10,886 Matching Annotations
  1. Apr 2021
    1. sent the different wavelengths/frequencies in different directions, all towards a screen

      Opens the beam like a fan by wavelength with the shortest wave lengths/highest frequency’s at one end and the longest wave lengths /lowest frequency’s at the other.

    2. up and down along the screen

      Along the range of wave lengths

    1. properties of waves

      various forms of electromagnetic radiation

    2. Scientists discovered much of what we know about the structure of the atom by observing the interaction of atoms with various forms of radiant, or transmitted, energy

    1. indefinite

      undefined

      hard to tell when

    2. carbonate species.

      line 23

    3. The overall

      line 16

    4. matter such

      line 11

    5. through decomposition.

      line 7

    6. carbonate species.

      what's the connection with species and cations/anions/carbonates

    7. leaving a net imbalance of positive charged species.

      hold up do these species eat these items or how do they connect

    8. positively charged cations

      so do positive species give off these positively charges byproducts?

    9. 5.5

      they're acidic babey

    10. “When a stress is applied to a system at equilibrium, the equilibrium shifts to relieve the stress.”

      I wish I could shift to relieve stress, I'd shift away from school and just work at Brewhouse forever. Who needs college amirite

    11. positive species

      is a positive species just a species that gives off positive charged elements or what?

    12. by the imbalance of positively charged species that exists in the oceans as opposed to negatively charged ones allowing an equilibrium reaction to occur between carbon dioxide and the ocean.

      once again, w h a t ?

    13. a solubility pump through achieving equilibrium in the direct air-to-sea exchange of carbon dioxide

      oh neat but also w h a t ?

    14. In oceans, the situation is somewhat more permanent as once a carbon molecule is dissolved

      yeah ocean acidification is killing shells of crustaceans and whatnot.

    15. plant matter back into carbon dioxide through decomposition.

      it also plays a part in the CO2 cycle by spitting out oxygen as a totally useless byproduct, but other living organisms like cows use it to breath and through cellular respiration their byproduct is CO2 so it's a never ending cycle.

    16. a quarter is drawn into land plants and the remaining quarter taken by the oceans.

      ocean acidification is being worsened by the amount of CO2 levels in the atmosphere but plants taking it in is just photosynthesis.

    17. sequestering

      s e q u e s t e r i n g

      to remove or isolate

    1. These interactions are side-to-side rather than the head-to-head interactions characteristic of σ orbitals.

      Sobre npx e npy

    2. Figure 11.5.5

      Figura importante!

    3. bondorder=numberofbondingelectrons−numberofantibondingelectrons2(11.5.4)

      Explicação de onde veio esse 1/2 da Ljubica

    4. lower in energy (more stable)

      Quando menor em energia, mais estável é!

    1. Events AAA and BBB are mutually exclusive (cannot both occur at once) if they have no elements in common.

      Events \(A\) and \(B\) are mutually exclusive (cannot both occur at once) if they have no elements in common.


      Events \(A\) and \(B\) are mutually exclusive if: $$P(A∩B)=0$$

    2. The complement of an event AAA in a sample space SSS, denoted AcAcA^c, is the collection of all outcomes in SSS that are not elements of the set AAA. It corresponds to negating any description in words of the event AAA.

      The complement of an event \(A\) in a sample space \(S\), denoted \(A^c\), is the collection of all outcomes in \(S\) that are not elements of the set \(A\). It corresponds to negating any description in words of the event \(A\).


      The complement of an event \(A\) consists of all outcomes of the experiment that do not result in event \(A\).

      Complement formula:

      $$P(A^c)=1-P(A)$$

    1. Colligative properties are the physical changes that result from adding solute to a solvent. Colligative Properties depend on how many solute particles are present as well as the solvent amount, but they do NOT depend on the type of solute particles, although do depend on the type of solvent.

      Colligative properties are the physical changes that result from adding solute to a solvent. Colligative Properties depend on how many solute particles are present as well as the solvent amount, but they do NOT depend on the type of solute particles, although do depend on the type of solvent.

    1. The dipole moment of a solvent, or of any covalent compound, is a microscopic property, meaning it is a property of the molecule of the compound

      dipole momment

    1. This line is incorrect. Multiplication does distribute over substraction as well eg: \(7 \times (3-4) ?= (7 \times 3) - (7 \times 4)\) $$ 7 \times (-1) ?= 21 - 28 $$ $$ -7 eq -7 $$

    1. membrane cell membrane nuclear membrane

      cytoplasm between cell membrane and nuclear membrane

      all membranes have similar structures

      membrane function varies from one organism to another different proteins and lipids

    1. solving P2=4π2GMr3P2=4π2GMr3\mathrm{P^2=\frac{4π^2GM}{r^3}} for the ratio r3P2

      Should this be, "... for M" rather than "r^3/p^2"?

    2. P2=4π2a3GM

      This derivation is only valid for circular orbits as mentioned above just under "Derivation of Kepler's Third Law". Although Kepler's third applies to elliptical orbits, I don't think you can replace radius with semi-major axis (5.6.22 -> 5.6.23). Maybe "a" in 5.6.23 is a typo?

    1. Smith was careful to nurture the image of the English as being strong and interested in trade for trade’s sake, rather than out of any need

      كان سميث حريصًا على رعاية صورة الإنجليز على أنهم أقوياء ومهتمون بالتجارة من أجل التجارة ، وليس بسبب أي حاجة

    1. Rule 7: cf(x)=f(x)cf(x)=f(x)cf(x ) = f(x) (for c>1c>1c > 1) stretched vertically. Rule 8: cf(x)=f(x)cf(x)=f(x)cf(x ) = f(x) (for c<1c<1c < 1) compressed vertically.

