Biochemistry Chapter on Energy Sources

Questions and Answers

What is the primary source of energy used by cells in glycolysis?

Amino acids

Glycerol

Glucose (correct)

Fatty acids

Which component of red blood cells is involved in transporting bicarbonate ions?

Cl−/HCO3− antiporter (correct)

ATP synthase

Calcium channel

Na+/K+ pump

What does erythrocytosis indicate?

Reduced oxygen-carrying capacity

Increased hematocrit (correct)

Abnormal red blood cell shapes

Decreased hemoglobin levels

What percentage of glucose is used in the HMP shunt?

10% Signup and view all the answers

What term describes the presence of red blood cells of varying sizes?

Anisocytosis Signup and view all the answers

What role does the bicarbonate ion play in red blood cells?

It helps in pH regulation and CO2 transport. Signup and view all the answers

What is the primary function of the Cl−/HCO3− antiporter in red blood cells?

To export HCO3− and transport CO2 Signup and view all the answers

What is the correct interpretation of increased hematocrit in a blood test?

Indicates erythrocytosis Signup and view all the answers

What activates macrophages?

IFN-γ Signup and view all the answers

What happens when Lipid A binds to the CD14 receptor on macrophages?

It activates macrophages to release pro-inflammatory cytokines. Signup and view all the answers

Which characteristic describes macrophages in granulomas?

They can fuse to form giant cells. Signup and view all the answers

What is the potential consequence of an overactive immune response due to Lipid A?

Widespread inflammation and septic shock. Signup and view all the answers

Which type of macrophage is primarily found in the liver?

Kupffer cells Signup and view all the answers

In what way can macrophages function relative to MHC II?

They can function as antigen-presenting cells via MHC II. Signup and view all the answers

Which of the following describes septic shock?

Involves a drastic drop in blood pressure and multiple organ failure. Signup and view all the answers

What role do pro-inflammatory cytokines play in the immune response?

They activate macrophages and promote inflammation. Signup and view all the answers

What is a key role of macrophages in the context of sepsis?

They interact with Lipopolysaccharide (LPS) from Gram-negative bacteria. Signup and view all the answers

Which type of macrophage is located in connective tissue?

Histiocytes Signup and view all the answers

Why is the response triggered by Lipid A necessary in fighting infections?

It stimulates the release of immune mediators. Signup and view all the answers

Which feature correctly identifies activated macrophages?

They can perform antibody-dependent cellular cytotoxicity. Signup and view all the answers

What can excessive release of pro-inflammatory cytokines result in?

A dysfunctional immune response leading to septic shock. Signup and view all the answers

Which outcome is linked to severe inflammation caused by an active immune response?

Possibility of multiple organ failure. Signup and view all the answers

What is the role of osteoclasts?

They are involved in bone resorption. Signup and view all the answers

Which statement about microglial cells is correct?

They are the resident macrophages in the brain. Signup and view all the answers

What can be an underlying effect of a balanced immune response?

Melioration of overall health and reduced infections. Signup and view all the answers

What is the main benefit of macrophages releasing pro-inflammatory cytokines upon activation?

To draw additional immune cells to the site of infection. Signup and view all the answers

What characterizes the interaction between macrophages and Lipid A?

Lipid A induces inflammation by binding to macrophages. Signup and view all the answers

How does an overactive immune response compromise health?

It can cause systemic inflammation leading to shock. Signup and view all the answers

What is the primary role of dendritic cells in the immune system?

To act as a link between innate and adaptive immune systems. Signup and view all the answers

What type of infections do eosinophils primarily defend against?

Helminthic infections Signup and view all the answers

Which of the following characteristics is NOT associated with dendritic cells?

Directly producing cytotoxic T-cells. Signup and view all the answers

How do dendritic cells present exogenous antigens?

On both MHC class I and MHC class II molecules. Signup and view all the answers

Which characteristic distinguishes neutrophils from eosinophils?

Multilobed nucleus Signup and view all the answers

What is the primary function of basophils in the immune response?

Mediation of allergic reactions Signup and view all the answers

In addition to antigen presentation, what other capability do dendritic cells have?

They can stimulate T-cells. Signup and view all the answers

What receptors do dendritic cells express on their surface?

MHC class I and II as well as Fc receptors. Signup and view all the answers

Which type of granules are densely packed in basophils?

Basophilic granules Signup and view all the answers

What is a notable characteristic of the granules found in eosinophils?

Uniform size and eosinophilic Signup and view all the answers

Which enzyme is NOT found in neutrophils?

Major basic protein Signup and view all the answers

Which role does lactoferrin play in neutrophils?

Facilitates iron sequestration Signup and view all the answers

What substance do basophils release to promote vasodilation?

