
Introduction:
Positive feedback is a physiological phenomenon in which a change in the system’s internal condition generates a response in the same direction as the cause of the change. In other words, positive feedback intensifies a physiological condition.

Answer to Problem 1E
Solution:
The correct answer is option (e).
Explanation of Solution
Explanation/justification for the correct answer:
During childbirth, the uterus undergoes contractions in order to push the fetus out of the cervix. This is aided by the action of the hormone oxytocin. It is known that uterine contractions during parturition induce the production of oxytocin. Oxytocin functions to intensify these contractions and help the fetus to move out of the cervix with ease. Hence, oxytocin sets up a positive feedback loop by increasing the uterine contraction. So, the correct answer is option (e).
Explanation for the incorrect answer:
Option (a) states that in conditions of increased acidity suppresses the cells lining the stomach walls to produce more acid. This is an example of negative feedback as the response to the change is in reverse direction to the cause. So, this is an incorrect option.
Option (b) states that a rise in blood pressure Triggers the elimination of water in the urine, which reduces blood pressure. This is an example of negative feedback as the response to the change is in reverse direction to the cause. So, this is an incorrect answer.
Option (c) states that an risein the concentration of H+in blood causes an risein excretion in urine. This is a case of negative feedback as elimination in urine reduces the concentration of H+in blood. Hence this option is incorrect.
Option (d) states that an risein carbon dioxide concentration in the blood Triggers breathing, which increases the rate at which carbon dioxide is eliminated from the body. Elimination reduces the carbon dioxide concentration in blood hence it is negative feedback. So this option is incorrect.
Among the given options option (e) Contraction of the uterus push the fetus against the cervix that triggers the release of oxytocin in the bloodstream; oxytocin the Triggers stronger contraction of the uterus. is an example of positive feedback.
Want to see more full solutions like this?
Chapter 1 Solutions
EBK PRINCIPLES OF HUMAN PHYSIOLOGY
- Amino Acid Coclow TABle 3' Gly Phe Leu (G) (F) (L) 3- Val (V) Arg (R) Ser (S) Ala (A) Lys (K) CAG G Glu Asp (E) (D) Ser (S) CCCAGUCAGUCAGUCAG 0204 C U A G C Asn (N) G 4 A AGU C GU (5) AC C UGA A G5 C CUGACUGACUGACUGAC Thr (T) Met (M) lle £€ (1) U 4 G Tyr Σε (Y) U Cys (C) C A G Trp (W) 3' U C A Leu בוט His Pro (P) ££ (H) Gin (Q) Arg 흐름 (R) (L) Start Stop 8. Transcription and Translation Practice: (Video 10-1 and 10-2) A. Below is the sense strand of a DNA gene. Using the sense strand, create the antisense DNA strand and label the 5' and 3' ends. B. Use the antisense strand that you create in part A as a template to create the mRNA transcript of the gene and label the 5' and 3' ends. C. Translate the mRNA you produced in part B into the polypeptide sequence making sure to follow all the rules of translation. 5'-AGCATGACTAATAGTTGTTGAGCTGTC-3' (sense strand) 4arrow_forwardWhat is the structure and function of Eukaryotic cells, including their organelles? How are Eukaryotic cells different than Prokaryotic cells, in terms of evolution which form of the cell might have came first? How do Eukaryotic cells become malignant (cancerous)?arrow_forwardWhat are the roles of DNA and proteins inside of the cell? What are the building blocks or molecular components of the DNA and proteins? How are proteins produced within the cell? What connection is there between DNA, proteins, and the cell cycle? What is the relationship between DNA, proteins, and Cancer?arrow_forward
- please fill in the empty sports, thank you!arrow_forwardIn one paragraph show how atoms and they're structure are related to the structure of dna and proteins. Talk about what atoms are. what they're made of, why chemical bonding is important to DNA?arrow_forwardWhat are the structure and properties of atoms and chemical bonds (especially how they relate to DNA and proteins).arrow_forward
- The Sentinel Cell: Nature’s Answer to Cancer?arrow_forwardMolecular Biology Question You are working to characterize a novel protein in mice. Analysis shows that high levels of the primary transcript that codes for this protein are found in tissue from the brain, muscle, liver, and pancreas. However, an antibody that recognizes the C-terminal portion of the protein indicates that the protein is present in brain, muscle, and liver, but not in the pancreas. What is the most likely explanation for this result?arrow_forwardMolecular Biology Explain/discuss how “slow stop” and “quick/fast stop” mutants wereused to identify different protein involved in DNA replication in E. coli.arrow_forward
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education