      Rule 7 : for c > 1 stretched vertically Rule 8 : for 0 < c < 1 compressed vertically Rule 9 : for c > 1 compressed horizontally Rule 10 : for 0 < c < 1 stretched horizontally

    1. The Dutch became the most important force in the spice trade under the aegis of the Dutch East India Company.

      أصبح الهولنديون القوة الأكثر أهمية في تجارة التوابل تحت رعاية شركة الهند الشرقية الهولندية.

    1. During the westward expansion of the United States, pioneers and the army often gave Native Americans blankets laced with smallpox germs in order to more quickly “civilize” the West.

      Intentional contagion of infection, also called voluntary contagion, conscious contagion, or intentional transmission is the act by which a human being deliberately infects another with a pathogen knowing that they will be infected.

    1. sodium carbonate

      sodium hydroxide

      turns triglycerides back into their sodium salts(soap molecules)

    2. chemical reactions

      a variety of

      esters can be hydrolysis in acids , bases, or specific lipase enzymes

      bases make soap in saponification

      triglycerides tallow and coconut oil

      today, hydrolyzed with water @ 700 lbs / in*2, or ~50 atm or 5000 kPa, @ 200 C

    3. physical properties fats oils clear, colorless, odorless

      color, taste, odor from lipid soluble substances

      color from carotene taste from diacetyl, and 3-hydroxy-2-butanone from bacteria in ripening cream

      fats oils lighter than water 0.8 g / cm^3

      poor conductors of heat and electricity therefore, great insulators

    4. fats oils FUNCTIONS energy, insulation, transport fat soluble vitamins through the blood TRIGLYCERIDES, TRIGLYCEROLS esters trihydroxy alcohol glycerol three fatty acids SIMPLE TRIGLYCERIDE, MIXED TRIGLYCERIDE glycerol's oh groups esterified same fatty acids simple triglyceride two or three fatty acids mixed triglyceride mixed triglycerides are naturally occurring

      fats, solid at 25 C oils. liquid at 25 C animal usually fats plant usually oils animal fats vegetable oils

      no single formula for triglycerides depends on plant or animal species depends on climate factors

      saturated and unsaturated term for food fats saturated fats and high cholesterol cholesterol intake leads to heart disease

  2. Mar 2021
    1. China and the USA than in any other country.

      Not surprisingly, 2 of the most populous nations , minus India where most are vegetarians. What about per capita?

    2. The immune system also becomes less adept at fighting off illness, and reproductive capacity starts to decline (Boundless, 2016).

      Evidence proves that Conscious Lifestyle habits like exercise and unconscious mind cognition slow down or speed up aging drastically.

    1. What are some factors that help explain these changes in living arrangements? First, early adults are postponing marriage or choosing not to marry or cohabitate. Lack of employment and lower wages have especially contributed to males residing with their parents. Men who are employed are less likely to live at home. Wages for young men (adjusting for inflation) have been falling since 1970 and correlate with the rise in young men living with their parents. The recent recession and recovery (2007-present) has also contributed to the increase in early adults living at home. College enrollments increased during the recession, which further increased early adults living at home. However, once early adults possess a college degree, they are more likely to establish their own households (Fry, 2016).

      Isn’t true that most woman are with older men too???

    1. Emerging adulthood is the age of possibilities. It is a time period of optimism as more 18 to 25 year-olds feel that they will someday get to where they want to be in life. Arnett (2000, 2006) suggests that this optimism is because these dreams have yet to be tested. For example, it is easier to believe that you will eventually find your soul mate when you have yet to have had a serious relationship. It may also be a chance to change directions, for those whose lives up to this point have been difficult. The experiences of children and teens are influenced by the choices and decisions of their parents. If the parents are dysfunctional, there is little a child can do about it. In emerging adulthood, people can move out and move on. They have the chance to transform their lives and move away from unhealthy environments. Even those whose lives were happier and more fulfilling as children, now have the opportunity in emerging adulthood to become independent and make decisions about the direction they would like their life to take.

      Isn’t that almost all of the lifespan? I feel like this science is limited quite significantly.

    2. p

      I at 40 something must still be an emerging adult. Thank GOOD

    3. Emerging adults change jobs, relationships, and residences more frequently than other age groups.

      This textbook tries hard to put folk in cookie cutters, but i definitely am unconventional. The science has me feeling as though I am “underdeveloped”, In a good way though.

    1. The fixed phase constant 𝜙ϕ\phi is new; it describes what the wave looks like at (𝑥=0,𝑡=0)(x=0,t=0)(x=0,t=0). The symbol ±±\pm asks us to choose +++ or −−-, which describes the direction that the wave travels.

      write this down along with up above of the y(x,t) position

    1. These stoichiometric factors can be used to compute the number of ammonia molecules produced from a given number of hydrogen molecules, or the number of hydrogen molecules required to produce a given number of ammonia molecules. Similar factors may be derived for any pair of substances in any chemical equation. Recall that a balanced chemical equation describes not only numbers of atoms/molecules but also numbers of moles of reactants and products.

      telling us what it can do and what to do.

    2. These quantitative relationships are known as the reaction’s stoichiometry, a term derived from the Greek words stoicheion (meaning “element”) and metron (meaning “measure”). In this module, the use of balanced chemical equations for various stoichiometric applications is explored.

      its telling us what the word "stoichiometry" means

    3. outline of the various computational steps associated with many stoichemetry calculations

    4. relating masses of reactants and products

    5. helpful information

    6. A balanced chemical equation provides a great deal of information in a very succinct format.

      helpeful info

    7. mass

      weight

    8. 3molCO21molC3H8(5.1.7)

      ratio

    9. C3H8+5O2→3CO2+4H2O

      beginning equation

    10. hydrogen and nitrogen:

      instead of pancakes a real equation

    11. two dozen

      coefficient

    12. 1 cup pancake mix, 3434\dfrac{3}{4} cup milk, and one egg.

      initial equation

    1. Χοληστερόλη -> ευκαρυωτες και βακτήρια χωρίς κυτταρική μεμβρανη

      Οπανοειδή -> Βακτηρια

      Εργοστερόλη -> μυκητες και πρωτοζωα

    2. Lipid Bilayer : Αποτελείται από χοληστερόλη και φωσφολιπιδια σε παρόμοια αναλογία κατά βαρος που έχουν αλληλεπιδρασει μη ομοιοπολικα (noncovalently),για να την σχηματίσουν.

