Biology
I was genuinely surprised to learn about the role of master control genes in the evolutionary process. I always thought (as many people do, I think) that the development of a new trait required a mutation in a gene. And, honestly, I could never figure out how enough mutations could occur to create such a vast array of living species (and of course I still don't understand that). But, it makes a little more sense to me that there are a few genes that control development which generate physical diversity even in the presence of similar genes. This is cool!
And, of course, this provides a different framework in which to consider the genetic similarity between humans and chimps. Even though our DNA is 98% the same, the master control genes in the 2% kick in to generate more physical differences between the species. Also, good to know!
- Q: Explain How Protein Synthesis Can Be Controlled At A Transcriptional Level In Prokaryotes
In prokaryotes, genes that encode enzymes of a metabolic pathway are usually clustered together on the chromosome in a region called an operon. A typical operon consists of regulatory sequences, like promoter, operator, terminator, and structural genes....
- Globin Clusters Are Formed By Duplication And Divergence
KEY TERMS:Nonallelic genes are two (or more) copies of the same gene that are present at different locations in the genome (contrasted with alleles which are copies of the same gene derived from different parents and present at the same location on the...
- The Y Chromosome Has Several Male-specific Genes
KEY CONCEPTS:The Y chromosome has ~60 genes that are expressed specifically in testis. The male-specific genes are present in multiple copies in repeated chromosomal segments. Gene conversion between multiple copies allows the active genes to be maintained...
- The Human Genome Has Fewer Genes Than Expected
KEY CONCEPTS:Only 1% of the human genome consists of coding regions. The exons comprise ~5% of each gene, so genes (exons plus introns) comprise ~25% of the genome. The human genome has 30,000-40,000 genes. ~60% of human genes are alternatively spliced....
- Genomes Can Be Mapped By Linkage, Restriction Cleavage, Or Dna Sequence
Defining the contents of a genome essentially means making a map. We can think about mapping genes and genomes at several levels of resolution:A genetic (or linkage) map identifies the distance between mutations in terms of recombination frequencies....
Biology
Week Two: Evo devo thoughts
I was genuinely surprised to learn about the role of master control genes in the evolutionary process. I always thought (as many people do, I think) that the development of a new trait required a mutation in a gene. And, honestly, I could never figure out how enough mutations could occur to create such a vast array of living species (and of course I still don't understand that). But, it makes a little more sense to me that there are a few genes that control development which generate physical diversity even in the presence of similar genes. This is cool!
And, of course, this provides a different framework in which to consider the genetic similarity between humans and chimps. Even though our DNA is 98% the same, the master control genes in the 2% kick in to generate more physical differences between the species. Also, good to know!
- Q: Explain How Protein Synthesis Can Be Controlled At A Transcriptional Level In Prokaryotes
In prokaryotes, genes that encode enzymes of a metabolic pathway are usually clustered together on the chromosome in a region called an operon. A typical operon consists of regulatory sequences, like promoter, operator, terminator, and structural genes....
- Globin Clusters Are Formed By Duplication And Divergence
KEY TERMS:Nonallelic genes are two (or more) copies of the same gene that are present at different locations in the genome (contrasted with alleles which are copies of the same gene derived from different parents and present at the same location on the...
- The Y Chromosome Has Several Male-specific Genes
KEY CONCEPTS:The Y chromosome has ~60 genes that are expressed specifically in testis. The male-specific genes are present in multiple copies in repeated chromosomal segments. Gene conversion between multiple copies allows the active genes to be maintained...
- The Human Genome Has Fewer Genes Than Expected
KEY CONCEPTS:Only 1% of the human genome consists of coding regions. The exons comprise ~5% of each gene, so genes (exons plus introns) comprise ~25% of the genome. The human genome has 30,000-40,000 genes. ~60% of human genes are alternatively spliced....
- Genomes Can Be Mapped By Linkage, Restriction Cleavage, Or Dna Sequence
Defining the contents of a genome essentially means making a map. We can think about mapping genes and genomes at several levels of resolution:A genetic (or linkage) map identifies the distance between mutations in terms of recombination frequencies....