
Concept explainers
To analyze:
The variations in Po2 (in units of mmHg) in a typical open-close-fluttering cycle. Also explain the estimated mm Hg Po2 in the atmosphere and inside the tubes of trachea in all the three given experiments shown in figure B. Here, 1 kPa (kilopascal) = 7.5 mm Hg.
Given information:
The microscopic plastic tubes were inserted into the tracheae of the pupae of Attacus atlas moths by the researchers to study the tracheal function in the moths. The microtubes were attached to the sensors for recording the rate of CO2 that was released from the tracheae and also the intratracheal concentrations of O2.
The pupae were placed in the chambers by the researchers and the normal atmospheric levels of the gases were maintained. Researchers then recorded the behavior of spiracles, rate of CO2 release, and O2 concentrations in the tracheae. The results are shown in figure A.
In order to examine the spiracles performance in the different atmospheric conditions and their effects on the rate of CO2 release and O2 concentrations, pupae were exposed to the different levels of atmospheric O2. The levels of the release of CO2 and O2 concentrations were calculated during the fluttering stage as shown in the figure B.
Introduction:
The insectys have a unique mechanism of air exchange in their bodies. The respiratory system of the insects consists of the tracheae that is responsible for the gaseous exchange in and out of tissues. There are spiracles present that guards the trachea. They are valve-like and either remains open, closed, or in a fluttering state.

Explanation of Solution
Intratracheal partial pressure of O2 during the open phase of the spiracles in the tracheae as shown in the figure is 20.4 kPa.
If 1 kPa = 7.5mm Hg, then, Po2 during the open phase will be,7.5*20.4 = 153 mm Hg.
During the closed phase, Po2 decreases to 4–5 kPa.
If 1 kPa = 7.5mm Hg, then, PO2 during the closed phase will be,7.5*5 = 37.5 mm Hg.
During the fluttering phase, if the oxygen concentration is changed as shown in figure B, the PO2 will be calculated as
Case1, If 1 kPa = 7.5mm Hg, 7.5*6.4 = 48 mm Hg.
Case2, If 1 kPa = 7.5mm Hg, 7.5*21.2 = 159 mm Hg.
Case3, If 1 kPa = 7.5mm Hg, 7.5*40.2 = 301.5 mm Hg.
Thus, it can be concluded that the changes in approximate mm Hg of PO2 in a typical open-close fluttering cycle are 153 mm Hg and 7.5 mm Hg during the open and closed phases, respectively. Also, in the tubes of the trachea, in all the three given cases, the pressure was 48 mm Hg, 159 mm Hg, and 301.5 mm Hg, respectively.
Want to see more full solutions like this?
Chapter 48 Solutions
Life: The Science of Biology
- You have identified a new species of a Gram-positive bacteria. You would like to screen their genome for all proteins that are covalently linked to the cell wall. You have annotated the genome, so that you identified all the promoters, operons, and genes sequences within the operons. Using these features, what would you screen for to identify a set of candidates for proteins covalently linked to the bacterial cell wall.arrow_forwardBelow is a diagram from a genomic locus of a bacterial genome. Each arrow represents a coding region, and the arrowheads indicate its orientation in the genome. The numbers are randomly assigned. Draw the following features on the diagram, and explain your rationale for each feature: 10 12 合會會會會長 6 a) Expected transcriptions, based on known properties of bacterial genes and operons. How many proteins are encoded in each of the transcripts? b) Location of promoters (include rationale) c) Location of transcriptional terminators (include rationale) d) Locations of Shine-Dalgarno sequences (include rationale)arrow_forwardSample excuse letter in school class for the reasons of headaches and dysmenorrhea caused by menstrual cyclearrow_forward
- How do the muscles on the foot work to balance on an ice skate, specifically the triangle of balance and how does it change when balancing on an ice skate? (Refer to anatomy, be specific)arrow_forwardWhich of the following is NOT an example of passive immunization? A. Administration of tetanus toxoid B. Administration of hepatitis B immunoglobulin C. Administration of rabies immunoglobulin D. Transfer of antibodies via plasma therapyarrow_forwardTranscription and Translation 1. What is the main function of transcription and translation? (2 marks) 2. How is transcription different in eukaryotic and prokaryotic cells? (2 marks) 3. Explain the difference between pre-mRNA and post-transcript mRNA. (2 marks) 4. What is the function of the following: (4 marks) i. the cap ii. spliceosome iii. Poly A tail iv. termination sequence 5. What are advantages to the wobble feature of the genetic code? (2 marks) 6. Explain the difference between the: (3 marks) i. A site & P site ii. codon & anticodon iii. gene expression and gene regulation 7. Explain how the stop codon allows for termination. (1 mark) 8. In your own words, summarize the process of translation. (2 marks)arrow_forward
- In this activity you will research performance enhancers that affect the endocrine system or nervous system. You will submit a 1 page paper on one performance enhancer of your choice. Be sure to include: the specific reason for use the alleged results on improving performance how it works how it affect homeostasis and improves performance any side-effects of this substancearrow_forwardNeurons and Reflexes 1. Describe the function of the: a) dendrite b) axon c) cell body d) myelin sheath e) nodes of Ranvier f) Schwann cells g) motor neuron, interneuron and sensory neuron 2. List some simple reflexes. Explain why babies are born with simple reflexes. What are they and why are they necessary. 3. Explain why you only feel pain after a few seconds when you touch something very hot but you have already pulled your hand away. 4. What part of the brain receives sensory information? What part of the brain directs you to move your hand away? 5. In your own words describe how the axon fires.arrow_forwardMutations Here is your template DNA strand: CTT TTA TAG TAG ATA CCA CAA AGG 1. Write out the complementary mRNA that matches the DNA above. 2. Write the anticodons and the amino acid sequence. 3. Change the nucleotide in position #15 to C. 4. What type of mutation is this? 5. Repeat steps 1 & 2. 6. How has this change affected the amino acid sequence? 7. Now remove nucleotides 13 through 15. 8. Repeat steps 1 & 2. 9. What type of mutation is this? 0. Do all mutations result in a change in the amino acid sequence? 1. Are all mutations considered bad? 2. The above sequence codes for a genetic disorder called cystic fibrosis (CF). 3. When A is changed to G in position #15, the person does not have CF. When T is changed to C in position #14, the person has the disorder. How could this have originated?arrow_forward
- hoose a scientist(s) and research their contribution to our derstanding of DNA structure or replication. Write a one page port and include: their research where they studied and the time period in which they worked their experiments and results the contribution to our understanding of DNA cientists Watson & Crickarrow_forwardhoose a scientist(s) and research their contribution to our derstanding of DNA structure or replication. Write a one page port and include: their research where they studied and the time period in which they worked their experiments and results the contribution to our understanding of DNA cientists Watson & Crickarrow_forward7. Aerobic respiration of a protein that breaks down into 12 molecules of malic acid. Assume there is no other carbon source and no acetyl-CoA. NADH FADH2 OP ATP SLP ATP Total ATP Show your work using dimensional analysis here: 3arrow_forward
- Human Physiology: From Cells to Systems (MindTap ...BiologyISBN:9781285866932Author:Lauralee SherwoodPublisher:Cengage Learning
- Case Studies In Health Information ManagementBiologyISBN:9781337676908Author:SCHNERINGPublisher:CengageCardiopulmonary Anatomy & PhysiologyBiologyISBN:9781337794909Author:Des Jardins, Terry.Publisher:Cengage Learning,