    1. under a microscope 1,000 times more powerful

      under a microscope that is 1,000 times

    2. Although law is not normally considered a field related to chemistry

      it should read 'Criminal Law' to remove ambiguity & confusion.

    1. 𝐴AA is always positive.

      amplitude is always positive

    2. In most material waves we typically encounter, the "shape" of the disturbance stays the same over short travel distances.

      and changes further away from the initial disturbance

    1. With 100 pennies, we have 99 degrees of freedom for the mean. Although Table 4.4.34.4.3\PageIndex{3} does not include a value for t(0.05, 99), we can approximate its value by using the values for t(0.05, 60) and t(0.05, 100) and by assuming a linear change in its value. t(0.05,99)=t(0.05,60)−3940{t(0.05,60)−t(0.05,100})t(0.05,99)=t(0.05,60)−3940{t(0.05,60)−t(0.05,100})t(0.05, 99) = t(0.05, 60) - \frac {39} {40} \left\{ t(0.05, 60) - t(0.05, 100\} \right) \nonumber t(0.05,99)=2.000−3940{2.000−1.984}=1.9844t(0.05,99)=2.000−3940{2.000−1.984}=1.9844

      I'm not sure how to estimate t(.05, 99); could someone explain these functions please?

    1. The first page of the Workbook is the "Front Page (figure 4.54.5\PageIndex{5}) and on this you will post your answers and Copies of the three graphs (from the other pages of the workbook, which can be accessed via the tabs at the bottom of the page).

      test in public domain showing links do not highlight

    1. ent chemical reactions were considered to be unidirectional (Reactants → Products) and the percent yield was based on the complete consumption of the limiting reagent. It was pointed out the the percent yield would often be less than 100% and the following four reasons were discussed (section 4.3).

      test

    1. H3PO3(aq)  +  Ca(OH)2(aq)

      simple grammatic error, question doesn't reflect the ammonium found as reactants and products in the answer

    2. Ca(OH)2

      doesn't display state

    1. Ionic bond, also known as electrovalent bond, is a type of bond formed from the electrostatic attraction between oppositely charged ions in a chemical compound. These kinds of bonds occur mainly between a metallic and a non metallic atom.

      Ionic bond is a kind of bond formed by the electrostatic attraction between opposingly charged ions in a chemical compound, also known as an electrovalent bond. Such bonds exist mostly between a metallic and a non-metallic atom.

    1. And would it have been worth it, after all, After the cups, the marmalade, the tea, Among the porcelain, among some talk of you and me, Would it have been worth while, To have bitten off the matter with a smile, To have squeezed the universe into a ball To roll it towards some overwhelming question, To say: “I am Lazarus, come from the dead, Come back to tell you all, I shall tell you all” If one, settling a pillow by her head Should say: “That is not what I meant at all; That is not it, at all.”

      It seems as though he is feeling regret here, and rightfully so. He should have more confidence, bravery, and courage. You only live once. No?

    2. And indeed there will be time To wonder, “Do I dare?” and, “Do I dare?” Time to turn back and descend the stair, With a bald spot in the middle of my hair (They will say: “How his hair is growing thin!”) My morning coat, my collar mounting firmly to the chin, My necktie rich and modest, but asserted by a simple pin (They will say: “But how his arms and legs are thin!”) Do I dare Disturb the universe? In a minute there is time For decisions and revisions which a minute will reverse.

      This makes him sound so sad and pathetic. I don't mean that in a disparaging way, but merely in an observatory way.

    3. And indeed there will be time To wonder, “Do I dare?” and, “Do I dare?” Time to turn back and descend the stair, With a bald spot in the middle of my hair (They will say: “How his hair is growing thin!”) My morning coat, my collar mounting firmly to the chin, My necktie rich and modest, but asserted by a simple pin (They will say: “But how his arms and legs are thin!”) Do I dare Disturb the universe? In a minute there is time For decisions and revisions which a minute will reverse.

      This stanza is interesting because of its reference to aging. I think that it gives off eh assumption that what the person is experiencing is the opposite of beauty and admiration, which is normally displayed in a love song. Also, he is saying that time moves on but so do our bodies, in love songs someone might say that they will love someone forever, but in this line it is saying that does not last just like beauty. #goldenline

    4. No! I am not Prince Hamlet, nor was meant to be; Am an attendant lord, one that will do To swell a progress, start a scene or two, Advise the prince; no doubt, an easy tool, Deferential, glad to be of use, Politic, cautious, and meticulous; Full of high sentence, but a bit obtuse; At times, indeed, almost ridiculous Almost, at times, the Fool.

      I think the narrator of this poem is talking about lost loved or missed opportunities. Based on this line I think he means to convey that not all love is found and things fade as well as opportunities to express your feelings elegantly. #goldenline

    5. When the evening is spread out against the sky Like a patient etherized upon a table; Let us go, through certain half-deserted streets, The muttering retreats Of restless nights in one-night cheap hotels

      Right off the bat I can tell this isn't a conventional love poem because it uses language that wouldn't normally be considered romantic. I do like the wording however because it does give a certain unpleasant feeling.

    6. After the sunsets and the dooryards and the sprinkled streets,

      This line to me just has beautiful imagery. I simple love it’s simplicity and the instant imagery that it evokes once read.

