Natural Selection Flashcards
(20 cards)
DNA
Deoxyribonucleic acid, a molecule that is present in all living cells and that contains the information that determines the traits that a living thing inherits and needs to live.
Nucleotide
In a nucleic-acid chain, a sub-unit that consists of a sugar, a phosphate, and a nitrogenous base.
Chargaff’s Rules
State that DNA from any cell of all organisms should have a 1:1 ratio (base Pair Rule) of pyrimidine and purine bases and, more specifically, that the amount of guanine is equal to cytosine and the amount of adenine is equal to thymine.
Watson and Crick
Watson and Crick definition. The two twentieth-century biologists (James D. Watson of the United States and Francis H. C. Crick of England ) who discovered the double helix of DNA.
Rosalind Franklin
An English chemist and X-ray crystallographer who made contributions to the understanding of the molecular structures of DNA, RNA, viruses, coal, and graphite.
Mutations
A change in the nucleotide-base sequence of a gene or DNA molecules.
Adaptation
A characteristic that improves an individual’s ability to survive and reproduce in a particular environment.
Species
a group of organisms that are closely related and can mate to produce fertile offspring.
Evolution
The process in which inherited characteristics within a population change over generations such that new species sometimes arise.
Fossils
The remains or physical evidence of an organism preserved by geological processes
Fossil Record
A historical sequence of life indicated by fossils found in layers of the Earth’s crust.
Charles Darwin
An English naturalist, geologist and biologist, best known for his contributions to the science of evolution.
Trait
A genetically determined characteristic.
Selective Breeding
The human practice of breeding animals or plants that have certain desired characteristics.
Natural Selection
The process by which individuals that are better adapted to their environment survive and reproduce more successfully than less well adapted individuals do; a theory to explain the mechanism of evolution.
Generation Time
The period between the birth of one generation and the birth of the next generation.
Speciation
The formation of new species as a result of evolution.
Primates
A type of mammal characterized by opposable thumbs and binocular vision.
Hominid
A type or primate characterized by bipedalism, relatively long lower limbs, and lack of a tail; examples include humans and their ancestors.
Homo sapiens
The species of hominids that includes modern humans and their closest ancestors and that first appeared about 100,000 to 150,000 years ago.
