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12 Mar 2018

In which structure does actual gas exchange take place in humans? What prevents the alveoli membranes from sticking together during exhalation? What is pulmonary surfactant? Why do premature babies often suffer from respiratory distress syndrome?

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15 Jan 2024

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12 Mar 2018

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Related questions

Help with Biology. Ive got some of the answers just need somehelp with others and see if what i have is good too.

Effect of enzyme concentration.

Ballon Diameter: (circumference):

TUBE 1: 15.5 cm

TUBE 2: 13.8 cm

TUBE 3: 8.8 cm

What is the enzyme in the experiment? What is the substrate?

Do you expect more enzyme activity if the substrateconcentration is increased or decreased? Explain. The moresubstrate you increase or decrease will cause the enzyme activityto increase or decrease up to a certain point. If you add to itthen it has more molecules to act upon. If you add enough substrateand all the enzymes are being used then it would reach a pointwhere there would be no further activity.

Effect of temperature.

Tube:

Refridgerator:

Temperature (0C): 16 degrees celcius

Ballon Diameter (cm): 17.1 cm

Room Temperature:

Temperature (0C): 28 degrees celcius

Ballon Diameter (cm): 17.1 cm

Boiling Water:

Temperature (0C): 83 degrees celcius

Ballon Diamter (cm): 6.9 cm

What is the enzyme in the experiment? What is the substrate?

How does temperature affect enzyme function? An increase intemperature results in more kinetic energy of the enzyme andsubstrate. It is more likely to collide with the enzyme for areaction to take place. To much heat however can cause the bondswhich holds the enzyme in the very specific shape to break and itwill no longer function (denatured).

What is the function of amylase? What does amylase do to starch?Amylase is a digestive enzyme that acts on starch in food, itbrakes down the starch into smaller carbohydrate molecules. Amylaseis made in two places the salivary glands in your mouth whichstarts the digestive process by breaking down the starch in foodsas you chew and convert that into maltose a smaller carbohydrate.The other place is in the pancrease which completes the digestivecarbohydrate, producing glueclose, a small molecule absorbed intothe blood and carried throughout the body.

Why did you wait 5 minutes before spraying with IKIsolution?

Saliva does not contain amylase until babies are about twomonths old. How could this affect digestion? (Hint: babies do noeat cereal until about 2 months old.) Amylase is needed fordigestion of starches and complex carbohydrates, this makes thefood for babies to not be digested and possibly pass right throughthe babies system and into a diaper. It can also lead to gas andconstipation for the baby. In the case of a high protein food itcould even cause problems with a babies underdeveloped kidneys.Babies are not usually able to eat solid foods until they are 4 to6 months old.

harlequinmacaw712

Background

Almost all animal and plant cells require oxygen and give off carbon dioxide. This is called gas exchange and it occurs by passive diffusion. Some animals do all or most of their gas exchange across their skin (for example amphibians) but they have very low metabolisms and use very little oxygen and get rid of very little carbon dioxide.

On the other hand humans (and other mammals) have very high metabolic requirements and we canât rely on gas exchange over the limited 1.5 to 2.0 square meters of our skin to get enough oxygen in and carbon dioxide out fast enough. Our gas exchange takes place across a very thin membrane in the Alveoli of the lung and the gas exchange surface in humans is estimated to be between 50 and 100 square meters, or between 25 and 67 times our skin surface area.

Our lungs provide a huge surface for gas exchange but they are a dead-end system. Once the oxygen in the lungs is used up it needs to be replenished and carbon dioxide builds up in the air spaces in the lungs and needs to get out. This is where the diaphragm and a few of the skeletal muscles become important. In its relaxed state the diaphragm is at its longest and the space in the thoracic cavity (and the lungs) is small. When the diaphragm contracts it shortens, which increases the volume of the thoracic cavity (and the lungs). The increase in size means the pressure is lower in the lungs than outside so air comes into the lungs (inhalation). As the diaphragm relaxes, the lungs decrease in size enough that the pressure inside the lungs is higher than the external air pressure so air comes out (exhalation).

Introduction

In this lab you will be building a model of a lung and experimenting with different ways to breath.

Supplies:

In the Lab Kit

One round 9" balloon (one lung, we donât need two for this)
medium-sized plastic bag large enough to fit over bottom end of bottle (diaphragm)
medium-size, thin rubber band

You supply

plastic 2-liter soda bottle with bottom cut off (thoracic cavity)

Tape (optional)

Directions:

1. Insert the balloon through the open bottom of a modified 2-liter soda bottle and up over the neck of the bottle. Pull the end of the balloon over the edges of the neck of the bottle. The balloon is held open by the neck of the bottle.

2. Place the plastic bag over the bottom (open) end of the 2-liter bottle and use the rubber band to hold it in place. This will serve as the diaphragm. To inflate the lung, blow into the balloon just before you fasten the rubber band. You can also wrap tape over the edges of the plastic bag to minimize air leaks

3. Grasp the bottom of the plastic bag and pull it down and push it up. Watch as the "lungs" (the balloon) expand and contract as you do this. The balloon has to change size because the air space between the balloon and bottle must remain constant. (Well, it would if the seal around the plastic bag and bottle were perfect).

