science Flashcards
DNA
deoxyribonucleic acid, a self-replicating material present in nearly all living organisms as the main constituent of chromosomes. It is the carrier of genetic information.
nucleotide
in a nucleic-acid chain, a subunit that consists of a sugar a phosphate and a nitrogenous base.
Chargaff’s Rules
Any cell should have a 1:1 ratio the amount of guanine should equal cytosine
Watson and Crick
concluded that dna looks like a long twisted ladder.
Rosalind Franklin
franklin used X-Ray diffraction to make images of dna that helped reveal the structure of dna.
mutations
a change in the nitrogenous base sequence of a gene or DNA molecule.
adaptations
a change or the process of change by which an organism or species becomes better suited to its environment.
species
a group of organisms that are closely related and can mate to produce fertile offspring
evalution
the process in which inherited characteristics within a population change over generations such that new species sometimes arise
fossiles
the remains or physical evidence of a past creature.
fossil record
a historical sequence of life indicated by fossils found in layers of the earths crust.
Charles Darwin
founder of evolution
trait
a genetically determined characteristic
selective breeding
the human practice of breeding animals or plants that have a certain desired characteristic
natural selection
the process by which individuals that are better adapted to their environment survive and reproduce more successfully then less adapted
