Genetics summary – VU BMS 2020/2021
Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7th edition
Chapter 2 – Mendelian inheritance
1
, Genetics summary – VU BMS 2020/2021
Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7th edition
2.1: Mendel’s study of pea plants
- Mendel studied pea plants
- His work was ignored until after his death
Mendel chose pea plants as his experimental organism
- A cross/hybridization is when two distinct individuals
with different characteristics are bred to each other
offspring are hybrids
- He investigated the natural laws that govern plant
hybrids. There were several varieties.
- Gamete = haploid reproductive cells that fuse to form a
zygote. In plants: pollination event
o Sperm cells produced in pollen grains that form
in the anthers
o Egg cells produced in ovules that form in the
ovaries
o Pollen grain lands on the stigma stimulated
growth of a pollen tube sperm cells enter
stigma, migrate to ovule. Fertilization when a
sperm enters the micropyle, an opening in the
ovule wall
- Self-fertilization natural for pea plants
- Cross-fertilization between different plants pollen on
stigma. Removed pollen, obtained pollen from another
plant
Mendel studied seven characteristics that bred true
- Characters are general characteristics of an organism
- Trait/variant = used to describe the specific properties of a character
o Eye color = character, blue eye color = trait
- Breading true means that the trait does not vary in appearance from generation to
generation
- True-breeding line/true-breeding strain = a variety that continues to produce the same
trait after several generations of self-fertilization
2
Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7th edition
Chapter 2 – Mendelian inheritance
1
, Genetics summary – VU BMS 2020/2021
Simone Zweers
Reference: Brooker, Genetics: Analysis and prinicples, 7th edition
2.1: Mendel’s study of pea plants
- Mendel studied pea plants
- His work was ignored until after his death
Mendel chose pea plants as his experimental organism
- A cross/hybridization is when two distinct individuals
with different characteristics are bred to each other
offspring are hybrids
- He investigated the natural laws that govern plant
hybrids. There were several varieties.
- Gamete = haploid reproductive cells that fuse to form a
zygote. In plants: pollination event
o Sperm cells produced in pollen grains that form
in the anthers
o Egg cells produced in ovules that form in the
ovaries
o Pollen grain lands on the stigma stimulated
growth of a pollen tube sperm cells enter
stigma, migrate to ovule. Fertilization when a
sperm enters the micropyle, an opening in the
ovule wall
- Self-fertilization natural for pea plants
- Cross-fertilization between different plants pollen on
stigma. Removed pollen, obtained pollen from another
plant
Mendel studied seven characteristics that bred true
- Characters are general characteristics of an organism
- Trait/variant = used to describe the specific properties of a character
o Eye color = character, blue eye color = trait
- Breading true means that the trait does not vary in appearance from generation to
generation
- True-breeding line/true-breeding strain = a variety that continues to produce the same
trait after several generations of self-fertilization
2