    7. There will be time, there will be time To prepare a face to meet the faces that you meet;

      I like this line because it makes me curious to what he is referring to. At first I think he is referring to her having enough time to get ready and do her makeup for the night out but then it also makes me wonder if he means something more.

    8. When the evening is spread out against the sky Like a patient etherized upon a table;

      I really like this line because of the use of language the author choose. It really helps you see what the author is trying to say and describe to us the reader.

    9. Is it perfume from a dress That makes me so digress?

      I liked this line because such mundane things can sometimes lead us through profound trains of thought. Like with Dickinson's "There's a certain slant of Light" and how a beam of light made her think of death and religion, a whiff of perfume made this speaker think of his self worth and longing for connection and love.

    10. There will be time, there will be time To prepare a face to meet the faces that you meet;

      I liked this line because I interpreted it as he was preparing a persona to match the people he would be spending time with. Instead of just being himself, to make others like him he would prepare a "face" that's more likeable just for the validation of others.

    11. Do I dare Disturb the universe?

      This line struck me because it showed that the speaker thought so little of himself that merely making his existence known to the world is seen as him as a disturbance. He contemplates if his longing for connection is worth staining the earth with his identity.

    12. “That is not it at all, That is not what I meant, at all.”

      We often worry about a single choice before we even begin to thing about making it. It can eat us alive, the fear of making the wrong choice, but we'll get no where if we don't move at all. We lose both choices if we hesitate, if we worry over all the consequences before considering all of the positive aspects.

    13. I should have been a pair of ragged claws Scuttling across the floors of silent seas.

      This hit as the speaker is tired of the ennui and he was wishing he was a simple creature that lives on the bottom of the ocean, so he wouldn't be consumed by these kind of thoughts.

    14. (But in the lamplight, downed with light brown hair!)

      This is what I love about Eliot, he can mix whimsical with the serious, the silly with the profound.

    15. For I have known them all already, known them all: Have known the evenings, mornings, afternoons, I have measured out my life with coffee spoons;

      I feel here that the speaker knows his time is running out and he feels the passage of time. Maybe his life is pretty much the same day to day so that's why he says I have known them all already.

    16. To wonder, “Do I dare?” and, “Do I dare?”

      To me, this is the line that really soldifies my thought that this poem is about indecision. This question, "Do I dare? and "Do I dare?" It means that two different options can sometimes lead you to the same place, but you just have to make that leap, that choice.

    17. To wonder, “Do I dare?” and, “Do I dare?” Time to turn back and descend the stair, With a bald spot in the middle of my hair (They will say: “How his hair is growing thin!”)

      To me this poem is filled with melancholy and ennui, I feel like this is the speaker not living/enjoying the moment and thinking about when he is going to get older.

    18. I should have been a pair of ragged claws Scuttling across the floors of silent seas.

      In the poem, the main character is seen as a bad person on the out side. He notes earlier that people only notice how his hair is growing thin and he is extremely skinny. People around him do not treat him like he should be treated. In this line, I think he is saying that he might as well be the ugly monster on the inside and out. Then people would have a right to judge him.

    19. To wonder, “Do I dare?” and, “Do I dare?”

      Often times, there will be many occasions where someone will wonder if they should dare to do or try something. This line "Do I dare?" relates back to any reader because people often question their actions before completing them. In this poem, I wonder what he is considering doing.

    20. In the room the women come and go Talking of Michelangelo.

      This is the second time this line appears in the poem. This makes me wonder why it is used more than once. What is the reason for Michelangelo to be brought up twice. Also why is Talking capitalized.

    21. I should have been a pair of ragged claws Scuttling across the floors of silent seas.

      I feel in this line that he wishes he was the monster that other people make him out to be.

    22. Among the porcelain, among some talk of you and me,

      The porcelain I feel is symbolic of something that is both fragile and refined. This could symbolize a strained relationship; one that the narrator wants to maintain, but it takes a good deal of care to do so.

    23. No! I am not Prince Hamlet, nor was meant to be;

      I chose this line because I think it means that the narrator is not wanting to be a tyrant, but he has been cast into this role. Since Hamlet is a play about a Prince who is so focused on revenge that he ends up destroying everything around him.

    24. Am an attendant lord, one that will do To swell a progress, start a scene or two, Advise the prince; no doubt, an easy tool, Deferential, glad to be of use, Politic, cautious, and meticulous;

      Here the speaker tells how he is not important and is merely a tool for the important people. He acknowledges that it is his role in life to serve the important people and stay out of their way. He feels it is not his place to ask existential questions. He also feels that if he were to ask, he would be misunderstood.

    25. And I have seen the eternal Footman hold my coat, and snicker, And in short, I was afraid.

      From these lines I got the sense that the speaker has given up on trying to change himself and the world. He feels like the presence of death makes a fool of him and he accepts it. He allows the "eternal footman" to snicker at him and the speaker feels afraid but does not fight to change.

    26. Do I dare Disturb the universe?

      To me these lines are asking if one person has the bravery to try and change the universe. The speaker seems to feel hopeless and that he has no control over his own fate. He watches himself grow old. He knows that he is capable of changing how he views the world but he isn't sure if he is brave enough to.

    27. Till human voices wake us, and we drown.

      This was the most concerning line as it makes me believe that the author has fully accepted a death as he is. I feel as if I am missing something however, and that it cannot possibly be that simple.

    28. I have measured out my life with coffee spoons; I know the voices dying with a dying fall

      I chose this line because of the thought of measuring out your life seems like quite a sad thing. It makes me think that the narrator does not quite value his own life. It also makes me think that the narrator is currently over the hill, and thinks that death is coming.

