Exam 1 flashcards
genes
basic units of biological information
heredity
the way genes transmit traits from parents to offspring
genome
all the genes you possess
genetics
the science of heresity
Gregor Mendel (1822-1884)
Augustinian monk and expert plant breeder, discovered the basic principles of genetics in the mid-nineteenth century
artificial selection
only genetic practice was selective breeding of domesticated plants and animals with desirable characteristics
Two errors in genetics that are misleading
- one parent contributes most to offspring’s inherited features (male)
- blended inheritance, the idea that parental traits become mixed and forever changed in the offspring
What did Mendel do differently from those before him?
- chose the garden pea as his experimental organism (Pisum sativum)
- examined the inheritance of clear-cut alternative states of particular traits
- collected and perpetuated lines of peas that bred true
- made reciprocal crosses
- worked with large numbers of plants, counted all offspring, subjected his findings to numerical analysis, and then compared his results with predictions based on his models
- was brilliant practical expreimentalist
self-fertilization (selfing)
both egg and pollen come from the same plant/flower
cross-fertilize (cross)
mendel removed the male sex organs from the flowers of one plant and brushed the pollen from the other plant on to the femal organs of the first plant
continuous traits
opposite of discrete traits (height and skin color in humans) they show intermediate forms
pure-breeding (true-breeding)
produce offspring carrying specific parental characteristics that remain constant from generation to generation (inbred)
antagonistic pairs
constant but mutually exclusive alternatives (purple vs. white or yellow vs. green)
hybrids
offspring of genetically dissimilar parents, he cross-fertilized pairs of plants
