1. Chapter 5 Outline
Heredity

2. Section 1 – Mendel and his Peas
Heredity – Passing of traits from parents to offspring
Dominant traits – The trait that appears
Recessive traits – The traits that seem to recede into the background
Genes – Segments of DNA that carry heredity instructions and are passed from parent to offspring: located on the chromosomes
Alleles – Different forms of a gene
Genotype – The inherited combination of alleles
Phenotype – An organism’s appearance
Probability – The mathematical chance that an event will occur

3. Mendel was born in 1822 in Heinzendorf, Austria
Mendel was born in 1822 in Heinzendorf, Austria. He was a monk and conducted his experiments in the monastery gardens.
Pollination – during pollination pollen from the anthers (male) is transferred to the stigma (female). Fertilization occurs when a sperm from the pollen travels through the stigma and enters the egg in an ovule.

4. Self Pollinating – plants that are self – pollinating contain both male and female reproductive strustures.
This means pollen of one flower can fertilize the eggs of the same flower or of another flower on the same plant.

5. True-Breeding plants
When a true-breeding plant self pollinates it will always produce offspring with the same trait the parent plant has. During cross-pollination the anthers of one plant are removed so the plant can’t self –pollinate that way you know exactly what pollen fertilized the plant. Punnett squares are the method of determining trait probability

7. Section 2 – Meiosis
Sex cells – An egg or sperm; a sex cell carries half the number of chromosomes found in other body cells
Homologous Chromosomes – chromosomes with matching information
Meiosis – produces new cells with half the usual number of chromosomes (sex cells)
Sex Chromosomes – Carry genes that determine whether the offspring is male or female

8. Sexual reproduction - two parent cells come together to form a new organism: used in most multicellular organisms
Asexual reproduction – one parent cell makes a copy of itself to form a new organism: most cells in your body as well as most unicellular organisms reproduce this way

9. Most normal human body cells contain 46 chromosomes (23 pairs) Each pair contains one chromosome donated by the mother and one donated by the father. These pair are the homologous chromosomes
Sex cells contain 23 chromosomes: male sex cells are sperm: female sex cells are eggs: each contains only one of the chromosomes from the homologous pairs
Genes are located on the chromosomes
Meiosis produces sex cells (egg and sperm) Human females have two X chromosomes and males have one X and one Y chromosome