Final Exam Flashcards Preview

Biology > Final Exam > Flashcards

Flashcards in Final Exam Deck (42):
1

What is phenotype plasticity?

the capacity for marked variation in the phenotype as a result of environment influences on the genotype during development

2

What is a phenotype?

the physical characterisitics of an organism

3

what is a genotype?

the genetic code of an organism (contained in its DNA) that carries the information necessary to produce an organisms physical characteristics

4

Phenotype plasticity is caused by?

Changes in DNA expression due to DNA methylation that alters transcription, or changes in protein function due to post-translational modification

5

DNA methylation can influence the __________ of organisms across generations

characterisitcs

6

Transcription is what?

the process of making a RNA copy of the information contained by DNA in the nucleus

7

Translation is what?

the process by which ribosomes in the rough endoplasmic reticulum use the information contained in RNA to make proteins

8

What are the four responses of individuals to a dynamic enviornment?

Behavioral responses
Physiological responses
Immune responses
Development responses

9

T or F: Individuals in a population vary

True

10

How much of an individual's variability is heritable?

At least some

11

What is genetic polymorphism?

the co-occurence (within the same population) of two or more forms (i.e. alleles) of a gene that code for different phenotypes

12

populations produce more offspring than are necessary to ________

replace the existing population

13

There is variation in the __________ individuals reproduce

number of offspring

14

This variation in number of offspring produced is partially dependent on the interaction between the _________ of the individual and its ________

phenotype; environment

15

The interaction between the phenotype of individuals and the environment can result in ________ with which alleles occur in the population

changes in the frequency

16

Ultimately, organisms appear adapted to their current environment because they have been shaped by ___________ through time

similar environments
Also known as natural selection

17

If some genotypes result in phenotypes that are more likely to survive than others, why do we see genetic polymorphism? Why havent all but the best genotypes disappeared?

1.) There is no selective advantage to either genotype
2.) There are spatial gradients (or patches) of selective forces within the environment that favor different genotypes
3.) There are cyclical fluctuations in the environment that alternately favor different genotypes
4.) heterozygotes have superior fitness

18

Random genetic variation and natural selection can result in _________

speciation

19

What is speciation?

the process by which different populations of a species
a.) occupy slightly different habitats
b.) accumulate genetic differences due to random chance and differential natural selection that overcomes the homogenizing effects of migration between populations
c.) ultimately become reproductively isolated from each other

20

What are the different categories of speciation?

allopatric speciation
parapatric speciation
symptric speciation

21

What is allopatric speciation?

speciation that occurs when two populations become geographically isolated from each other
*traditional view of speciation

22

What is parapatric speciation?

speciation that occurs when two populations occupy different geographic areas but have a narrow band of overlap between them

23

What is sympatric speciation?

speciation that occurs when subpopulations of a species are not geographically isolated but occupy slightly different microhabitats
*traditionally thought to be unlikely

24

What are life history traits?

fundamental characteristics of species that directly relate to survival and reproduction

25

Life history traits reflect what?

the reality that organisms must partition limited energy and resources among activity, growth, and development, and reproduction

26

Why must we understand life history?

its a major goal of ecology
important when managing our environment
a God-given responsibility

27

What are some important life history traits?

activity levels
growth and maintenance
reproducion

28

Attributes for growth and maintenance

age/size/stage survival probabilities
growth patterns
age at maturity
size at maturity

29

Attributes for reproduction?

frequency of reproduction
number of offspring
size of offspring
care of offspring

30

What is endothermy vs. ectothermy?

a case study of the trade-off between activity vs. growth and suvival

31

What is ectothermy?

having a body temperature determined primarily by environmental temperature (cold blooded)

32

What is endothermy?

using chemical reactions to generate heat for the purpose of maintaining a body temperature largely independent of environmental temperature (warm blooded)

33

What are some ectotherm advantages?

can be smaller/more elongated
more efficient at turning energy into growth or offspring
can survive on less food or more erratic food availability

34

What are some endotherm advantages?

can be active at a greater range of temperature
enhanced endurance

35

Life history traits are shaped by the ________

environment

36

Current reproduction hurts future reproduction if ____

there's intense competition
size based mortality in which smaller animals die

37

Current reproduction has little effect on future reproduction if _______

environment is benign with high survival
mortality is indiscriminant or size based mortality in which larger animals die

38

Fewer but larger offspring is favored if ______

there's intense competition
size based mortality in which smaller animals die

39

More but smaller offspring is favored if _____

the environment is benign with high survival
mortality is indiscriminant or size based mortality in which larger animals die

40

What theory describes the effect of the environment on the timing and number/size of offspring?

the r/K selection theory

41

What is r-selection?

occurs in unstable environments. Favor early reproduction and many, small offspring

42

what is K-selection?

occurs in stable environments. Favors delayed reproduction with few, large offspring.