3.1 Flashcards
classification (31 cards)
define biodiversity
a measure of variety of living organisms and their genetic differences
what is taxonomy
describing, classifying and naming living organisms
what is morphology
the study of the form and structure of organisms
what are analogous features
features that look similar or have similar function but are not from the same biological origin
what are homologous structures
structures that genuinely show common ancestry
what is the order of the taxonomy groups
domain
kingdom
phylum
class
order
family
genus
species
what are archaebacteria
ancient bacteria thought to be the oldest form of living organism
what are the 4 eukaryotic kingdoms
Protoctista
fungi
plantae
animalia
what is the morphological species model
a species is defined based solely on the appearance if the organism observed
what is sexual dimorphism
when there is a big difference between the appearance of the male & female of a species
define species
a group of closely related organisms that are all capable of producing fertile offspring
what is a limitation of the definition of species
plants frequently interbreed with similar species to form fertile offspring
define DNA sequencing
the process by which the base sequences if a genome of an organism is worked out
what is DNA profiling
the process by which the non-coding areas of DNA are analyzed to identify patterns
state an issue with classification based solely on appearance
enteral conditions can result in major differences in appearance of individuals of the same species
state 2 issues with finding common ancestors through DNA analysis on fossils
- DNA starts to degrade immediately after death
- the rate at which different parts of DNA mutates can vary (when dating ancestors)
what is gel electrophoresis
a method of separating fragments of protein or nucleic acids based on their electrical charge and size
explain the steps involved in gel electrophoresis
wells are filled with solution containing DNA fragments in a buffering solution
an electrical current is passed through the apparatus and the gel moves towards the positive anode
the fragments move at different rates depending on their mass and charge
once it is complete it is placed under uv light to show the pattern so that the different bands can be identified
how are DNA fragments cut and prepared for gel electrophoresis
cut into fragments via restriction endonuclease then added to gel containing dye which binds to the fragments in the gel and will fluoresce when placed under uv light
how is the DNA stopped from running off the gel
a dye is added to the fragment solutions that does not bind to the DNA but moves through the gel slightly faster than the DNA so that the current can be switched off before it runs off the gel
what charge does DNA have and why
negative charge due to the phosphate groups
how are the DNA fragments viewed after gel electrophoresis
Ninhydrin is added to the gel after electrophoresis has taken place
it reacts with the amino acids and show up as purple patches
define endosymbionts
an organism that lives inside the cells or the body of another organism
explain the endosymbiotic theory for mitochondria and chloroplasts
cells engulf photosynthetic organism/aerobic prokaryote as food
by chance in some cells they are not digested which gives them as advantage and allows them to grow more rapidly so it becomes a permanent feature and they are passed on during reproduction
