Comparative Biochemistry & Anatomy Flashcards
What is Comparative DNA?
A comparison of the base sequences on similar chromosomes of different species. The more similar the base pairs the more recent the common ancestor
What does a Recent Common Ancestor refer to?
The more similar the species is the more recent the common ancestor
What is a Phylogenetic Tree?
A geographical representation of an evolution to show how different groups diverged over time
What is DNA?
- Very large molecules made up of two strands of nucleotides that are joined by bonds between the bases. The two strands are twisted into a double helix
- It is a chemical that makes up genes and determines the type of proteins a cell can make
- All species have DNA, however sequence of bases varies between species
What does Junk DNA refer to?
Chromosomes contain some non coding sequences of bases in the DNA, these are referred to as ‘Junk DNA’ as they have no apparent function and appear to serve no purpose. The more closely related the species the more junk sequences in common
What is an Endogenous Retrovirus?
Sections of non coding DNA (non functional). It is a viral sequence that has become apart of an organisms genome. A retrovirus becomes endogenous if it inserts into a reproductive cell (gametes) All subsequent generations will have ERV in the same location on the same chromosome
What is Mitochondrial DNA (mtDNA)?
Small amount of DNA is located in the mitochondria of DNA. It is in the form of circular molecules. There are about 5-10 molecules in each mitochondrion. It has 37 genes essential for the mitochondrion to functionally normally 24 genes for making transfer RNA involved in protein synthesis and 13 genes necessary to make the enzymes for cellular respiration reactions
How is mitochondrial DNA inherited?
- Ova and sperm both have mitochondria, an egg has many 100’s where as the sperm only have about 100 just enough to provide energy for the sperm to swim
- Therefore mitochondrial DNA is only inherited from the mother
- Similarity between mtDNA of any two individuals can be used to provide an estimate of the closeness of their relationship through maternal ancestors, if mtDNA is identical then a sibling if very different their last common ancestor lived long ago
What is a Protein Sequence?
- Proteins consist of long chains of amino acids, some proteins may contain as few as 100 amino acids linked together in a precise sequence sequence determined by the DNA
- Animals of the same species have identical amino acid sequences in their proteins and those from different species have different amino acids or they are arranged in a different order
What is an Ubiquitous Protein?
Refers to finding / comparing the amino acid sequences in the proteins that are common in all species. The more closely the amino acid sequences match the more recent the common ancestor e.g. Cytochrome C
What is Bioinformatics?
The use of computers to describe the molecular components of living things. It can be used to trace evolution of a large number of organisms by measuring changes in their DNA
What is Annotation?
The identification of genes and biological features in a DNA sequence
What is Comparative Genomics?
Genome sequences of different species are compared, by comparing the sequence of human genome with genomes of other organisms researchers are able to identify regions of similarity and difference
What does Comparative Anatomy refer to?
Involves comparing the structural features of related organisms to determine the degree of similarity between them. Similarities suggest they have a common ancestor
What is Comparative Embroyology?
- Provides evidence for evolutionary change over time by comparing the early stages of an organism
- Closely related species go through similar stages of development, although adults may not resemble each other closely, the longer the embryo remains similar the more recent the common ancestor