    29. The yellow fog that rubs its back upon the window-panes, The yellow smoke that rubs its muzzle on the window-panes,

      I chose this line as I don't quite understand what is meant by yellow fog, it's quite confusing. It has provoked my thoughts as to what is meant by yellow fog.

    30. I am no prophet and here’s no great matter; I have seen the moment of my greatness flicker

      I took this as a self realization that he is only a mortal man, and he's nothing special. He does no see himself as special.

    31. In a minute there is time For decisions and revisions which a minute will reverse.

      This made me think that time is constant and no matter much we underestimate small fractions of time, they can have great everlasting impacts.

    32. Oh, do not ask, “What is it?” Let us go and make our visit.

      I really liked this line because it gave a spontaneous tone. Care free and long for experience. A split between adventurous and ignorance.

    33. And indeed there will be time To wonder, “Do I dare?” and, “Do I dare?”

      I wonder what he means by "Do I dare?" Does it have any meaning in the poem, or does mean something to the reader? It makes me wonder what he's daring for.

    34. In the room the women come and go Talking of Michelangelo.

      This line comes up twice. I wonder why Eliot keeps on referring to this. Why is Michelangelo important here? It makes me think that it supposed to give context to the situation.

    35. Oh, do not ask, “What is it?” Let us go and make our visit.

      This line makes me wonder about the situation that is happening, like what does he mean by, "What is it?" It just makes me feel weird inside.