Histamine Signup and view all the answers

Which type of leukocyte is primarily involved in phagocytosis?

Neutrophils Signup and view all the answers

What is the primary role of eosinophils in relation to antigen-antibody complexes?

To phagocytize the complexes Signup and view all the answers

What does poikilocytosis refer to in blood smears?

Varying shapes of red blood cells Signup and view all the answers

What indicates reticulocyte immaturity in blood?

Presence of residual ribosomal RNA Signup and view all the answers

What is demonstrated by the bluish color (polychromasia) of reticulocytes on a Wright-Giemsa stain?

Residual ribosomal RNA Signup and view all the answers

What process do monocytes undergo when they enter tissues?

Differentiate into macrophages Signup and view all the answers

What is the primary characteristic of reticulocytes?

Immaturity and presence in bloodstream Signup and view all the answers

What can an increase in reticulocytes indicate?

Active erythroid proliferation Signup and view all the answers

Which feature correctly identifies reticulocytes compared to mature red blood cells?

Presence of ribosomal RNA Signup and view all the answers

What is suggested by the presence of polychromasia in a blood smear?

Hemolytic anemia Signup and view all the answers

What is the main function of the Golgi apparatus in plasma cells?

Processing and packaging of antibodies Signup and view all the answers

Where are plasma cells predominantly found in the body?

Bone marrow Signup and view all the answers

What feature is often used to illustrate the Golgi apparatus in cell diagrams?

Arrows indicating its action Signup and view all the answers

Which of the following statements is true regarding plasma cells?

They play a key role in antibody production. Signup and view all the answers

What characterizes the Golgi apparatus in plasma cells?

It is prominent and well-developed. Signup and view all the answers

What type of cells primarily do not circulate in peripheral blood?

Plasma cells Signup and view all the answers

Why is the Golgi apparatus significant in the immune response?

It processes and packages antibodies before secretion. Signup and view all the answers

In which cellular structure is the Golgi apparatus highlighted as a key feature?

Cell diagrams Signup and view all the answers

What is one of the key processes facilitated by the Golgi apparatus in plasma cells?

Packaging of antibodies Signup and view all the answers

What is a primary distinguishing feature of plasma cells compared to other immune cells?

High levels of antibody production Signup and view all the answers

What is indicated by the presence of increased neutrophil precursors in peripheral blood?

Increased myeloid proliferation Signup and view all the answers

What is a common feature of a leukoerythroblastic reaction accompanied by immature RBCs?

Bone marrow infiltration Signup and view all the answers

What does a left shift in white blood cell differential typically suggest?

Increased myeloid proliferation Signup and view all the answers

What does an increase of band cells in peripheral blood imply?

Acute inflammatory response Signup and view all the answers

What is a potential underlying cause of a left shift where immature neutrophils are present?

Bone marrow infiltration diseases Signup and view all the answers

What is the primary role of platelets in hemostasis?

Involve in primary hemostasis Signup and view all the answers

Which hormone is responsible for stimulating megakaryocyte proliferation?

Thrombopoietin Signup and view all the answers

What condition results from thrombocytopenia or decreased platelet function?

Petechiae Signup and view all the answers

What characteristic describes the shape of platelets?

Anucleate, small cytoplasmic fragments Signup and view all the answers

Which of the following statements correctly describes megakaryocytes?

They give rise to platelets. Signup and view all the answers

What is a consequence of decreased platelet function?

Interruption in primary hemostasis Signup and view all the answers

Which process is essential for the formation of new megakaryocytes?

Thrombopoiesis Signup and view all the answers

What condition can lead to the appearance of petechiae on the skin?

Thrombocytopenia Signup and view all the answers

What is the main cellular origin of platelets?

Megakaryocytes Signup and view all the answers

In what way do platelets contribute to hemostasis?

By forming a plug at the site of injury Signup and view all the answers

What is the main effect of Lipid A binding to the CD14 receptor on macrophages?

Activation of macrophages to release pro-inflammatory cytokines Signup and view all the answers

Why is the immune response triggered by Lipid A considered crucial?

It helps fight infections effectively Signup and view all the answers

What serious condition can result from an overactive immune response due to Lipid A?

Septic shock Signup and view all the answers

Which statement best describes the outcomes of excessive pro-inflammatory cytokine release?

It can potentially lead to severe inflammation and organ failure. Signup and view all the answers

What characterizes septic shock?

A drastic drop in blood pressure and potential organ failure Signup and view all the answers

How does the activation of macrophages affect the immune response?

It triggers a release of cytokines that can promote inflammation. Signup and view all the answers

What is a potential negative consequence of a hyperactive immune response?

Tissue damage due to inflammation Signup and view all the answers

In what way can an overactive immune response impact blood pressure?