You may block the "trachea" (the neck of the bottle) so that the air supply is cut off and watch as nothing happens when the "diaphragm" is pushed in and out.

This model isnât perfect. None of the joints are air tight as they would be in a real thoracic cavity. Pull the âdiaphragm down and watch the lungs expand . If you hold it in place, the lungs will collapse again over time. This is because of leaks and is not how real lungs work. Pushing the diaphragm in and pulling it out over and over does give you an idea of how lungs work. As the diaphragm tightens, contracts (pull down on the plastic bag) the lungs fill with air. As the diaphragm relaxes (push up on the plastic bag) air is expelled from the lungs .

There are several different ways we breath, i.e. expand our thoracic cavity so that our lungs can expand. You have just made a demonstration model of the diaphragm at work. You can also use your rib cage to expand and contract so that you can inhale and exhale. There are muscles between and around your ribcage which you can use to change the size of your thoracic cavity.

This is approximately what your model of a lung will look like.

Answer the questions on the Report Page

Report Page Name

1. Put a hand on your lower ribcage and try moving your ribs out and in. Does air also move in and out?

2. Someone with an upper back or neck injury may not have the options of using diaphragm or ribs to breath. They can learn to use the clavicle and the muscles attached to expand their thoracic cavity a small amount and breathe independently for short periods of time. Put your hand on you clavicle and try to raise and lower just that bone without using your diaphragm or your ribs. It isnât easy but you should be able to get a little air into and out of your lungs this way. How effective do you think this way of breathing is?

3. When you take a really deep breath you use all these muscle groups to help. Take a really deep breath and notice that your ribs expand, your lower abdomen comes out (a sign that the diaphragm has contracted) and your shoulders lift a little (the upper chest and clavicle are working). Now take a relaxed breath. Only your abdomen should go in and out. The movement of your abdomen is a result of the contracting diaphragm pushing on the contents of your âgutâ which forces your abdomen to push out.

Do you breath in or out when your diaphragm contracts?\

4. If a hole were poked in your thoracic wall (the wall of the pop bottle â the hole should be at least the diameter of a pencil)

a. what would happen when you tried to breath? (This is a pneumothorax).

b. Is the space between the balloon and plastic bottle still required to remain constant?

5. Would it be possible to live with a paralyzed diaphragm? Explain your answer.

fuchsiamuskrat152

Question #05: CV Integration and the Respiratory System The question for this week is as follows: Select a position on the question âhow good an athlete is the horseâ. Do you think the respiratory limitations of this specie (e.g. pulmonary hypertension, exercise induced pulmonary hemorrhage or EIPH) are expression of physiological compensation for a fit athlete, or are they manifestation of a system being ârun down to the ground in a very stressed athleteâ? Your answer must follow the outline shown in the introduction (sub-questions a, b, c, d, see above). Please notice that in this question both the structure and the function you are asked to select must be related to the EIPH syndrome. Hint: think on âthe circleâ.
a) Name the structure and the function on which your overall answer will be based? Be as specific as you can in delimiting the boundaries of your example (the most important part of your answer, since the following b, c, & d sub-questions are based on your answer to this first sub-question, a). Please notice that only 1 item is required (in your answer it should be labeled as âaâ). This answer should look like: âa.- My structure (S) is â¦. and its function (F) is â¦â. In same cases a second sentence might be needed. b) Why do you think that your structure and your function are related? Support your contention based on 3 lines of evidence based on the chemistry, physics, anatomy, or physiology involved in your example. Please notice that 3 items are required (answers should be labeled as âb1, b2, and b3â). One of this answers might look like: âb1.- If I do this experiment and measure this variable using this technique, this result will suggest that my S/F is correctâ. Please notice that MY question does not ask you to tell me what happens since this can be copy from any source, but it asked how do you know that your S/F relationship is true. c) Which are the levels of organization involved in your example (c1)? Cite events occurring at its main level of organization (c2) and indicate how they relate to the whole body level (c3). Please notice that 3 items are required (thus, answers should be labeled as âc1, c2, and c3â). These answers should look as follows: âc1.- molecularâ or any level of organization involved in your âaâ answer (S/F); âc2.- the first event is; the next even is; the middle event is; the next event is; the last event isâ. Five events distributed equidistant from each other is a good summary for the story line of the your S/F named in your âaâ answer. Finally, âc3.- at a whole individual level my S/F described in âaâ plays this roleâ. d) Which are the main feedback mechanisms involved in your example (cite at least two) (d1)? Expand on one of them (d2) and name 2 absolute requirement for that feedback to work (d3). Please notice that 3 items are required (answers should be labeled as âd1, d2, and d3â). These answers should look as follows: âd1.- an increase in this negative feedback ligand must decrease this variable under controlâ. This is how you NAME a negative feedback. For d1 you need to name two negative feedbacks; âd2.- the first event is; the next even is; the middle event is; the next event is; the last event isâ. Five events distributed equidistant from each other is a good summary for the most important negative feedback story line involved as a control of the your S/F named in your âaâ answer, that you named in d1; âd3.- this two components are absolutely necessary for the negative feedback described in d2 to be operational.