    1. الهضم شكل 18.3.2\PageIndex{2}: يحدث كل من الهضم الميكانيكي والكيميائي في جميع أنحاء الجهاز الهضمي كما هو موضح في هذا الرسم البياني ، لكن الامتصاص يحدث فقط في المعدة والأمعاء الدقيقة والغليظة. هضم الطعام هو شكل من أشكال الهدم ، حيث يتم تقسيم الطعام إلى جزيئات صغيرة يمكن للجسم امتصاصها واستخدامها للطاقة والنمو والإصلاح. يحدث الهضم عندما ينتقل الطعام عبر الجهاز الهضمي. يبدأ في الفم وينتهي في الأمعاء الدقيقة. يتم امتصاص النواتج النهائية لعملية الهضم من الجهاز الهضمي ، وبشكل أساسي في الأمعاء الدقيقة. هناك نوعان مختلفان من الهضم يحدثان في الجهاز الهضمي: الهضم الميكانيكي والهضم الكيميائي. يلخص الرسم البياني التالي الأدوار التي تلعبها الأجهزة الهضمية المختلفة في الهضم الميكانيكي والكيميائي ، وكلاهما موصوف بالتفصيل أدناه. الهضم الميكانيكي الهضم الميكانيكي هو عملية فيزيائية يتم فيها تقسيم الطعام إلى قطع أصغر دون أن يتغير كيميائيًا. تبدأ مع قضمة الطعام الأولى وتستمر بينما تمضغ الطعام بأسنانك إلى قطع أصغر. تستمر عملية الهضم الميكانيكي في المعدة. هذا العضو العضلي يخض ويخلط الطعام الذي يحتوي عليه ، وهو عمل يقسم أي طعام صلب إلى قطع أصغر. على الرغم من أن بعض الهضم الميكانيكي يحدث أيضًا في الأمعاء ، إلا أنه يكتمل في الغالب بحلول الوقت الذي يغادر فيه الطعام المعدة. في تلك المرحلة ، يتم تغيير الطعام في الجهاز الهضمي إلى شبه سائل سميك يسمى الكيموس. الهضم الميكانيكي ضروري حتى يكون الهضم الكيميائي فعالاً. يزيد الهضم الميكانيكي بشكل كبير من مساحة سطح جزيئات الطعام بحيث يمكن العمل عليها بشكل أكثر فعالية عن طريق الإنزيمات الهاضمة. الهضم الكيميائي الهضم الكيميائي هو عملية كيميائية حيوية يتم فيها تحويل الجزيئات الكبيرة في الطعام إلى جزيئات أصغر يمكن امتصاصها في سوائل الجسم ونقلها إلى الخلايا في جميع أنحاء الجسم. تشمل المواد الموجودة في الطعام التي يجب هضمها كيميائيًا الكربوهيدرات والبروتينات والدهون والأحماض النووية. يجب تقسيم الكربوهيدرات إلى سكريات بسيطة ، وبروتينات إلى أحماض أمينية ، ودهون إلى أحماض دهنية وجلسرين ، وأحماض نووية إلى قواعد نيتروجين وسكريات. يحدث بعض الهضم الكيميائي في الفم والمعدة ، ولكن يحدث معظمه في الجزء الأول من الأمعاء الدقيقة (الاثني عشر). الانزيمات الهاضمة لا يمكن أن يحدث الهضم الكيميائي بدون مساعدة العديد من الإنزيمات الهضمية المختلفة. الإنزيمات عبارة عن بروتينات تحفز أو تسرع التفاعلات الكيميائية الحيوية. تفرز الإنزيمات الهاضمة عن طريق الغدد الخارجية أو الطبقة المخاطية للظهارة المبطنة للجهاز الهضمي. في الفم ، تفرز الغدد اللعابية إنزيمات الجهاز الهضمي. تفرز بطانة المعدة الإنزيمات كما تفعل بطانة الأمعاء الدقيقة. يتم إفراز العديد من إنزيمات الجهاز الهضمي بواسطة الخلايا الخارجية في البنكرياس ويتم نقلها عن طريق القنوات إلى الأمعاء الدقيقة. يسرد الجدول التالي العديد من الإنزيمات الهضمية الهامة ، والأعضاء و / أو الغدد التي تفرزها ، والمركبات التي تهضمها. يمكنك قراءة المزيد عنها أدناه. طاولة 18.3.1\PageIndex{1}: الانزيمات الهاضمة الانزيم الهضمي الجهاز والغدد التي تفرزها كومباوند إت هضم الأميليز الغدد اللعابية والبنكرياس أميلوز (عديد السكاريد) سكرايس الأمعاء الدقيقة السكروز (ديساكهاريد) اللاكتاز الأمعاء الدقيقة اللاكتوز (ديساكهاريد) ليباز الغدد اللعابية والبنكرياس دهون بيبسين المعدة بروتين التربسين البنكرياس بروتين كيموتربسين البنكرياس بروتين ديوكسيريبونوكلياز البنكرياس الحمض النووي ريبونوكلياز البنكرياس RNA نوكلياز الأمعاء الدقيقة أحماض نووية صغيرة الهضم الكيميائي للكربوهيدرات حوالي 80 في المائة من الكربوهيدرات القابلة للهضم في النظام الغذائي الغربي النموذجي تكون في شكل نبات السكاريد أميلوز ، والذي يتكون أساسًا من سلاسل طويلة من الجلوكوز وهو أحد مكونين رئيسيين من النشا. تشمل الكربوهيدرات الغذائية الإضافية الجليكوجين متعدد السكريات الحيواني ، جنبًا إلى جنب مع بعض السكريات ، والتي هي أساسًا ثنائي السكريات. لهضم الأميلوز والجليكوجين كيميائياً ، يلزم إنزيم الأميليز. يبدأ الهضم الكيميائي لهذه السكريات في الفم بمساعدة الأميليز في اللعاب. يحتوي اللعاب أيضًا على مادة مخاطية تعمل على تليين الطعام ، وكربونات الهيدروجين التي توفر الظروف القلوية المثالية لعمل الأميليز. يكتمل هضم الكربوهيدرات في الأمعاء الدقيقة ، بمساعدة الأميليز الذي يفرزه البنكرياس. في عملية الهضم ، يتم تقليل طول السكريات عن طريق كسر الروابط بين مونومرات الجلوكوز. يتم تقسيم الجزيئات الكبيرة إلى عديد السكاريد والسكريات الأقصر ، مما يؤدي إلى سلاسل أقصر من الجلوكوز تدريجيًا. والنتيجة النهائية هي جزيئات من السكريات البسيطة مثل الجلوكوز والمالتوز (التي تتكون من جزيئي جلوكوز) ، وكلاهما يمكن أن تمتصه الأمعاء الدقيقة. يتم هضم السكريات الأخرى بمساعدة إنزيمات مختلفة تنتجها الأمعاء الدقيقة. على سبيل المثال ، السكروز ، أو سكر المائدة ، هو ثنائي السكاريد الذي يتم تكسيره بواسطة إنزيم السكراز لتكوين الجلوكوز والفركتوز ، والتي يتم امتصاصها بسهولة عن طريق الأمعاء الدقيقة. يتطلب هضم سكر اللاكتوز الموجود في الحليب إنزيم اللاكتاز الذي يكسر اللاكتوز إلى جلوكوز وجلاكتوز ، ثم تمتصهما الأمعاء الدقيقة. أقل من نصف البالغين ينتجون كمية كافية من اللاكتاز ليتمكنوا من هضم اللاكتوز. أولئك الذين لا يستطيعون يقال إنهم يعانون من عدم تحمل اللاكتوز. الهضم الكيميائي للبروتينات تتكون البروتينات من عديد الببتيدات ، والتي يجب تقسيمها إلى الأحماض الأمينية المكونة لها قبل أن يتم امتصاصها. يحدث هضم البروتين في المعدة والأمعاء الدقيقة من خلال عمل ثلاثة إنزيمات أولية: البيبسين ، الذي تفرزه المعدة. والتربسين والكيموتريبسين يفرزهما البنكرياس. تفرز المعدة أيضًا حمض الهيدروكلوريك ، مما يجعل المحتويات شديدة الحموضة ، وهو أمر ضروري لعمل البيبسين. يتطلب التربسين والكيموتريبسين في الأمعاء الدقيقة بيئة قلوية للعمل. تعمل الصفراء من الكبد والبيكربونات من البنكرياس على تحييد الكيموس الحمضي لأنه يفرغ في الأمعاء الدقيقة. بعد أن يقوم البيبسين والتربسين والكيموتريبسين بتفكيك البروتينات إلى ببتيدات ، يتم تقسيمها إلى أحماض أمينية بواسطة إنزيمات أخرى تسمى الببتيدات ، والتي يفرزها البنكرياس أيضًا. الهضم الكيميائي للدهون يبدأ الهضم الكيميائي للدهون في الفم. تفرز الغدد اللعابية إنزيم الليباز الهضمي ، الذي يحطم الدهون قصيرة السلسلة إلى جزيئات تتكون من اثنين من الأحماض الدهنية. قد تحدث كمية ضئيلة من هضم الدهون في المعدة ، لكن معظم هضم الدهون