classification Flashcards
what are the different molecular sequences
- DNA sequencing
- DNA hybridisation
- Protein sequence
what is DNA sequencing?
DNA is made up of 4 bases (adenine, guanine, cytosine and thymine), these bases give organisms their characteristics. The more similar the DNA sequence, the more closely related species are.
what is DNA hybridisation?
DNA is double-stranded, but when heated up it can denature into two strands. When it cools down again it attempts to line back up with a second strand. This DNA is linked to another organism stranded molecule, the more links between each strand the more closely related they are
what is protein sequencing
Refers to the chains of amino acids being compared between two organisms. The more similarities within the chains the more closely related the organisms are.
what are molecular clocks
Are sequence differences of both DNA and proteins over time. There is a relationship between the amount of time and the number of changes. This means a ratio can ve determined when two species last shared a common ancestor.
what are the main categories of characteristics
- physical
- reproductive
- genetic
what are the different physical characteristics
- macro or cellular level
- types of skeleton
- types of symmetry
- segmentation
what can physical classification occur at
Physical classification can occur at a macro level or a cellular level.
what are the types of skeletons
exoskeleton - external skeleton
endoskeleton internal skeleton
hydroskeleton - no skeleton
what is segmentation
Segmentation applies to invertebrates. It is the division into spreading sections.
what are the types of symmetry
bilateral symmetry - the division into two equal sides (left, right, up and down)
radial symmetry - the number of divisions as long as its cit through a central axis
what are the different reproductive methods
sexual reproduction - gametes from individuals
asexual reproduction - single organism reproduction
what are the different types of asexual reproduction
- fragmentation
- binary fission
- spores
- parthenogenesis
what is fragmentation
the splitting of an organism’s body which is regenerated into a whole organism
what is binary fission?
Refers to cell division which involves an organism duplicating its DNA and split it into 2 bodies
what are spores
releases of genetic material which can be activated later
what is parthenogenesis
It is a female-only reproduction that involves them producing embryos from an unfertilised egg
what is sexual reproduction
Is the mixing of gametes from two individuals. Some organisms lay eggs and some have live young.
What are genetic characteristics
DNA, RNA and protein sequences are all indicative of relatedness. The greater the similarity the more closely related organisms are
what is DNA
- deoxyribonucleic acid
- 4 bases (adenine, thymine, guanine, cytosine)
- These base sequences determine RNA sequences
what is RNA
- ribonucleic acid
- 4 bases (adenine, guanine, cytosine, uracil)
- these base sequence determines which amino acids join together to make proteins
what are proteins
- made up of long, folded sequences of amino acids
- essential for life
- changes are rare otherwise, this will result in death
what are the conventions of binomial nomenclature?
a binomial name consists of a generic and specific name. The generic name denotes the genus and the specific name is unique to a species.
define speciation
Refers to the formation of new species due to evolution. It refers to the splitting of a single evolutionary linage.
what is asexual reproduction
It does not involve the fusion of gametes or changes in the number of gametes. The offspring that arises will inherit the full set of genes of their single parent.
