Log in
Biology
1
answer
0
watching
76
views

Page 10 Bio 2050

A. How is colon cancer different from other gentic disease?

B. Where do the genes in a particular cell come from?

C. Do all cells in your body have the same genes present?

D. How do cells get their distinct features?

E. What is regulation of gene expression?

F. What is the genome?

Watch
1
answer
0
watching
76
views

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

Trinidad Tremblay
Trinidad TremblayLv2
29 Sep 2019

Unlock all answers

Get 1 free homework help answer.
Already have an account? Log in
Share

Related textbook solutions

Molecular Cell Biology
8 Edition,
Lodish
ISBN: 9781464183393
Biology: Science for Life with Physiology
6 Edition,
Belk
ISBN: 9780134555430
Concepts of Biology
OER Edition,
Openstax
ISBN: 9781938168116
Biology
2nd Edition, 2013
Openstax
ISBN: 9781947172517
Essentials of Biology
5 Edition,
Mader
ISBN: 9781259660269

Related questions

2. In eukaryotic cells, _________determine the amount of mRNA arising from a particular gene.

a. transcriptional-level controls

b. RNA processing-level controls

c. translational-level controls

d. replication-level controls

e. b and c

3. In eukaryotic cells, _________determine how a primary transcript is converted to mature mRNA

a. transcriptional-level controls

b. RNA processing-level controls

c. translational-level controls

d. replication-level controls

e. a and d

4. In eukaryotic cells, _________determine when a particular mRNA is actually used in protein synthesis.

a. transcriptional-level controls

b. RNA processing-level controls

c. translational-level controls

d. replication-level controls

e. None of the above because protein synthesis takes place immediately

5. Under what circumstances do cells selectively activate and suppress their genes?

a. at different stages of embryonic development

b. in different tissues

c. exposure to different types of stimuli

d. No such circumstances exist in nature—cells express all their genes throughout life.

e. a, b and c

6. Which statement about the control of gene expression is FALSE?

a. A single gene may be controlled by different transcription factors.

b. A single transcription factor may be necessary for the expression of different genes.

c. Each cell type has a characteristic pattern of gene transcription, which is determined by the particular complement of transcription factors contained in that cell. d. Expression of protein genes is primarily controlled in nucleoli

e. Control of gene transcription is complex and influenced by various circumstances.

7. What is thought to maintain X chromosome inactivation in females?

a. DNA acetylation

b. DNA methylation

c. RNA inactivation

d. Histone methylation

e. None of the above because both X chromosomes are active in females and males.

It was all over the news (March 29, 2018) that a new cancer “vaccine” was about to begin human trials after a 97% success rate in mouse trials against both blood cancers (lymphomas) and solid tumors such as breast and colon cancer. I will excerpt a description compiled from several scientific and news sources. Based on what we talked about in Bio 221, you should be able to understand this. Answer each of the questions about this exciting new “vaccine.” T cells are present in most tumors by infiltration. These include CTLA4-expressing Treg cells, as well as CD4- expressing TH cells and CD8-expressing cytotoxic T-lymphocytes. Once cancer is well established, the balance between these inputs is tipped toward immunosuppression. We found that a Toll-like receptor 9 (TLR9) ligand, CpG, induces the expression of OX40, an alternate costimulatory receptor, on CD4 T cells when it is injected into the tumor microenvironment. This is an indirect induction, in which CpG induces cytokine secretion by myeloid cells which in turn induces OX40 expression on T cells. Then OX40 can be activated using anti-OX40 antibodies, thereby activating TH cells in the tumor.

D. How do antibodies that recognize OX40 help to stimulate TH cells? (Hint: think about autoimmune diseases. There is one we didn’t talk about, called Graves’ disease, that you might want to look up, too.) What else is required for the TH cells to become activated?

E. How does all of this kill the cancer cells? What other cells in the tumor also must become activated? How?

F. How does this differ from the CAR-T cell therapy?

It was all over the news this morning (March 29, 2018) that a new cancer “vaccine” was about to begin human trials after a 97% success rate in mouse trials against both blood cancers (lymphomas) and solid tumors such as breast and colon cancer. I will excerpt a description compiled from several scientific and news sources. Based on what we talked about in Bio 221, you should be able to understand this. Answer each of the questions about this exciting new “vaccine.”

T cells are present in most tumors by infiltration. These include CTLA4-expressing Treg cells, as well as CD4- expressing TH cells and CD8-expressing cytotoxic T-lymphocytes. Once cancer is well established, the balance between these inputs is tipped toward immunosuppression. We found that a Toll-like receptor 9 (TLR9) ligand, CpG, induces the expression of OX40, an alternate costimulatory receptor, on CD4 T cells when it is injected into the tumor microenvironment. This is an indirect induction, in which CpG induces cytokine secretion by myeloid cells which in turn induces OX40 expression on T cells. Then OX40 can be activated using anti-OX40 antibodies, thereby activating TH cells in the tumor.

A. What is CTLA4 and how does it establish immunosuppression?

B. What is a costimulatory receptor, and why is an alternate one required here?

C. How does a TLR ligand such as CpG induce cytokine expression by myeloid cells? What myeloid cells are involved here?

D. How do antibodies that recognize OX40 help to stimulate TH cells? (Hint: think about autoimmune diseases. There is one we didn’t talk about, called Graves’ disease, that you might want to look up, too.) What else is required for the TH cells to become activated? E. How does all of this kill the cancer cells? What other cells in the tumor also must become activated? How? F. How does this differ from the CAR-T cell therapy?

Weekly leaderboard

Home
Homework Help 3,900,000
Biology 460,000
Start filling in the gaps now
Log in