Chapter 10 Flashcards
Why do scientists classify organisms?
- To identify species
- To predict characteristics
- To find evolutionary links between organisms
Why can’t organisms from different species reproduce?
They have an odd number of chromosomes meaning that meiosis and gamete production cannot take place because chromosomes cannot make full pairs
Species
A group of organisms that are able to produce fertile offspring
Why are common names like ‘bullfrog’ not helpful when naming organisms
They don’t provide information about common ancestors
Binomial Nomenclature
This is the way that we name organisms. The first part of a name indicates the genus and is called the generic name. The second part of a name indicates the species and is called the specific name
Five Kingdoms
- Prokaryote (unicellular)
- Protoctisa (unicellular eukaryote)
- Fungi (yeasts, mould and mushrooms)
- Plantae (Plants)
- Animalia (Animals)
Archaebacteria
These are bacteria’s that are able to live in extreme environments like thermal vents
Eubacteria
These are found in all environments
Phylogeny
Evolutionary Relationships between organisms
Phylogenetic Tree Diagram
Illustrates different species that have evolved from one common ancestor. Oldest species at the bottom and Newest would be near the top
Galapagos Islands
Birds with longer beaks were better suited and more likely to survive and reproduce. Natural Selection. This is proven through Charles Darwin’s and Alfred Wallace’s research
Evidence for Evolution
Palaeontology - the study of fossil records
Comparing biochemistry - comparing the chemical makeup of organisms
Types of Variation
Interspecific Variation - Variation between members of different species
Infraspecific Variation - Variation between organisms within a species
Causes of Variation
Genetic variation and natural variation within a species.
Environmental variation and how variation is determined by the environment
Discontinuous Variation
Variables that can only end up being one or the other, example is eye colour
Continuous Variation
A characteristic that can take any value within a range like height or mass
Standard Deviation
A measure of how spread out the data is
Adaptations
These are characteristics that increase an organisms chance of survival and reproductive
Three types of adaptations
Anatomical - Physical features which are both internal and external like camouflage and scales and spikes
Behavioural - The way in which an organism acts
Physiological - The processes that take place within an organism like antibiotic production and poison production
Convergent Evolution
When unrelated species begin to share similar traits
Analogous Structures
Structures that have adapted to perform the same function but come from different genetic origins
Natural Selection
Occurs when organisms are exposed to selection pressures that affect the survival. When organisms show variation, they may have more advantageous genes and therefore be able to survive and reproduce offspring
