NAME ______ANSWER KEY___________________________________
CH. 15 STUDY GUIDE
DEFINITIONS:
1. Adaptation: A: INHERITED CHARACTERISTICS OF A SPECIES THAT DEVELOPS OVER TIME IN RESPONSE TO AN
ENVIRONMENTAL FACTOR, ENABLING THE SPECIES TO SURVIVE. EX: ARTIC FOX HAS A BETTER CAMOUFLAGE
FOR ICE THAN THE BROWN FOX
2. Allopatric speciation or geographic isolation: A: OCCURS WHEN A POPULATION DIVIDED BY A GEOGRAPHIC
BARRIER EVOLVES INTO TWO OR MORE POPULATIONS UNABLE TO INTERBREED.
3. Analogous structures: A: DOES NOT COME FROM A COMMON ANCESTOR, BUT THE STRUCTURE SERVES THE
SAME FUNCTION
4. Artificial selection: A: DARWIN’S TERM FOR THE SELECTIVE BREEDING OF ORGANISMS SELECTED FOR CERTAIN
TRAITS IN ORDER TO PRODUCE OFFSPRING HAVING THOSE TRAITS.
5. Behavioral isolation: A: THE EXPECTED BEHAVIOR IN A POPULATION THAT ATTRACTS A MATE. EX: HAPPY
FEET’S DANCE INSTEAD OF THE HEART SONG
6. Bottleneck: A: PROCESS IN WHICH A LARGE POPULATION DECLINES IN NUMBER, THEN REBOUNDS.
7. Camouflage: A: MORPHOLOGICAL ADAPTATIONS THAT ALLOW ORGANISMS TO BLEND INTO THEIR
SURROUNDINGS. WALKING STICK IN A TREE
8. Common descent: A: MANY SPECIES AROSE FROM A COMMON ANCESTOR.
9. Embryology: A: STUDY OF STRUCTURES OF ORGANISMS DURING EARLY STAGES OF DEVELOPMENT.
10. Evolution: A: HEREDITARY CHANGES IN GROUPS OF LIVING ORGANISMS OVER TIME.
11. Founder effect: A: RANDOM EFFECT THAT CAN OCCUR WHEN A SMALL POPULATION SETTLES IN AN AREA
SEPARATED FROM THE REST OF THE POPULATION AND INTERBREEDS, PRODUCING UNIQUE ALLELIC
VARIATIONS.
12. Genetic equilibrium: A: THAT THE ALLELE FREQUENCY IN A POPULATION WILL REMAIN CONSTANT IF 5
CONDITIONS ARE MET: NO GENETIC DRIFT, NO GENE FLOW, NO MUTATIONS, MATING IS RANDOM & THERE IS
NO NATURAL SELECTION.
13. Homologous structure: A: STRUCTURE COMES FROM A COMMON ANCESTOR AND THE SAME GENES, BUT
FUNCTION DIFFERENTLY
14. Mimicry: A: MORPHOLOGICAL ADAPTATION IN WHICH ONE SPECIES EVOLVES TO RESEMBLE ANOTHER SPECIES
FOR PROTECTION OR OTHER ADVANTAGES.
15. Natural selection: A: THEORY OF EVOLUTION DEVELOPED BY DARWIN, BASED ON 4 IDEAS: EXCESS
REPRODUCTION, VARIATIONS, INHERITANCE, AND THE ADVANTAGES OF SPECIFIC TRAITS IN AN ENVIRONMENT.
16. Sexual selection: A: CHANGE IN THE FREQUENCY OF A TRAIT BASED ON COMPETITION FOR A MATE.
17. Temporal isolation: A: OCCURS WHEN A POPULATION NO LONGER BREEDS AT THE SAME TIME.
18. Vestigial structures: A: A REDUCED FORM OF A STRUCTURE THAT IS NO LONGER USED
CHARLES DARWIN:
1. Explain Charles Darwin observation of the finches on the Galapagos Islands. A: THAT THE SHAPE OF THE BEAKS
ON THE FINCHES WERE DIFFERENT BECAUSE THE FOOD SOURCE WAS DIFFERENT ON THE DIFFERENT ISLANDS.
2. What was Darwin’s conclusion about how the finches changed on the Galapagos Islands? A: NATURAL
SELECTION WAS TAKING PLACE ON THE GALAPAGOS ISLANDS.
3. Give examples of analogous structures. A: BATS WING & INSECT WING – FUNCTIONS THE SAME BUT NOT
FROM A COMMON ANCESTOR.
4. Give examples of homologous structures. A: BAT’S WING & HUMAN ARM – FUNCTION DIFFERENTLY BUT CAME
FROM A COMMON ANCESTOR.
5. Give examples of vestigial structures. A: APPENDIX IN HUMANS; PELVIS IN WHALES
GRAPHS:
1. What type of graph is “A”? DIRECTIONAL
SELECTION
2. Explain what is being selected against in
graph “A”. SMALL BEAKS
3. What type of graph is “B”? STABILIZING
SELECTION
4. Explain what is being selected for in graph B.
AVERAGE SIZE BODY MASS
5. What type of graph is “C”? DISRUPTIVE
SELECTION
6. Explain what is being selected against in graph C. AVERAGE SIZE BEAKS
REVIEW QUESTIONS:
1. Explain transcription. PROCESS OF USING DNA TO CREATE MRNA IN THE NUCLEUS, AND EDITING MRNA
BY REMOVING THE INTROS & PUTTING THE EXONS BACK TOGETHER
2. Explain translation. MRNA GOES TO RRNA WITH TRNA READING MRNA & BRINGING IN THE CORRECT
AMINO ACIDS TO CREATE A POLYPEPTIDE CHAIN, WHICH FOLDS INTO A WORKING PROTEIN.
3. Explain a codon. 3 BASE NUCLEOTIDE SEQUENCE
4. Label the nucleotide structure to the right:
C: NITROGENOUS
BASE
A: PHOSPHATE
B: SUGAR