Following statements regarding to the classes of genes that regulate floral development:

A.  Floral organ identity genes directly control floral identity. The proteins encoded by these genes are transcription factors that likely control the expression of other genes whose products are involved in the formation and/or function of floral organs.

B.  Cadastral genes act as spatial regulators of the floral organ identity genes by setting boundaries for their expression.

C.   Meristem identity genes are necessary for the initial induction of the organ identity genes. These genes are the positive regulators of floral organ identity.

D.  Cadastral genes act as negative regulators of the floral organ identity genes by inhibits their expression.

E.   Meristem identity genes are the negative regulators of floral organ identity genes.

Which of the above statements are true?

#Question id: 11996

#Unit 10. Ecological Principles

#Question id: 11997

#Unit 10. Ecological Principles

#Question id: 11998

#Unit 10. Ecological Principles

#Question id: 11999

#Unit 10. Ecological Principles

#Question id: 12000

#Unit 10. Ecological Principles

The graph below shows  the  growth  rates  of  populations  of  bacteria  that  have  evolved  for  many  generations  at different culture temperatures (25°C, 30°C, and 35°C). Each population grows over only a limited range of temperatures (its thermal niche), which are bounded by its critical thermal limits. Within this range, growth rate increases with temperature up to a maximal value and then declines rapidly with increasing temperature. Growth rates are known to be the major determinant of fitness for these bacteria.

Which of the following is true concerning the thermal dependence of growth rate   between 25°C and 30°C in these populations?

#Question id: 12001

#Unit 10. Ecological Principles

The  graph  below  shows  the  growth  rates  of  populations  of  bacteria  that  have  evolved  for  many  generations  at different culture temperatures (25°C, 30°C, and 35°C). Each population grows over only a limited range of temperatures (its thermal niche), which are bounded by its critical thermal limits. Within this range, growth rate increases with temperature up to a maximal value and then declines rapidly with increasing temperature. Growth rates are known to be the major determinant of fitness for these bacteria.

Which population has the highest fitness at 25°C ?