answer

watching

views

16 Feb 2019

What hypothesis was being tested with the Îformin strain?

What hypothesis was being tested with the Îformin strain?

Formin is required for the signal transduction pathway leading to shmoo formation.

Mating factor is required to start the signal transduction pathway leading to shmoo formation.

Phosphorylation of formin is required for the signal transduction pathway leading to shmoo formation.

Formin causes shmoo formation in mating yeast.

answer

watching

323

views

For unlimited access to Homework Help, a Homework+ subscription is required.

You have 0 free answers left.
Get unlimited access to 3.8 million step-by-step answers.

Get unlimited access

Already have an account? Log in

Keith LeannonLv2

18 Feb 2019

Unlock all answers

Get 1 free homework help answer.

Already have an account? Log in

Related questions

What benefit can human stem cells provide to individuals with agenetically determine immunodeficiency? How would the process work?Can individuals receive their own stem cells?
Fill in the blanks with the missing information about primaryand secondary lymphoid organs:

The ___________ is the site of T cell development andmaturation. The ________ is the site of B cell differentiation andhematopoesis.

The ___________ are the sites where immune responses are mountedto antigens in the lymph. The _____________ is where immuneresponses are mounted to antigens in the blood. The ___________ islymphoid tissue that responds to antigen in the digestive,respiratory, and urogenital systems. Epithelial cells lackingmicrovilli that transport the antigens to these tissues are knownas ________.
Describe the structure of the B-cell receptor (BCR). How is theBCR able to trigger a signal transduction pathway when itscytoplasmic tail is only 3 amino acids in length? Outline BCRsignal transduction from the point of antigen binding through theNF-ÎºB pathway. What is the result of signal transduction eventsfrom the BCR?
What is agammaglobulinemia? What enzyme is mutated in thesepatients and what is this enzymeâs function? What happens to peoplewith this disorder?
What is Lck and why is it important? What would happen to a Tcell if a mutation were introduced in Lck?
Define the following and give an example for each:
1. cytokine
2. interleukin
3. chemokine
4. chemoattractant

ochremouse799

QUESTION 1

Which of the following is an example of an extracellular signal molecule?

	a.	IP₃
	b.	cAMP
	c.	Insulin
	d.	Diacylglycerol

2 points

QUESTION 2

Nuclear hormone receptors _____

	a.	Bind to water soluble ligands
	b.	Activate second messengers
	c.	Regulate transcription in response to ligand binding
	d.	Are normally located on the plasma membrane

2 points

QUESTION 3

Which of the following does not occur when a receptor tyrosine kinase is bound by ligand?

	a.	Phosphorylation of the RTK
	b.	Cytoplasmic proteins bind the phosphorylated RTK
	c.	Dimerization of the RTK
	d.	The RTK binds to DNA to regulate transcription

2 points

QUESTION 4

Which of these is a logical signal-transduction pathway?

	a.	An intracellular receptor activates phospholipase C, which cleaves a membrane protein to form IP₃, which then activates the opening of an ER channel protein, which releases cyclic AMP into the cytoplasm, where it binds to an intracellular enzyme that carries out a response.
	b.	A G-protein-linked receptor activates G protein, which activates phospholipase C, which cleaves a membrane lipid to form IP₃, which binds to a calcium channel on the ER, which opens to release calcium ions into the cytoplasm, which bind to an intracellular enzyme that carries out a response.
	c.	An ion-channel receptor opens, allowing a steroid hormone to enter the cell; the steroid hormone then activates protein kinases that convert GTP to GDP, which binds to an intracellular enzyme that carries out a response.
	d.	A tyrosine-kinase receptor activates adenylyl cyclase, which activates phospholipase C, which converts ATP into cyclic AMP, which binds to an intracellular enzyme that carries out a response.

2 points

QUESTION 5

Which of the following is an example of signal amplification?

	a.	activation of an enzyme molecule
	b.	activation of a specific gene by a growth factor
	c.	Breakdown of many cAMP molecules
	d.	activation of 100 molecules by a single signal binding event

2 points

QUESTION 6

Consider a signal transduction pathway that utilizes cAMP as a second messenger to activate PKA (Protein Kinase A). Which of the following situations will result in the cellular response?

		The G protein releases GDP and binds to GTP
		The target protein (adenylyl cyclase) is inactive
		The regulatory subunits of PKA (Protein Kinase A) are bound to the catalytic subunits
		The appropriate G protein is bound to GDP

2 points

QUESTION 7

Which of the following is found in only some signal transduction pathways? [In other words, which is not found in all signal transduction pathways?]

		Receptor protein
		Extracellular signal molecule
		Intracellular signaling molecule
		Cellular response
		Effector protein

2 points

QUESTION 8

The enzyme that specifically catalyzes the conversion of ATP to cAMP is:

		Adenylyl phosphatase
		Adenylyl kinase
		Adenylyl dehydrogenase
		Adenylyl cyclase

2 points

QUESTION 9

If an animal cell suddenly lost the ability to produce GTP, what might happen to its signaling system?

		It would use ATP instead of GTP to activate and inactivate the G protein on the cytoplasmic side of the plasma membrane.
		It would not be able to activate and inactivate the G protein on the cytoplasmic side of the plasma membrane.
		It would employ a transduction pathway directly from an external messenger.
		It would be able to carry out reception and transduction but would not be able to respond to a signal.

2 points

QUESTION 10

A hormone signal is sent from the brain to other parts of the body via the bloodstream. Why do only certain cells respond to this signal?

		Hormones do not last long enough in the bloodstream to stimulate a cellular response
		Only cells that have a specific transcription factor gene will be able to respond to the signal
		Only cells in the immediate vicinity of the cell sending the signal will respond
		Only cells that have a receptor for the specific signal will be able to respond to it

cerisehedgehog846

a) You are given an assignment by your Ph.D. advisor to study a protein that is involved in the development of cancer. This protein functions in a pathway that governs whether a cell divides. The lab starts you with a profile of mutations in this gene that result in tumors forming. You notice that there are mutations in lots of sites that result in cancer, and no single mutation is the cause. The only significant pattern you see is that the mutations introduced always replace non-polar amino acids with polar or charged amino acids. Explain how this type of mutation might result in the phenotype observed. What does this suggest to you as a hypothesis about the function of the protein being studied? How could you test your hypothesis in the laboratory (in vitro)?

b) Another mutation in this protein is found, that is âtumor suppressorâ meaning that when this mutation occurs, other cancer-causing mutations are prevented from causing tumors to form. This mutation is only a single amino acid, and it is always the changing of tyrosine residue to a phenylalanine. Based on the protein function hypothesis you suggested above and the special importance of tyrosine in some signal transduction pathways, describe a hypothesis for why this mutation suppresses tumor formation.