Slide 1
Living organisms are distinguished by their ability to reproduce their own kind
Genetics is the scientific study of heredity and variation
Heredity is the transmission of traits from one generation to the next
Variation is demonstrated by the differences in appearance that offspring show from parents and siblings
Slide 2
Fig. 13-1
Slide 3
Concept 13.1: Offspring acquire genes from parents by inheriting chromosomes
In a literal sense, children do not inherit particular physical traits from their parents
It is genes that are actually inherited
Slide 4
Genes are the units of heredity, and are made up of segments of DNA
Genes are passed to the next generation through reproductive cells called gametes (sperm and eggs)
Each gene has a specific location called a locus on a certain chromosome
Most DNA is packaged into chromosomes
One set of chromosomes is inherited from each parent
Slide 5
In asexual reproduction, one parent produces genetically identical offspring by mitosis
A clone is a group of genetically identical individuals from the same parent
In sexual reproduction, two parents give rise to offspring that have unique combinations of genes inherited from the two parents
Video: Hydra Budding
Slide 6
Fig. 13-2
(a) Hydra
(b) Redwoods
Parent
Bud
0.5 mm
Slide 7
Fig. 13-2a
(a) Hydra
0.5 mm
Bud
Parent
Slide 8
Fig. 13-2b
(b) Redwoods
Slide 9
Concept 13.2: Fertilization and meiosis alternate in sexual life cycles
A life cycle is the generation-to-generation sequence of stages in the reproductive history of an organism
Slide 10
Human somatic cells (any cell other than a gamete) have 23 pairs of chromosomes
A karyotype is an ordered display of the pairs of chromosomes from a cell
The two chromosomes in each pair are called homologous chromosomes, or homologs