Glikolīze: Procesi un posmi
15 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Kāda ir fosforilgrupas loma enerģijas metabolismā?

  • Tā stimulē glikozes ražošanu.
  • Tā inhibē ATP sintēzi.
  • Tā nodrošina makroergiskos savienojumus. (correct)
  • Tā samazina NADPH ražošanu.

    • Kurei vielai ir loma oxidatīvā fosforilēšanā?

  • NADH (correct)
  • ATP
  • ADP
  • NADP+

    • Kas notiek ar ATP līmeni, kad tiek palielināta glikozes koncentrācija?

  • ATP tiek uzkrāts muskuļos.
  • ATP līmenis samazinās.
  • ATP līmenis palielinās. (correct)
  • ATP līmenis paliek nemainīgs.

    • Kāda ir NADPH loma bioloģiskajās reakcijās?

    <p>Tas piedalās redoks reakcijās. (B)</p> Signup and view all the answers

    Kāds ir piruvāta loma anaerobās elpošanas procesā?

    <p>Tas tiek pārveidots par pienskābi. (D)</p> Signup and view all the answers

    Kāds ir vissvarīgākais līdzeklis insulīna ietekmē glikozes metabolismā?

    <p>Tā stimulē glikozes uzkrāšanos aknās. (D)</p> Signup and view all the answers

    Kādā veidā ATP ietekmē citrāta sintēzi?

    <p>ATP inhibē citrāta sintēzi. (C)</p> Signup and view all the answers

    Kura no šīm vielām ir fermentu inhibitori glikozes metabolismā?

    <p>Citrāta. (D)</p> Signup and view all the answers

    Kurus reaktānus izmanto glikozes sintēzē no piruvāta?

    <p>Fosfātu un NADPH. (C)</p> Signup and view all the answers

    Kāda ir loma glikoneoģenēzē?

    <p>Sintezēt glikozi no neogļhidrātiem avotiem. (C)</p> Signup and view all the answers

    Kāda ir anaerobās glikolīzes galvenā produkta?

    <p>Pienskābe. (C)</p> Signup and view all the answers

    Kādām vielām ir loma ribozu sintēzē?

    <p>ATP un NADPH. (B)</p> Signup and view all the answers

    Kas ir glikozes degradujošs process, kas veicina olbaltumvielu ražošanu?

    <p>Fermentācija. (D)</p> Signup and view all the answers

    Kura viela piedalās kā koenzīms Krebs ciklā?

    <p>CoA. (D)</p> Signup and view all the answers

    Signup and view all the answers

    Study Notes

    Glycolysis Summary

    • Glycolysis is the anaerobic oxidation of glucose, occurring in all tissues when oxygen is limited (anaerobic conditions).
    • It is the sole energy source for cells without mitochondria.
    • The process takes place in the cytoplasm.

    Aerobic Conditions

    • The reaction involves 10 steps.
    • Results in 2 pyruvate molecules, 4 ATP molecules, and 2 NADH molecules (if sufficient oxygen for the Krebs cycle).

    Anaerobic Conditions

    • The reaction involves 11 steps.
    • Results in 2 lactate (lactic acid) molecules and 2 ATP molecules (when oxygen is limited).
    • If oxygen supply is restored, lactate is oxidized into pyruvate and enters the Krebs cycle.

    Glycolysis Steps (Phase 1 - Preparatory Phase)

    • Steps 1 through 5 utilize 2 ATP, and produce 2 identical triose phosphate molecules.

    Glycolysis Steps (Phase 2 - Energy Payoff Phase)

    • Steps 6 through 10 produce 4 ATP and 2 NADH from 2 triose phosphates, resulting in 2 pyruvate molecules.

    Fermentation (Anaerobic)

    • Yeast and some microorganisms can convert glucose to ethanol and CO2.
    • Humans and other higher organisms do not use fermentation to process glucose.

    Phosphorylation - Step 1

    • Hexokinase (or glucokinase) phosphorylates glucose using ATP, creating glucose-6-phosphate (glucose-6-P).
    • This reaction is irreversible.

    Isomerization - Step 2

    • Phosphoglucoisomerase converts glucose-6-P to fructose-6-P.

    Second Phosphorylation - Step 3

    • Phosphofructokinase-1 phosphorylates fructose-6-P to fructose-1,6-bisphosphate, consuming another ATP.
    • This reaction is irreversible and a major regulatory step in glycolysis.

    Cleavage - Step 4

    • Aldolase cleaves fructose-1,6-bisphosphate into two 3-carbon molecules: glyceraldehyde-3-phosphate (GAP) and dihydroxyacetone phosphate (DHAP).

    Isomerization - Step 5

    • Triose phosphate isomerase converts DHAP into GAP.
    • Now, there are two molecules of glyceraldehyde-3-phosphate, which can proceed to phase two of glycolysis.

    Oxidation - Step 6

    • Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) oxidizes glyceraldehyde-3-phosphate; NAD+ is reduced to NADH and a high-energy intermediate is formed (1,3-bisphosphoglycerate).

    Dephosphorylation - Step 7

    • Phosphoglycerate kinase transfers a phosphate group from 1,3-bisphosphoglycerate to ADP, forming ATP.
    • This is substrate-level phosphorylation.

    Transfer - Step 8

    • Phosphoglycerate mutase converts 3-phosphoglycerate into 2-phosphoglycerate.

    Dehydration - Step 9

    • Enolase removes water from 2-phosphoglycerate, forming phosphoenolpyruvate (PEP).

    Dephosphorylation - Step 10

    • Pyruvate kinase transfers a phosphate group from PEP to ADP, forming a second ATP.
    • This is another substrate-level phosphorylation reaction, and the final step of glycolysis.

    Lactate Formation (Anaerobic)

    • In the absence of oxygen, pyruvate is reduced to lactate by lactate dehydrogenase, regenerating NAD+.
    • This allows glycolysis to continue.

    Glycolysis Summary (Aerobic)

    • Net yield of energy per glucose molecule: 2 ATP, 2 NADH
    • Location: Cytoplasm

    Glycolysis Summary (Anaerobic)

    • Net yield of energy per glucose molecule: 2 ATP
    • Location: Cytoplasm

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Biochem 2.kolokvijs PDF

    Description

    Glikolīze ir glikozes anaerobā oksidācija, kas notiek visās šūnās skābekļa ierobežojuma gadījumā. Šajā testa jautājumu komplektā tiks aplūkoti visu 10 glikolīzes posmu soli pa solim un to rezultāti gan aerobos, gan anaerobos apstākļos.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser