Introduction to Genetics (BIOL0003) Notes - Basic Mendelism
9 views 0 purchase
Course
Introduction to Genetics (BIOL0003)
Institution
University College London (UCL)
Explore the fundamental principles of genetics with these concise notes tailored for Year 1 students in the Introduction to Genetics (BIOL0003) module at University College London. This document focuses on the basic Mendelism chapter, covering essential concepts like basic Mendelism, Mendel's secon...
Basic Mendelism
Basic Mendelism
23000 genes
Charles Darwin – 1837
o Studied evolution
Family tree
Gregor Mendel
o Interested in inheritance
o Worked on the hermaphrodite pea flower
Hermaphrodite = flower is both male and female
Ovary – contains egg cells (female cells)
Stigma – contains pollen (male cells)
Can fertilise itself – egg and pollen from same flower can produce new flower
Brush stigma over ovary – to produce new flower
o
Mendel made crosses between them
st
o 1 experiment
P1 – crossed Yellow X Green (parental generation)
P1 = parental generation
F1 – cross produced All Yellow (first filial generation)
F1 = first filial generation = 1st son generation produced from parental cross
F2 – ratio of 3 Yellow to 1 Green
F2 = second filial generation
o Mendel’s interpretation of his 1st experiment
P1 – YY x GG
Make Y, or G, pollen and egg
F1 – All YG = yellow colour
Yellow is dominant to Green – hinds green effects
F2 – ratio of 3 Yellow to 1 Green (phenotypes)
1YY: 2YG: 1GG (genotypes)
Genetical terminology
o Gamete
Organism’s reproductive cells (sex cells)
Female gametes – egg cells
Male gametes – sperm / pollen
Produced by meiosis
Contains 1n number of chromosomes
, Basic Mendelism
o Zygote
Normal body cells
Produced in mitosis
Gamete + gamete = zygote
Contains 2n number of chromosomes
o Locus
Position of a gene in the genome that codes for a particular characteristic
o Allele
Different forms of a gene
o Dominant
Variation of a gene that will be expressed in the phenotype if at least 1 copy is present
o Recessive
Variation of a gene that will only be expressed in the phenotype if two copies are present
o Homozygote
An individual having two identical alleles of a particular gene
o Heterozygote
An individual having two different alleles of a particular gene
Pedigrees – diagram showing the biological relationships between an organism and its ancestors
o
Consanguineous marriage = mating between two people descended from the same ancestor
o E.g.
Brachydactyly with three generation dominant pedigree
o Huntington’s disease = dominant
Cannot skip generations
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller sujansathiendran. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $8.63. You're not tied to anything after your purchase.