CORE Biology (Short Course) - 9221 OxfordAQA

Control Of Blood Glucose

Aperçu

Drink a glass of sweetened orange juice and, for a few minutes, a large quantity of sugar pours out of your small intestine and into your bloodstream. Two hours later a blood test would struggle to prove you had drunk anything at all. Something worked very hard, very quietly, to put that number back where it started, and it did so without you noticing or deciding anything.

This lesson is about that something: a small organ tucked behind the stomach that tastes the blood flowing past it and answers with one of two hormones. You will learn what insulin does, what glucagon does, why the body needs both rather than one, and where the glucose actually goes when it leaves the blood. You will then look at what happens when that system stops working properly, in the two forms of diabetes named on the specification, and you will practise reading the blood glucose graphs that a question on this topic is most likely to put in front of you.

Objectifs

  1. The blood glucose concentration is monitored and controlled by the pancreas. Much of the glucose is stored as glycogen in the liver and muscles. When these stores are full, excess glucose is stored as lipid.
  2. If blood glucose levels are too high, the pancreas produces the hormone insulin, which allows the glucose to move from the blood into the cells.
  3. When blood glucose levels fall, the pancreas produces a second hormone, glucagon. This causes glycogen to be converted into glucose and released into the blood.
  4. In Type 1 diabetes a person’s blood glucose level may be too high because the pancreas does not produce enough insulin. Type 1 diabetes may be controlled by careful diet, exercise, and by injecting insulin.
  5. Type 2 diabetes develops when the body does not respond to its own insulin. Obesity is a significant factor in the development of Type 2 diabetes. Type 2 diabetes can be controlled by careful diet, exercise and by drugs that help the cells to respond to insulin.

Carte mentale

Ce theme est schematise pour montrer comment les idees se relient.

Ouvrez la carte mentale dans l'application

Note de cours

Glucose in the blood of a healthy person sits inside a narrow band. Before a meal the concentration is typically around 4 to 6 mmol per dm3, and even after a heavy plate of rice it rarely passes about 8 mmol per dm3 and is back near the starting figure within roughly two hours. That stability is strange when you think about what it is up against: meals arrive at unpredictable times and in unpredictable sizes, while your brain and muscles withdraw glucose from the blood every second of the day and night, including the eight hours you spend asleep and eating nothing. Supply is lumpy and demand is continuous, yet the concentration barely shifts.

Fiche complete disponible sur l'application Green Bridge

Installez l'application Green Bridge CBT sur votre telephone ou votre ordinateur pour acceder a toute la bibliotheque IGCSE : sujets d'examen, baremes, cartes mentales, fiches memo et lecons audio.

Notes de cours complètes avec diagrammes
Assistant d'apprentissage piloté par l'IA
Des examens blancs chronometres, corriges des que vous terminez
Disponible sur Android, Windows, macOS et Linux Application iOS bientot disponible

Évaluation de la leçon

Félicitations, vous avez terminé la leçon sur Control Of Blood Glucose. Maintenant que vous avez exploré le concepts et idées clés, il est temps de mettre vos connaissances à lépreuve. Cette section propose une variété de pratiques des questions conçues pour renforcer votre compréhension et vous aider à évaluer votre compréhension de la matière.

Vous rencontrerez un mélange de types de questions, y compris des questions à choix multiple, des questions à réponse courte et des questions de rédaction. Chaque question est soigneusement conçue pour évaluer différents aspects de vos connaissances et de vos compétences en pensée critique.

Utilisez cette section d'évaluation comme une occasion de renforcer votre compréhension du sujet et d'identifier les domaines où vous pourriez avoir besoin d'étudier davantage. Ne soyez pas découragé par les défis que vous rencontrez ; considérez-les plutôt comme des opportunités de croissance et d'amélioration.

  1. Which organ monitors the concentration of glucose in the blood? A. The liver B. The pancreas C. The kidney D. The small intestine Answer: B
  2. Blood glucose concentration has fallen below normal. Which hormone is released, and what does it cause? A. Insulin, causing glucose to be stored as glycogen B. Insulin, causing glycogen to be converted into glucose C. Glucagon, causing glucose to be stored as glycogen D. Glucagon, causing glycogen to be converted into glucose Answer: D
  3. Where is excess glucose stored once the glycogen stores in the liver and muscles are full? A. As lipid B. As protein C. As extra glycogen in the pancreas D. As starch Answer: A
  4. Which statement describes Type 2 diabetes? A. The pancreas produces too much insulin B. The body does not respond to its own insulin C. The liver cannot store glycogen D. The pancreas produces no glucagon Answer: B
  5. A man's blood glucose concentration rises from 5.0 to 8.0 mmol per dm3 after a meal. What is the percentage increase? A. 37.5% B. 50% C. 60% D. 160% Answer: C

Travaillez ces questions dans l'application

Travaillez ces questions dans l'application

Pratiquez des questions blanches

Vous voulez vous entraîner sur des questions blanches sur Control Of Blood Glucose ? Téléchargez lapplication Green Bridge CBT pour accéder à des questions blanches et à des évaluations complètes sur ce sujet.

Téléchargez l'application sur Google Play.

Tout ce dont vous avez besoin pour exceller au JAMB, WAEC et NECO.

Green Bridge CBT Mobile App
Assistant de chat d'apprentissage personnalisé par IA
Plus de 200 000 questions d'examen IGCSE, JAMB, WAEC et NECO.
Plus de 1200 notes de cours
Assistance Hors Ligne - Apprenez à Tout Moment, Partout
Horaire du Pont Vert
Résumés littéraires et questions potentielles
Suivez vos performances et votre progression
Explications Approfondies pour un Apprentissage Complet