Adaptions and DNA Flashcards
(21 cards)
What is meant by the word “population”?
All the members of a single species that live in a habitat
Which of the following do plants not compete for?
Plants do not compete for food.
Why are polar bears white?
To camouflage them so their prey cannot see them
who discovered DNA?
Rosalind franklin ands watson and crick
Who produced the first X-ray pictures of DNA?
franklin
Which of these is smallest?
gene
Where are chromosomes found?
in the nucleas
Which two scientists discovered the shape of DNA?
watson and crick
what shape is dna?
double helix
How many chromosomes do normal body cells have?
23 pairs
How many chromosomes do sperm and eggs have?
23 chromosomes
What is the definition of a gene?
A section of DNA that gives a characteristic
How many genes do we have?
23
What are chromosomes?
Chromosomes are long coiled up lengths of DNA .
Can you get variation within a species?
Yes - plants or animals with inherited genes can even have different characteristics.
What two things can cause characteristic features?
Genes- if they are inherited
environment - surroundings
How can scientists help to manatin biodiversity?
Scientists can store the genes of different species in gene banks so that scientists might be able to create new members of extinct species in the future. They can also prevent the structure of habitats.
What are the two different classes of variation?
Continuous variation - meaning a feature can vary over a range of values.
Discontinuous - meaning can only take ceartain values.
What is a habitat?
An area where an organism lives.
Give the meaning of endangered.
At risk of becoming extinct
Explain why a change in the environment could lead to a species becoming extinct?
If the environment changes they may become less well adapted. So an organism may find it harder to compete for the recources it needs to survive and reproduce. If this happens to the whole species it could become extinct.