It can cause a drastic drop in blood pressure. Signup and view all the answers

Which of the following best explains the role of pro-inflammatory cytokines?

They are responsible for promoting inflammation. Signup and view all the answers

What happens when inflammation becomes widespread as a result of an overactive immune response?

It can result in systemic effects including organ failure. Signup and view all the answers

Study Notes

Energy Source in Red Blood Cells

Glucose serves as the primary energy source, with 90% utilized in glycolysis and 10% in the hexose monophosphate (HMP) shunt.
Membranes of red blood cells (RBCs) contain a Cl−/HCO3 − antiporter facilitating the export of HCO3 − and the transport of CO2 to the lungs for elimination.

Key Terminology

Erythrocytosis, also known as polycythemia, refers to an increased hematocrit (Hct).
Anisocytosis indicates the presence of varying sizes of cells.

Immune Cell Functions

RBCs can act as antigen-presenting cells via MHC II and are activated by IFN-γ.
They engage in antibody-dependent cellular cytotoxicity.
In granulomas (e.g., tuberculosis, sarcoidosis), RBCs can fuse to form giant cells.

Types of Macrophages

Kupffer cells are located in the liver.
Histiocytes are found in connective tissue.
Osteoclasts are present in bone.
Microglial cells reside in the brain.

Role in Sepsis

Lipid A, a component of lipopolysaccharide (LPS) from Gram-negative bacteria, binds to CD14 receptors on macrophages.
This binding triggers macrophages to release pro-inflammatory cytokines, crucial for infection response but can lead to severe inflammation.
Overactivity may result in septic shock, characterized by a significant drop in blood pressure and multiple organ failure.

Granulocytes Overview

Eosinophils: Defend against helminthic infections and prominently contain major basic protein (MBP).
Neutrophils: Acute inflammatory response cells, known for their multilobed nucleus and phagocytic capabilities.
Basophils: Mediate allergic reactions and contain densely basophilic granules rich in heparin and histamine.

Functions of Specific Granules

Eosinophils possess granules packed with large, uniform-sized granules and enzymes like leukocyte alkaline phosphatase (LAP), collagenase, and lactoferrin.
Neutrophils feature azurophilic granules crucial for combating pathogens.
Basophils can synthesize and release leukotrienes as needed.

Dendritic Cells

Function as highly phagocytic antigen-presenting cells (APCs).
Serve as a link between innate and adaptive immune systems, stimulating T-cell responses.
Express MHC class II and Fc receptors, capable of presenting exogenous antigens on MHC class I through cross-presentation.

Erythrocytes and Reticulocytes

Poikilocytosis indicates the presence of varying shapes of red blood cells (RBCs).
Reticulocytes are immature RBCs that serve as indicators of erythroid proliferation in the bone marrow.
A bluish color, termed polychromasia, is observed in reticulocytes on Wright-Giemsa stain, indicating residual ribosomal RNA.

Monocytes

Monocytes circulate in the blood and can differentiate into macrophages upon entering tissues.
Lipid A binding to CD14 receptors on macrophages activates these cells, inducing the release of pro-inflammatory cytokines.
This activation is essential for fighting infections but can lead to overactive responses, resulting in systemic inflammation and conditions like septic shock, characterized by a significant drop in blood pressure and multiple organ failure.

Megakaryocytes and Platelets

Megakaryocytes are the source of platelets, which play a crucial role in primary hemostasis.
Thrombopoietin stimulates the proliferation of megakaryocytes, enhancing platelet production.
Thrombocytopenia, or decreased platelet function, results in symptoms like petechiae.
Platelets are anucleate, small cytoplasmic fragments derived from megakaryocytes, crucial for blood clotting.

Plasma Cells

Plasma cells feature a well-rounded Golgi apparatus, vital for processing and packaging antibodies before secretion.
The prominence of the Golgi apparatus is often highlighted in cell diagrams to indicate its importance in antibody production.

Bone Marrow and Peripheral Blood

Megakaryocytes and plasma cells are primarily located in the bone marrow and do not circulate in peripheral blood.

Left Shift in Blood

A left shift refers to an increase in neutrophil precursors, such as band cells and metamyelocytes, in peripheral blood, indicating acute myeloid proliferation.
It often reflects conditions like inflammation or Chronic Myeloid Leukemia (CML).
Leukoerythroblastic reaction includes a left shift accompanied by immature RBCs, suggesting bone marrow infiltration due to conditions like myelofibrosis or metastasis.

Studying That Suits You

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

Description

This quiz covers the metabolic processes where glucose serves as the primary source of energy, focusing on glycolysis and the HMP shunt. Test your understanding of energy production and the significance of glucose in cellular respiration.