There are statement are given regarding the Plant pathogens groups   

a. derive energy from living cells, found on living plant have complex nutrition and do not kill host plants rapidly

b. derive energy from killed cells; they invade and kill plant tissue rapidly and then live saprotrophically on the dead remains

c. initially invading cells that are maintained alive prior to a transition to a necrotrophic life style in which nutrients are obtained from killing host cells

Choose which of the following is correctly defining the groups

#Question id: 11549

#Unit 7. System Physiology – Animal

If a biochemist discovers a new molecule, which of the following pieces of data would allow her to draw the conclusion that the molecule is a steroid hormone?

I) The molecule is lipid soluble.

II) The molecule is derived from a series of steps beginning with cholesterol.

III) The molecule acts at a target tissue some distance from where it is produced.

IV) The molecule uses a transport protein when in an aqueous solution such as blood.

#Question id: 11550

#Unit 7. System Physiology – Animal

Which of the following are similar in structure to cholesterol?

I) estradiol

II) insulin

III) glucocorticoids

IV) testosterone

V) antidiuretic hormone

#Question id: 11551

#Unit 7. System Physiology – Animal

Polypeptides can have which of the following types of effects?

I) autocrine

II) paracrine

III) endocrine

#Question id: 11552

#Unit 7. System Physiology – Animal

Which of the following are properties of steroid hormones?

I) Steroid hormones are lipid soluble and easily cross the phospholipid bilayer.

II) Steroid hormones usually exert their effects on target cells through membrane receptor proteins.

III) Steroid hormones act on cells close to where they were produced.

IV) Steroid hormones regulate gene transcription by binding to intracellular receptor proteins.

#Question id: 11553

#Unit 7. System Physiology – Animal

Tadpoles must undergo a major metamorphosis to become frogs. This change includes reabsorption of the tail, growth of limbs, calcification of the skeleton, increase in rhodopsin in the eye, development of lungs, change in hemoglobin structure, and reformation of the gut from the long gut of an herbivore to the short gut of a carnivore. Amazingly, all of these changes are induced by thyroxine. What is the most likely explanation for such a wide array of effects of thyroxine?

#Question id: 11554

#Unit 7. System Physiology – Animal

What happens in a cell when adenylyl cyclase is activated?