Natural Selection

3. Mutations only happen once in about once in every ___ (#) copies of DNA.
5. helix ___ describes the shape of your DNA – it looks like a twisted ladder.
6. An ___ is an advantageous trait found in most of a population (or entire species) that helps them survive and reproduce
7. ___ is when parents produce many, many offspring at a time (ex: a single frog may lay thousands of eggs).
10. ___ selection is where nature (the environment) picks the traits that are the “best fit” and helps individuals survive and reproduce.
12. A ___ is a group of organisms that are the same species and live in the same place (eco level).
14. A ___ is a specific characteristic of an organism (ex: brown eyes or dark hair) – created by a single gene.
15. DNA is found in the ___ of cells (cell organelle).
18. ___ means “best fit” – a better able to survive – and (and most importantly) have lots of offspring.
19. Parent DNA is copied when cells ___ during reproduction.
20. ___ is a word that means babies/children.
22. Some mutations are ___ and make it easier for the organism to survive.
25. ___ means that individuals in a population are all unique – they have different genes, inherited traits, and/or mutations.
27. Overproduction naturally leads to ___ as offspring struggle for limited resources.
28. A ___ is a specific type of living thing (ex: black bear, grizzly bears, and polar bears).

1. Some mutations are ___ and make it harder for the organism to survive.
2. A ___ is a group of organisms that are the same species and live in the same place (eco level).
4. ___ mutations have no effect ___ - they do not make it harder or easier for the organism to survive.
8. ___ is the string-like structure that carries the instructions (the code) for how to make every cell in your body.
9. DNA is tightly packed into larger structures called ___.
11. ___ selection is where that humans chose the traits that will be passed from parents to offspring.
13. ___ describes traits that are passed down to individuals from their parents.
16. ___ means individuals that are “best fit” (better-adapted) to their environment are more likely to survive and reproduce.
17. A ___ is a specific part of a chromosome that is responsible for a specific trait.
21. A ___ is a mistake that is made while DNA is being copied to make new cells or offspring.
23. ___ is the study of genes (or DNA, chromosomes) and inherited traits.
24. Mutations are ___ - they happen by chance.
26. A ___ is a specific type of living thing (ex: black bear, grizzly bears, and polar bears).