Carbohydrates and Glycolysis Metabolism Chapter 8 Quiz
18 Questions
6 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

Which enzyme breaks down lactose in the intestinal mucosa?

  • Amylase
  • Lactase (correct)
  • Maltase
  • Sucrase

What are the final monosaccharides formed after the breakdown of sucrose?

  • Galactose and fructose
  • Fructose only
  • Glucose and galactose
  • Glucose and fructose (correct)

Where does glycolysis primarily occur in the cell?

  • Mitochondria
  • Lysosome
  • Cytosol (correct)
  • Endoplasmic reticulum

Which molecule is generated from glycolysis that carries hydrogen to the respiratory chain?

<p>NADH + H (C)</p> Signup and view all the answers

In anaerobic glycolysis, what is the final product when pyruvate is converted?

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

Which tissues are involved in the formation of lactic acid as a result of carbohydrate metabolism?

<p>Skeletal muscle and brain (A)</p> Signup and view all the answers

Which stage of obtaining energy from food involves the conversion of large molecules like proteins into small compounds like amino acids and glucose?

<p>Stage 1 (C)</p> Signup and view all the answers

In most cell types, is the rate of glucose transport across the cell membrane a limiting factor for glucose metabolism?

<p>No, it is not a limiting factor (C)</p> Signup and view all the answers

Which tissue reflects blood glucose concentration and does not face limitations in glucose transport even at low blood sugar levels?

<p>Erythrocytes (A)</p> Signup and view all the answers

Which type of transporter regulates the transport of glucose into a myocyte and is influenced by insulin?

<p>GLUT4 (B)</p> Signup and view all the answers

At what stage does the breakdown of carbohydrates typically begin?

<p>In the mouth (A)</p> Signup and view all the answers

Which stage involves the conversion of acetyl group of acetyl CoA to carbon dioxide and water through TCA cycle and respiratory chain?

<p>Stage 3 (D)</p> Signup and view all the answers

What role does a-amylase play in breaking down polysaccharides?

<p>Breaking down a-1,4 glycoside bonds by skipping a bond (D)</p> Signup and view all the answers

Which enzyme secreted from the pancreas is very active in breaking down polysaccharides?

<p>a-amylase (C)</p> Signup and view all the answers

What happens when the activity of a-amylase stops?

<p>2 glucose units remain at the end of the chain or the branch point (C)</p> Signup and view all the answers

Which enzyme plays a role in breaking down the a1 ® 4 bond in carbohydrates?

<p>a-glucosidase (B)</p> Signup and view all the answers

What is the function of a-dextrinase in carbohydrate digestion?

<p>Breaking down a-1,6 glycoside bonds (B)</p> Signup and view all the answers

Where are other hydrolytic enzymes secreted for the completion of carbohydrate digestion?

<p>Brushy edge of the small intestine mucosa (A)</p> Signup and view all the answers

Flashcards

Stage 1 of Energy Production

Breaking down large food molecules (proteins and carbs) into smaller units (amino acids and glucose).

Stage 2 of Energy Production

Converting small molecules into a central molecule called acetyl CoA.

Stage 3 of Energy Production

Using the acetyl group from acetyl CoA to create CO2, water and a large amount of energy through the TCA cycle and electron transport.

Glucose Transport Rate

The speed at which glucose moves across cell membranes.

Signup and view all the flashcards

Intracellular Glucose

Glucose concentration inside cells.

Signup and view all the flashcards

Rate-limiting step (Glucose)

A step in a metabolic process that controls the overall process speed.

Signup and view all the flashcards

GLUT4

A type of glucose transporter that moves glucose into muscle cells and is regulated by insulin.

Signup and view all the flashcards

Glycolysis

The metabolic pathway that breaks down glucose to produce energy.

Signup and view all the flashcards

Aerobic Glycolysis

Glycolysis occurring when oxygen is available.

Signup and view all the flashcards

Anaerobic Glycolysis

Glycolysis occurring without oxygen.

Signup and view all the flashcards

Lactic Acid

A byproduct of anaerobic glycolysis in certain tissues.

Signup and view all the flashcards

Blood Lactate Level

The concentration of lactate in the blood, influenced by production and removal rates.

Signup and view all the flashcards

Carbohydrate Digestion

Carbohydrate breakdown starts in the mouth and continues in the intestines aided by enzymes.

Signup and view all the flashcards

Monosaccharides

Simple sugars formed from carbohydrate breakdown.

Signup and view all the flashcards

Glucose Metabolism

The process of converting glucose into energy and other molecules.

Signup and view all the flashcards

Cellular Metabolism

The sum of chemical reactions that take place in a cell including glycolysis etc.

Signup and view all the flashcards

Location of Glycolysis Enzymes

All glycolysis enzymes are in the cell's cytoplasm.

Signup and view all the flashcards

Glycolysis Precursors

Glycolysis produces molecules used in other metabolic processes.

Signup and view all the flashcards

Study Notes

Stages of Obtaining Energy from Food

  • There are three stages of obtaining energy from food:
    • Stage 1: Converting large molecules (proteins and polysaccharides) into small compounds (amino acids and glucose)
    • Stage 2: Converting small molecules into central simple compounds (mainly acetyl CoA)
    • Stage 3: Converting acetyl group of acetyl CoA to carbon dioxide and water through TCA cycle and respiratory chain

Cellular Metabolism

  • The rate of glucose transport across the cell membrane is not rate-limiting for glucose metabolism
  • In most cell types, intracellular glucose concentration reflects blood glucose levels
  • Erythrocyte is an example of a tissue in which glucose transport is not rate-limiting

Glucose Transport

  • The glucose transport proteins (GLUT) have 12 transmembrane domains, but their properties differ from one tissue to another
  • GLUT4 transports glucose into myocytes and is regulated by insulin

Digestion and Absorption of Carbohydrates

  • Carbohydrate breakdown begins in the mouth
  • Enzymes such as α-galactosidase and lactase break down lactose and sucrase breaks down sucrose in the intestinal mucosa
  • Monosaccharides (glucose, galactose, and fructose) are formed from the breakdown of carbohydrates

Glycolysis

  • Glycolysis is the principal metabolism route for glucose
  • All enzymes involved in glycolysis are in the cytosol
  • Glycolysis generates precursors for biosynthetic pathways in addition to providing ATP
  • Glycolysis can be summarized as: C6H12O6 + 6H2O → 6CO2 + 6H2O + energy (heat-ATP-NADH)

Anaerobic and Aerobic Glycolysis

  • In aerobic glycolysis, pyruvate enters the TCA cycle and is broken down to CO2 and H2O
  • In anaerobic glycolysis, pyruvate is converted to lactate
  • Anaerobic glycolysis occurs in cells without mitochondria

Lactate and Pyruvate

  • Lactic acid is formed as a result of carbohydrate metabolism in tissues such as skeletal muscle, brain, RBC, renal medulla, and skin
  • Blood lactate level depends on formation in these tissues and metabolism rates in the liver and kidney

Studying That Suits You

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

Quiz Team

Description

Test your knowledge on the Introduction to Metabolism and Glycolysis as outlined in the book by Assist.Prof. Hadi Karimkhani. The quiz covers topics such as the stages of obtaining energy from food, the conversion of molecules, and the role of acetyl CoA in energy production.

More Like This

Carbohydrate Biochemistry Quiz
12 questions
Carbohydrate Biochemistry Fundamentals
10 questions
Use Quizgecko on...
Browser
Browser