GCU BIO 319: LATEST A+ QUESTIONS AND ANSWERS
GUIDE FOR ULTIMATE SUCCESS
Define Genetics
The study of heredity and the variation of inherited characteristics.
Why study heredity and variation?
Organizing principle of life, thus a foundational concept in biology
Important for domestication and breeding of animals and plants
How did Mendel studied heredity systemically?
Crossed true-breeding pea plants and observed inheritance patterns of the seven traits
Genes
Determine traits (Morphology, Physiology, Behavior etc.)
The basic units of heredity
Genetic material must meet four criteria...
1. Information: contains information to construct entire organism
2. Transmission: during reproduction, passed from parents to offspring
3. Replication: copied with each cell division
4. Variation: varies in ways that can account for known phenotypic differences within each species
Carl Nageli and August Weismann
Proposed that a chemical substance within living cells is responsible for the transmission of traits from
parents to offspring
Chromosome Theory of Inheritance
Experimentation by many demonstrated that chromosomes are the carriers of the genetic material.
ID the hereditary molecule
Chromosomes are comprised of both nucleic acids and proteins.
Some genetic material from t he dead bacteria had been transferred to the living bacteria.
Provided the living bacteria with a new trait
add pic slide 14
DNA is the hereditary material
1940s: known that DNA, RNA, proteins and carbohydrates are major components of living cells.
Add pic
Resistance from the scientific community
, Hershey believed that the complicated structure of proteins made than more likely to be the carriers of
genetic information.
In 1952, he and his research technician (Chase) set out to prove this.
DNA is the genetic material of bacteriophage
- phage coat composed entirely of protein
- DNA inside the capsid head
-bacteriophage are viruses that infect bacteria
Alfred Hershey, Max Delbruck, and Salvador Luria won the Nobel Prize for their "discoveries concerning
the genetic structure of viruses"
add pic
Genes are the basic unit of heredity
Determine traits: Morphology, Physiology, Behavior
Segment of DNA that encodes a functional product (protein or RNA)
-"Central Dogma" articulated by Francis Crick in 1960's (also called gene expression)
Add pic
Genes influence traits at multiple levels
Molecular level
Cellular level
Organism level
Population level
Chromosomes
Structures within living cells that contain the genetic material
Prokaryotes (bacteria & archea): before the nucleus,
- no nucleus
- usually single circular chromosome
Prokaryotic Chromosome
Add pic
Eukaryotic cell
Add pic
Eukaryotic cells package DNA into chromatin (20K genes)
Nucleosome:
- the basic repeating unit of chromatin
- 1.8 turns (146bp) of DNA wrapped around a core of 8 histone proteins (octomer)
-- 2 each of: H2A, H2B, H3, and H4
- H1 histones bind in the linker region (~50bp) between nucleosomes (energetically favored)
Histones:
- small, highly basic proteins
GUIDE FOR ULTIMATE SUCCESS
Define Genetics
The study of heredity and the variation of inherited characteristics.
Why study heredity and variation?
Organizing principle of life, thus a foundational concept in biology
Important for domestication and breeding of animals and plants
How did Mendel studied heredity systemically?
Crossed true-breeding pea plants and observed inheritance patterns of the seven traits
Genes
Determine traits (Morphology, Physiology, Behavior etc.)
The basic units of heredity
Genetic material must meet four criteria...
1. Information: contains information to construct entire organism
2. Transmission: during reproduction, passed from parents to offspring
3. Replication: copied with each cell division
4. Variation: varies in ways that can account for known phenotypic differences within each species
Carl Nageli and August Weismann
Proposed that a chemical substance within living cells is responsible for the transmission of traits from
parents to offspring
Chromosome Theory of Inheritance
Experimentation by many demonstrated that chromosomes are the carriers of the genetic material.
ID the hereditary molecule
Chromosomes are comprised of both nucleic acids and proteins.
Some genetic material from t he dead bacteria had been transferred to the living bacteria.
Provided the living bacteria with a new trait
add pic slide 14
DNA is the hereditary material
1940s: known that DNA, RNA, proteins and carbohydrates are major components of living cells.
Add pic
Resistance from the scientific community
, Hershey believed that the complicated structure of proteins made than more likely to be the carriers of
genetic information.
In 1952, he and his research technician (Chase) set out to prove this.
DNA is the genetic material of bacteriophage
- phage coat composed entirely of protein
- DNA inside the capsid head
-bacteriophage are viruses that infect bacteria
Alfred Hershey, Max Delbruck, and Salvador Luria won the Nobel Prize for their "discoveries concerning
the genetic structure of viruses"
add pic
Genes are the basic unit of heredity
Determine traits: Morphology, Physiology, Behavior
Segment of DNA that encodes a functional product (protein or RNA)
-"Central Dogma" articulated by Francis Crick in 1960's (also called gene expression)
Add pic
Genes influence traits at multiple levels
Molecular level
Cellular level
Organism level
Population level
Chromosomes
Structures within living cells that contain the genetic material
Prokaryotes (bacteria & archea): before the nucleus,
- no nucleus
- usually single circular chromosome
Prokaryotic Chromosome
Add pic
Eukaryotic cell
Add pic
Eukaryotic cells package DNA into chromatin (20K genes)
Nucleosome:
- the basic repeating unit of chromatin
- 1.8 turns (146bp) of DNA wrapped around a core of 8 histone proteins (octomer)
-- 2 each of: H2A, H2B, H3, and H4
- H1 histones bind in the linker region (~50bp) between nucleosomes (energetically favored)
Histones:
- small, highly basic proteins
