the archenteron (primitive gut).
Formation of the neural tube, neural crest, and notochord during early development.
A neuron consists of a cell body, dendrites (receive signals), and an axon (transmits signals).
Sensory neurons carry signals to CNS; motor neurons carry signals from CNS; interneurons connect neurons within CNS.
CNS includes brain and spinal cord; PNS includes all nerves outside CNS.
Resting potential is the stable voltage across membrane; action potential is a rapid depolarization and repolarization transmitting nerve signals.
Myelin sheath insulates axons to speed up conduction of action potentials.
Electrical synapses allow direct ion flow; chemical synapses use neurotransmitters and ligand-gated ion channels.
Chemicals released at synapses to transmit signals between neurons or to muscles.
Endocrine signals travel through blood; paracrine affect nearby cells; autocrine affect the same cell that released them.
Lipid-soluble hormones pass through membranes and bind intracellular receptors; water-soluble hormones bind cell surface receptors.
Natural selection favors traits that increase survival and reproduction; adaptations are traits shaped by natural selection.
Homologous structures share common ancestry; analogous structures have similar function but different origins.
Genetic drift is random allele frequency change; gene flow is allele transfer between populations.
Prezygotic barriers prevent mating or fertilization; postzygotic barriers reduce hybrid viability or fertility.
Allopatric speciation occurs with geographic isolation; sympatric occurs without geographic isolation.
Gram-positive bacteria have thick peptidoglycan walls; Gram-negative have thin walls and outer membrane.
Explains origin of eukaryotic organelles by engulfing prokaryotes, including secondary endosymbiosis events.
Life cycle alternating between multicellular haploid gametophyte and diploid sporophyte stages.
Protostomes have spiral cleavage and mouth develops first; deuterostomes have radial cleavage and anus develops first.
Acoelomate no body cavity; pseudocoelomate body cavity not fully lined; eucoelomate true coelom fully lined with mesoderm.
Open system hemolymph bathes organs directly; closed system blood circulates within vessels.
Innate immunity is nonspecific and immediate; adaptive immunity is specific and has memory.
Nephron filters blood: filtration in glomerulus, reabsorption and secretion along tubules, concentrating urine.