1. Colorado AgriScience Plant Science
Unit 4: Plant Reproduction & Genetics
Lesson 2: Sexual Reproduction in Plants

2. Sexual Reproduction Involves flowers, fruit, & seed
Sperm from male flower fuses w/the ovum of the female plant
Results in recombination of DNA
Results in genetically unique individual
Allows plants to adapt & evolve to environmental change

3. Pollination
Transfer of pollen from the male to the female part of the plant(s)
How pollination occurs
Self-Pollination
Pollen from a plant pollinates a flower on the same plant
Cross-Pollination
Pollen from a plant pollinates a flower on a different plant

5. Fertilization
Necessary in flowering plants in order for a seed to develop
Double Fertilization
Unique to plants
Two sperm nuclei involved in fertilization
1st fertilization occurs when one sperm fuses with the egg creating a zygote
2nd fertilization occurs when the 2nd sperm nucleolus fuses with the two nuclei in the embryo sac
Results in the formation of the endosperm

6. Fertilization
Hybrid
Fertilization occurring from parents that are genetically different
Advantages
Best traits of each parent is expressed
Results in Hybrid Vigor
Increased growth, drought resistance, or insect resistance is possible

7. Fertilization & Genetics
Genetic information is stored in every cell of the plant in DNA
Segments of DNA, called genes, establish the code for plant appearance and traits
Genes are arranged into a set of chromosomes

8. Fertilization & Genetics
Diploid
Normal sets of cells containing two chromosomes
Haploid
Sex cells contain one chromosome
When fertilization occurs, the single sets of chromosomes are combined into the double set, one from each parent
Results in traits from each parent to be passed on to offspring.