يحدث في الأمعاء الدقيقة. يحدث هضم الدهون في الأمعاء الدقيقة بمساعدة إنزيم ليباز آخر من البنكرياس وكذلك الصفراء التي يفرزها الكبد. الصفراء مطلوبة لهضم الدهون لأن الدهون دهنية ولا تذوب في الكيموس المائي. تستحلب الصفراء ، أو تكسر ، الكريات الكبيرة من الدهون الغذائية إلى كريات أصغر بكثير ، تسمى المذيلات ، مثل منظف الأطباق الذي يكسر الشحوم. توفر المذيلات مساحة سطح أكبر بكثير ليتم العمل عليها بواسطة الليباز وأيضًا توجيه الرؤوس المحبة للماء ("المحبة للماء") للأحماض الدهنية إلى الخارج في الكيموس المائي. يمكن للليباز بعد ذلك الوصول إلى المذيلات وتقسيمها إلى جزيئات الأحماض الدهنية الفردية. الهضم الكيميائي للأحماض النووية يتم هضم الأحماض النووية (DNA و RNA) في الأطعمة في الأمعاء الدقيقة بمساعدة كل من إنزيمات البنكرياس والإنزيمات التي تنتجها الأمعاء الدقيقة نفسها. تقوم إنزيمات البنكرياس المسماة ribonuclease و deoxyribonuclease بتفكيك RNA و DNA ، على التوالي ، إلى أحماض نووية أصغر. يتم تقسيم هذه بدورها إلى قواعد النيتروجين والسكريات بواسطة إنزيمات الأمعاء الدقيقة التي تسمى نوكلياز. الهضم الكيميائي بواسطة Gut Flora عادة ما يسكن الجهاز الهضمي البشري تريليونات من البكتيريا ، والتي يساهم بعضها في الهضم. فيما يلي مثالان فقط من بين عشرات الأمثلة: الكربوهيدرات الأكثر شيوعًا في النباتات ، وهي السليلوز ، لا يمكن هضمها بواسطة الجهاز الهضمي البشري. ومع ذلك ، يتم هضم كميات صغيرة من السليلوز بواسطة البكتيريا في الأمعاء الغليظة. تساعد بكتيريا معينة في الأمعاء الدقيقة على هضم اللاكتوز ، والذي لا يستطيع الكثير من البالغين هضمه. كنتيجة ثانوية لهذه العملية ، تنتج البكتيريا حمض اللاكتيك الذي يزيد من إفراز الإنزيمات الهاضمة وامتصاص المعادن مثل الكالسيوم والحديد. استيعاب عندما ينتهي الهضم ، ينتج عنه العديد من جزيئات المغذيات البسيطة التي يجب أن تمر خلال عملية الامتصاصمن الجهاز الهضمي عن طريق الدم أو الليمفاوية حتى يمكن للخلايا أن تستخدمها في جميع أنحاء الجسم. يتم امتصاص بعض المواد في المعدة والأمعاء الغليظة. على سبيل المثال ، يتم امتصاص الماء في كلا الجهازين ، كما يتم امتصاص بعض المعادن والفيتامينات في الأمعاء الغليظة. ومع ذلك ، يتم امتصاص حوالي 95 في المائة من جزيئات المغذيات في الأمعاء الدقيقة. يحدث امتصاص غالبية هذه الجزيئات في الجزء الثاني من الأمعاء الدقيقة ، المسمى الصائم. ومع ذلك، هناك بعض الاستثناءات القليلة. على سبيل المثال ، يُمتص الحديد في الاثني عشر ، وفيتامين ب 12 يُمتص في الجزء الأخير من الأمعاء الدقيقة المسمى الدقاق. بعد امتصاصها في الأمعاء الدقيقة ، يتم نقل جزيئات المغذيات إلى أجزاء أخرى من الجسم للتخزين أو المزيد من التعديل الكيميائي. على سبيل المثال، النسيج الظهاري المبطن للأمعاء الدقيقة متخصص في الامتصاص. يحتوي على العديد من التجاعيد ومغطاة بالزغب والزغابات الدقيقة ، مما يخلق مساحة سطحية هائلة للامتصاص. كما هو موضح في الرسم البياني أدناه ، تحتوي كل خلية أيضًا على شبكة من الشعيرات الدموية والأوعية الليمفاوية الدقيقة تسمى اللاكتيل بالقرب من سطحها. تنقل الطبقة السطحية الرقيقة للخلايا الظهارية للزغابات المغذيات من تجويف الأمعاء الدقيقة إلى هذه الشعيرات الدموية واللاكتيلات. يمتص الدم في الشعيرات الدموية معظم الجزيئات ، بما في ذلك السكريات البسيطة والأحماض الأمينية والجليسرول والأملاح والفيتامينات القابلة للذوبان في الماء (فيتامين سي والعديد من فيتامينات ب). يمتص الليمف الموجود في اللاكتيل الأحماض الدهنية والفيتامينات التي تذوب في الدهون (الفيتامينات أ ، د ، هـ ، ك). شكل 18.3.3\PageIndex{3}: هذا الرسم المبسط للغاية للزغابات المعوية (الزغابات الجماعية) يُظهر الشعيرات الدموية واللاكتيلات الموجودة بداخلها والتي تحمل المواد الممتصة. لاحظ أن كل خلية في الطبقة السطحية الرقيقة من الزغابات مغطاة فعليًا بالميكروفيلي التي تزيد من مساحة السطح للامتصاص. الميزة: جسدي البشري لا تسير عملية الهضم دائمًا كما ينبغي. يعاني الكثير من الأشخاص من عسر الهضم ، أو عسر الهضم ، وهي حالة من ضعف الهضم. قد تشمل الأعراض الامتلاء أو الألم في الجزء العلوي من البطن ، أو حرقة المعدة ، أو الغثيان ، أو التجشؤ ، أو مزيج من هذه الأعراض. تحدث غالبية حالات عسر الهضم دون وجود دليل على وجود مرض عضوي من المحتمل أن يفسر الأعراض. قد يكون القلق أو بعض الأطعمة أو الأدوية (مثل الأسبرين) من العوامل المساهمة في هذه الحالات. في حالات أخرى ، يكون عسر الهضم أحد أعراض مرض عضوي ، وغالبًا ما يكون مرض الجزر المعدي المريئي (GERD) أو التهاب المعدة. في عدد قليل من الحالات ، يكون عسر الهضم أحد أعراض القرحة الهضمية في المعدة أو الاثني عشر ، وعادة ما تسببها عدوى بكتيرية. نادرًا ما يكون عسر الهضم علامة على الإصابة بالسرطان. عادة لا تقلق نوبة عسر الهضم العرضية ، خاصة عند الأشخاص الذين تقل أعمارهم عن 55 عامًا. ومع ذلك ، إذا كنت تعاني من عسر هضم متكرر أو مزمن ، فمن الجيد أن ترى الطبيب. إذا تسبب اضطراب كامن مثل ارتجاع المريء أو القرحة في عسر الهضم ، فيمكن ويجب علاج ذلك. إذا لم يتم اكتشاف مرض عضوي ، يمكن للطبيب أن يوصي بتغييرات في نمط الحياة أو علاجات للمساعدة في منع أو تهدئة أعراض عسر الهضم الحاد. قد تتضمن التغييرات في نمط الحياة تعديلات في عادات الأكل ، مثل الأكل ببطء أكثر أو تناول وجبات أصغر أو تجنب الأطعمة الدهنية. قد يُنصح أيضًا بالامتناع عن تناول بعض الأدوية ، خاصةً على معدة فارغة. قد يوصى أيضًا باستخدام مضادات الحموضة أو الأدوية الأخرى لتخفيف الأعراض. ملخص الهضم هو شكل من أشكال الهدم ، حيث يتم تقسيم الطعام إلى جزيئات صغيرة يمكن للجسم امتصاصها واستخدامها للطاقة والنمو والإصلاح. يحدث الهضم عندما يتحرك الطعام عبر الجهاز الهضمي (GI). يتم التحكم في عملية الهضم عن طريق الهرمونات والأعصاب. الهضم الميكانيكي هو عملية فيزيائية يتم فيها تقسيم الطعام إلى قطع أصغر دون أن يتغير كيميائيًا. يحدث بشكل رئيسي في الفم والمعدة. الهضم الكيميائي هو عملية كيميائية يتم فيها تحويل الجزيئات الكبيرة بما في ذلك الكربوهيدرات والبروتينات والدهون والأحماض النووية في الطعام إلى جزيئات مغذية بسيطة يمكن امتصاصها في سوائل الجسم. يتم هضم الكربوهيدرات كيميائيًا إلى السكريات ، والبروتينات إلى الأحماض الأمينية ، والدهون إلى الأحماض الدهنية ، والأحماض النووية للنيوكليوتيدات الفردية. يتطلب الهضم الكيميائي إنزيمات هضمية. تقوم فلورا الأمعاء بعملية هضم كيميائية إضافية. يحدث الامتصاص عندما يتم امتصاص جزيئات المغذيات البسيطة الناتجة عن الهضم في الدم أو اللمف.

