This is known as the evolution of different species from a single or common ancestor.
It is responsible for much of the biological diversity that we see on Earth today.
What is SPECIATION.
100
Binary fission, which is a kind of asexual reproduction, results in this.
What is TWO ORGANISMS (usually bacteria) THAT ARE GENETICALLY IDENTICAL.
100
Brown eyes are an example of this kind of variation.
What is DISCRETE VARIATION.
100
Scientists (or breeders) can select desirable traits and genes in these two ways.
What is GENETIC ENGINEERING & SELECTIVE BREEDING (or artificial selection)
100
Scientists estimate that this percentage of all species that have ever lived on planet Earth no longer exist.
What is 99%.
200
The hibernation of a polar bear, or the migration of birds to warmer climates in the winter are both examples of this, which helps an organism to survive its environment.
What is BEHAVIOURAL ADAPTATION.
200
Plants are unique in that they are one of the few organisms that can reproduce in these ways.
What are SEXUALLY AND ASEXUALLY.
200
Any change to a DNA molecule is known as this. Most are harmless, but some can be beneficial or harmful.
What is A MUTATION.
200
One of the four statements in Darwin's Theory of Natural Selection states that within each species there is incredible this.
What is VARIATION (or differences).
200
Grizzly bears have been THIS from mexico and mainland USA.
What is EXTIRPATED.
300
A Diversity Index measures this.
What is THE TOTAL NUMBER OF DIFFERENT ORGANISMS IN AN AREA.
300
Bacterial conjugation is considered a primary form of sexual reproduction for this reason.
What is NO NEW ORGANISMS ARE PRODUCED. ONLY DNA IS EXCHANGED.
300
These are made up of strands of DNA, and are found in the nucleus of a cell.
What are CHROMOSOMES.
300
Many animals were 'domesticated' thousands of years ago for this reason.
What is THEY WERE USEFUL TO HUMANS IN SOME WAY.
300
Surprisingly, this human activity can cause entire species to go extinct - as was the case with the passenger pigeon and the woolly mammoth.
What is OVER-HUNTING.
400
A niche involves these two things.
What is WHERE AN ORGANISM LIVES AND WHAT IT DOES (or its role).
400
These are the terms used to describe the male and female (in that order) reproductive organs of a flowering plant.
What are the PISTIL AND STAMEN.
400
When human somatic cells undergo mitosis, the new cells that are formed end up with this number of chromosomes.
What is 46.
400
Many wheat varieties grown in Canada have been artificially selected in order to resist this.
What is COLD CLIMATE (or early frost).
400
These are three examples of how humans are taking steps to preserve the number of different species that exist on our planet.
What are ZOOS, SEED BANKS, and GLOBAL TREATIES (protected areas, reduced pollution, etc).
500
Organisms that have this kind of niche are said to suffer from the "trap of specialization".
What is A NARROW NICHE.
500
Internal fertilization offers these advantages over external fertilization.
What is SAFE, MOIST, CONTROLLED ENVIRONMENT FOR GAMETES TO MEET. NUTRIENTS FOR EMBRYO TO GROW.
500
Genetic engineering has allowed scientists to do this.
What is MOVE GENES/DNA FROM ONE CELL TO ANOTHER.
500
This theory provides an explanation for why the fittest, or best-adapted organisms in a species will survive and reproduce.
What is NATURAL SELECTION.
500
Although zoos retain biological diversity, many people are ethically opposed to keeping animals in them for this reason.