TLS Online TPP Program

#Question id: 8687


Your professor wants you to construct a phylogenetic tree of orchids. She gives you tissue from seven orchid species and one lily. What is the most likely reason she gave you the lily?

#Unit 9. Evolution & Diversity of Life Forms
  1. to serve as an outgroup
  2. to see if the lily is a cryptic orchid species
  3. to see if the lily and the orchids show all the same shared derived characters
  4. to demonstrate likely homoplasies
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TLS Online TPP Program

#Question id: 7162

#Unit 5. Developmental Biology

Is regeneration in Hydra similar to regeneration in vertebrates, or is it fundamentally different in some way?

TLS Online TPP Program

#Question id: 7163

#Unit 5. Developmental Biology

What statement is correct when comparing morphallaxis and epimorphosis?

TLS Online TPP Program

#Question id: 7164

#Unit 5. Developmental Biology

If an amphibian zygote is manipulated so that the first cleavage plane fails to divide the gray crescent, then ________.

TLS Online TPP Program

#Question id: 7165

#Unit 5. Developmental Biology

Embryonic induction, the influence of one group of cells on another group of cells, plays a critical role in embryonic development. In 1924, Hans Spemann and Hilde Mangold transplanted a piece of tissue that influences the formation of the notochord and neural tube, from the dorsal lip of an amphibian embryo to the ventral side of another amphibian embryo. If embryonic induction occurred, which of the following observations justifies the claim of embryonic induction?

TLS Online TPP Program

#Question id: 7166

#Unit 5. Developmental Biology

Just prior to the onset of gastrulation in an embryo, the "organizer" cells are specified. If you were to experimentally block the specification of these cells, what would you expect the result to be in the developing embryo?

TLS Online TPP Program

#Question id: 7167

#Unit 5. Developmental Biology

The following experiment is designed to study the role of several hormones in the regulation of metamorphosis in frogs.

Group #

Treatment

Days to Metamorphosis

1

Saline

30

2

Prolactin

> 100

3

TSH

15

4

Thyroxine

10

5

Corticosterone

30

6

Thyroxine + Corticosterone

5

7

Prolactin + TSH

30

8

Thyroid gland removed

> 100

These results suggest which of the following about prolactin (group 2 and group 7) at the dose tested?