      كيف يمكنني نسخ المحتوى

    2. repolarization - this happens when potassium ion channel opens up and the action potential ends. This is called the repolarization.

    3. Resting potential is the difference in electrical charge across the plasma membrane of a neuron that is not actively transmitting a nerve impulse

    4. Sodium-potassium pump is the active transport mechanism in which sodium ions are pumped out of a cell and potassium ions are pumped into the cell with the help of a carrier protein and energy from ATP

    5. Thus, ATP is the higher energy form (the recharged battery) while ADP is the lower energy form (the used battery). Think of it as the “energy currency” of the cell. If a cell needs to spend energy to accomplish a task, the ATP molecule splits off one of its three phosphates, becoming ADP (Adenosine di-phosphate) + phosphate.

    6. difference in electrical charge

      potential difference

    7. nerve impulse - electrical signal transmitted by the nervous system

    1. Those who are more likely to bully: Bullies are often thought of as having low self-esteem, and then bully others to feel better about themselves. Although this can occur, many bullies in fact have high levels of self-esteem. They possess considerable popularity and social power and have well-connected peer relationships. They do not lack self-esteem, and instead lack empathy for others. They like to dominate or be in charge of others.

      Trumpsters

    1. For the hydrogen atom, the peak in the radial probability plot occurs at r = 0.529 Å (52.9 pm), which is exactly the radius calculated by Bohr for the n = 1 orbit.

      n = bohr probabilities for electrons in n orbits around the nucleus

      For the hydrogen atom, the peak in the radial probability plot occurs at r = 0.529 Å (52.9 pm), which is exactly the radius calculated by Bohr for the n = 1 orbit.

    2. he

      The

    1. redox reaction

      Typo on graphic that was confusing, overall reaction shows incorrect reduction reactants.

      Overall cell reaction: Y + Z\(^+\) → Y\(^+\) + Z

    1. monosaccharide, aldose, ketose, tri, tet, pent, hex, suffix -ose, carbonyl groups, aldehyde, ketone,

      chiral carbon, central carbon, carbon atom with four groups attached to it, likely stereoisomers,

      stereoisomer, enantiomers,

      glyceraldehyde, enantiomers, D and L basis for all other monosaccharides with > 3 carbons,

      optically active substances, dextrorotary +, rotates to left (counterclockwise) levorotary -, rotates to right (clockwise)

    1. the following video this problem is solved, and it was noted that the COCl2 must be a reactant

      So we basically just combine the chemicals?

    2. polynomial equations

      Will this involve algebra?

    1. stoichiometric

      Will we be using stoichiometry?

    2. RICE diagram

      Will this work for every reaction?

    3. Since this reaction can go in the forward or reverse direction,

      Can all reactions do this or only a specific few?

  3. Feb 2021
    1. orbital diagram spin up, spin down,

      • 1/2, - 1/2, every orbital has two electrons, up arrow, down arrow, lowest energy orbitals, ground state, atomic number = z
    1. B. How DNA in eukaryotic cells looks once it is replicated and the cell is about to divide

      Can anyone see this?

    1. Polarity is a physical property of compounds which relates other physical properties such as melting and boiling points, solubility, and intermolecular interactions between molecules.

      What is polarity?

    1. When water moves into a cell by osmosis, osmotic pressure may build up inside the cell. If a cell has a cell wall, the wall helps maintain the cell’s water balance. Osmotic pressure is the main cause of support in many plants.

      Osmotic pressure