Adaptation and inheritance Flashcards
What are characteristics inherited from?
Genetic material stored in the nucleus of cells
How much DNA do we inherit from each parent?
Half from our mother and half from our father
What does DNA contain?
All the information needed to make an organism
What are chromosomes?
Long strands of DNA
What are sections of DNA that produce characteristics called?
Genes
Who worked together to produce a model of the structure of DNA?
Watson, Crick, Franklin, and Wilkins
How many chromosomes does a sperm contain?
23 chromosomes
How many chromosomes does an egg contain?
23 chromosomes
What happens during fertilization?
The genetic material joins together
How many chromosomes does each nucleus in an embryo contain?
46 chromosomes
What causes variation in organisms within a species?
Differences in their genes
What is natural selection?
The process where organisms with useful characteristics survive and reproduce
What does ‘survival of the fittest’ refer to?
Those better adapted to their environment are more likely to survive
What happens to successful genes over generations?
They are passed on to the offspring
What leads to the extinction of a species?
When there are no more individuals of that species left anywhere in the world
What do adaptations help an organism do?
Survive and reproduce
Give an example of an adaptation.
The cheetah’s speed as a predator
What do animals compete for?
Food, water, space, and mates
What do plants compete for?
Light, water, space, and minerals
What are some factors leading to extinction?
Destruction of habitat, new diseases, new predators, increased competition
What is environmental variation?
Characteristics affected by both inherited and environmental factors
What is the difference between discontinuous and continuous variation?
Discontinuous can only result in certain values; continuous can take any value within a range
How should discontinuous variation be plotted?
On a bar chart
How should continuous variation be plotted?
On a histogram
