Origin of Life on Earth, Manifestations and Characteristics of Life, and Levels of Organization Flashcards
According to this theory on the origin of life, the emergence of life on earth may have been influenced by supernatural or divine forces.
Special creation
This hypothesis states that the “seeds” of life exist all over the universe and can be propagated through space from one place to another.
Extraterrestrial origin/Panspermia
Variations of the Panspermia hypothesis:
Litho panspermia (interstellar panspermia), Ballistic panspermia (Interplanetary panspermia), Directed panspermia
This states that life may have evolved from non-living matter like mud, straw, and other decaying and rotting matter.
Spontaneous origin
He conducted a scientific experiment in 1988 to see if maggots would develop on their own.
Francesco Redi
He demonstrated that life originated from pre-existing life and rejected the theory of spontaneous generation by proving that the maggots came from fly eggs.
Louis Pasteur
Their experiments refuted the theory of spontaneous generation.
Needham’s and Spallanzani’s
The one who put fort the first “modern” theory for how life came into existence in 1923
Russian biochemist Oparin
Supported Oparin in 1928
British evolutionary biologist Haldane
Postulates that life may have developed through a series of organic chemical reactions that resulted in increasingly complex biochemical structures
Oparin-Haldane model
It was supported by the different species of finches on the Galapagos Islands, known as Darwin’s finches
Biological evolution
Prominent elements in the atmosphere of prehistoric earth:
Hydrogen, oxygen, carbon, sulfur, phosphorus, nitrogen
A pigment that absorbs light, helped plants capture solar energy during photosynthesis.
Chlorophyll
According to this theory, the first RNA molecules that could copy themselves independently of other molecules were simple RNA molecules that existed on Earth.
RNA world theory
It is supported by the discovery of pieces of RNA that can copy RNA strands longer than themselves.
DNA
They are proteins that catalyze reactions.
Enzymes
Science that studies life.
Biology
Several key characteristics or functions of all living organisms:
Order, sensitivity or response to stimuli, reproduction, adaptation, growth and development, regulation, homeostasis, and energy processing
Organisms are highly organized structures that consist of one or more cells.
Order
Term referred to as cell components
Organelles
Organs respond to diverse stimuli.
Sensitivity
A process where tiny bacteria can move toward or away from chemicals
Chemotaxis
A process where tiny bacteria can move away from light
Phototaxis
Single-celled organisms reproduce by first duplicating their DNA, then dividing it equally as the cell prepares to divide to form two new cells; many multicellular organisms produce specialized reproductive cells that will form new individuals.
Reproduction
All living organisms exhibit a “fit” to their environment.
Adaptation
Organisms grow and develop according to specific instructions coded for by their genes.
Growth and development
Multiple regulatory mechanisms are needed to coordinate internal functions: transport of nutrients, response to stimuli, and coping with environmental stresses.
Regulation
Cells require appropriate conditions to function properly which are:
Proper temperature, pH, and concentrations of diverse chemicals
Organisms are able to maintain internal conditions within a narrow range almost constantly, despite environmental changes, through this process.
Homeostasis
A process where many organisms regulate their body temperature
Thermoregulation
All organisms use a source of energy for their metabolic activities.
Energy processing
It is the smallest and most fundamental unit of matter.
Atom
It is a chemical structure consisting of at least two atoms held together by a chemical bond.
Molecule
These are large biologically important molecules.
Macromolecules
Small combined units that form large molecules
Monomers
Membranes that surround aggregates of macromolecules
Organelles
The smallest fundamental unit of structure and function in living organisms
Cell
Single-celled organisms that lack organelles surrounded by a membrane and do not have nuclei surrounded by nuclear membranes
Prokaryotes
Cells that have membrane-bounded organelles and nuclei
Prokaryotes
Groups of smaller cells carrying out the same function
Tissues
Collections of tissues grouped together based on a common function
Organs
A higher level of organization that consists of functionally related organs
Organ system
Individual living entities
Organisms
Refer to single-celled prokaryotes and single-celled eukaryotes
Miroorganisms
Collective name of all the individuals of a species living within a specific area
Population
The set of populations inhabiting a particular area
Community
Consists of all the living things in a particular area together with abiotic, or non-living, parts of that environment such as nitrogen in the soil or rainwater
Ecosystem
The collection of all ecosystems, representing the zones of life on Earth
Biosphere
The source of diversity; a process of gradual change during which new species arise from older species
Evolution
Field of specialization of atoms and molecules
Chemistry
Field of specialization of cells
Molecular biology
Field of specialization of tissues
Cell biology
Field of specialization of organs, organ systems, organisms, and population
Physiology
Field of specialization of communities and ecosystems
Ecology
