Bio 305 - Hereditary

Theory of Epigenesis (William Harvey)

Structures such as body organs are not initially present in the early embryo and are formed later

Theory of Preformation

The fertilized egg contains a complete miniature adult called a humunculus

The Cell Theory (Schleiden and Schwann 1830)

All organisms are composed of basic structural units called cells

The Origin of Species (Darwin)

descent with modification, natural selection, theory of evolution

Descent with modification

Existing species arose from other ancestral species

Natural selection

The mechanism for evolutionary change

Theory of evolution

Independently proposed by Alfred Russel Wallace

Mendel’s ideas

traits are passed from generation to generation

transmission of genetic information from parents to offspring

chromosomes are copied and distributed resulting in two daughter cells who each reveive a diploid set

mitosis

chromosomes are copied and distributed resulting in gametes that receive only haploid (half the number of chromosomes)

meiosis

homologous chromosomes

a pair of matched chromosomes, one inherited from each parent, that have the same size, shape, and genes at the same locations but may have different versions (alleles) of those genes

chromosomal theory of inheritance

inherited traits are controlled by genes residing on chromosomes

genes are transmitted through?

gametes

alleles

the source of genetic variation produced by mutations

structure of DNA

antiparallel, double stranded helix, made of nucleotides

monomer is

a nucleotide consisting of a sugar (deoxyribose), bonded to a phosphate, also bonded to the bases adenine, cytosine, guanine, and thymine

structure of RNA

single-stranded, uracil in place of thymine, sugar in RNA nucleotides is ribose

central dogma

DNA → transcription → RNA → translation → protein