exam 2- environment & development

Question 1

phenotype = ___ + ___

Answer 1

genotype + environment

Question 2

___ buffers a population/species as a whole against environmental change

Answer 2

plasticity

Question 3

3 diff ways environment alters phenotype:

Answer 3

1- direct activation of signaling pathways: physical contact, tension of receptor pathways at the cell surface to activate signal cascades
2- modification of genes: methylation of genes by environmental factors alters expression
3- indirect activation- NS triggers a hormone that then activates signals

Question 4

___ are a major mechanism used by organisms to allow environmental signals to regulate development

Answer 4

hormones

Question 5

hormonal regulation of grasshopper color

Answer 5

in low population densities- green, short wings, and no migration

in high population densities- brown, long wings, and migrate

Question 6

name 3 chemicals in the environment that can alter development

Answer 6

several highly persistent environmental estrogens
DDT (& DDE)
dioxin
PCP’s

Question 7

name 3 classes of chemicals in the environment that can alter development

Answer 7

endocrine disrupters
environmental estrogens
bisphenol A (BPA)

Question 8

how to examine environmental effects on development

Answer 8

1- control environment (lab setting)
2- control/examine the organism