B15: Genetic Engineering Flashcards
What experiment did Mendel do?
He crossbred different type of peas and found that characteristics were inherited in clear and predictable patterns.
When was behaviour of chromosomes during cell division observed?
19th century
When was the structure of DNA determined?
mid-20th century
What was Lamarck’s idea of where animals came from?
Every type of animal evolved from primitive worms and the change from worms to other organisms was caused by inheritance of characteristics.
What was Lamarck’s theory of evolution?
The way organisms behaved affected the features of their body, ‘use it or lose it’.
What were Darwin’s 3 main ideas?
- Individual organisms in a particular species show a wide range of variation per characteristic.
2.reproduction always gives more offspring than the environment can support.
3.when they breed, they pass on the characteristics that have let them survive to the next generation.
Why was Darwin’s theory of evolution by natural selection only gradually accepted?
- conflict with the widely held belief that god made all the plants and animals on earth
-insufficient evidence
-no mechanism for explaining variation and inheritance (genetics weren’t understood for another 50 years)
What did Alfred Russel Wallace do?
He independently proposed the theory of evolution, and then published joint writings with Darwin in 1858: “The Origin of Species”
New species arise as a result of: ???
_-isolation, where two populations of a species become separated
-genetic variation between the populations
-natural selection that operates differently on the two populations
-speciation, where the populations become so different that successful interbreeding isn’t possible
What is geographical isolation?
When two populations become physically isolated by a geographical feature e.g. new mountain range, river.
What is environmental isolation?
When the climate changes in one area where an organism lives but not in other areas, e.g. if the climate becomes warmer in one area, pants will flower at a different time of year.
What are fossils?
The remains of organisms from millions of years ago, found in ice, rocks and other places.
What can we learn from fossils?
-what an animal looks like
-what an animal could eat
-the DNA of an organism
Why is the fossil record incomplete?
-soft bodied organisms don’t leave a fossil trace
-the right conditions for fossil formation were rare
-there are many fossils still to be found
What is extinction?
The permanent loss of all the members of a species tend
What are things that cause extinction?
-new predators can wipe out prey animals quickly.
-new disease
-successful competition
Why have bacteria evolved rapidly?
They reproduce at a fast rate
What do mutations of bacterial pathogens produce?
New strains
Why do you get resistant bacteria?
Individual resistant bacteria survive and reproduce so the population of resistant bacteria increases.
how do we prevent more resistant strains of bacteria from appearing?
-don’t overuse antibiotics
-make sure patients finish their course of medicine every time
-restrict the agricultural use of antibiotics
What is a bacteria that has become resistant?
MRSA
How can we reduce deaths from antibiotic resistant bacteria?
-specific bacteria should be treated with specific antibiotics
-medical staff keep good hygiene
-isolate patients with antibiotic resistant bacteria
-hospital visitors should be hygienic in hospitals
The development of new antibiotics is ——- and —— and is ——— to keep up with the emergence of new resistant strains.
Costly and slow, unlikely
Who classified living things into group depending on their structures and characteristics?
Carl Linnaeus
How did Linnaeus classify organisms?
He classified them into kingdoms, phylum, class, order, family, genus and species
How are organisms named?
By the binomial system of genus and species
What are the 3 rules for writing scientific names?
- The first name is the name of the genus to which the organism belongs, written with a capital letter.
- The second name is the name of a species to which the organism belongs, written with a lower case letter.
- The two names are underlined when hand written or are in italics when printed.
What is a domain?
A higher level of classification above kingdoms.
What are the 3 domains?
Archaea: primitive forms of bacteria (contains archaebacteria)
Bacteria: bacteria (contains eubacteria)
Eukaryota: organisms that have cells that contain a nucleus enclosing genetic material (Protista, fungi, plants, animals)
What are the six kingdoms?
Archaebacteria, eubacteria, Protista,fungi,plants,animals
