Problem 112 - Objective Biology for NEET

Question

Select the total number of incorrect matching from the following: (A) ECG-Electro Cardio Gram (B) AVN-Atrio Ventricular Node (C) SAN-Sino Atrial Node (D) WBC-White Blue Cells (E) RBC-Red Blood Cells (a) 1 (b) 2 (c) 3 (d) \(\overline{4}\)

Step-by-Step Solution

Answer

The total number of incorrect matches is one, which is option (a).

Step 1: Identifying Correct Matches

Firstly, identify the acronyms that are correctly matched with their terms. (A) ECG stands for Electro Cardio Gram - Correct (B) AVN stands for Atrio Ventricular Node - Correct (C) SAN stands for Sino Atrial Node - Correct (E) RBC stands for Red Blood Cells - Correct

Step 2: Identifying Incorrect Matches

Secondly, identify the acronym that is incorrectly matched with its term.(D) WBC does not stand for White Blue Cells. In fact, WBC stands for White Blood Cells. Therefore, (D) is incorrect.

Key Concepts

Electro Cardio Gram

The Electro Cardio Gram, commonly abbreviated as ECG, is a crucial medical tool used to measure the electrical activity of the heart over time. This procedure is non-invasive and captures the heart's activity by utilizing electrodes placed on the skin. The ECG records the electrical signals produced as the heart contracts and relaxes, helping to assess heart health and identify any unusual patterns.

ECG results are displayed as a graph with a series of waves and intervals. Each part of the ECG tracing represents a specific phase of the cardiac cycle:

• The P wave indicates atrial contraction.
• The QRS complex represents ventricular depolarization.
• The T wave reflects ventricular repolarization.

Understanding these patterns is vital for diagnosing various heart conditions.

Atrio Ventricular Node

The Atrio Ventricular Node, or AVN, plays a pivotal role in the heart's electrical conduction system. Located between the atria and ventricles, the AVN acts as a "gatekeeper" for electrical impulses. It slows down the electrical signal before it passes from the atria to the ventricles.

This delay is crucial as it ensures the atria have enough time to contract fully, thus optimizing the filling of the ventricles with blood before they contract. The controlled timing of these contractions supports efficient blood flow throughout the body and maintains proper heart rhythm.

Sino Atrial Node

Known as the heart's natural pacemaker, the Sino Atrial Node, or SAN, initiates the electrical signal that prompts the heart to beat. Located in the right atrium, it generates electrical impulses spontaneously, setting the rhythm for the heart.

These impulses travel through the atria, causing them to contract and push blood into the ventricles. The frequency of these electrical impulses, determined by the SAN, can increase or decrease based on the body's demands, such as during exercise or rest. This adaptability makes the SAN essential for regulating heart rate and ensuring that the heart responds appropriately to varying physiological needs.

White Blood Cells

White Blood Cells (WBCs) are a crucial component of the immune system. They are responsible for protecting the body against both infectious disease and foreign invaders. Unlike "White Blue Cells," a term inaccurately used in our exercise, WBCs play a key role in maintaining our health.

There are several types of white blood cells, each with specific functions:

• Neutrophils: The most common type, responsible for the destruction of bacteria and fungi.
• Lymphocytes: Critical for producing antibodies and regulating the immune response.
• Monocytes: Aid in breaking down bacteria.
• Eosinophils: Combat parasites and are involved in allergic reactions.
• Basophils: Release histamine during allergic reactions.

These cells work synergistically to detect and eliminate pathogens, keeping the body healthy.

Red Blood Cells

Red Blood Cells (RBCs), or erythrocytes, are essential for transporting oxygen from the lungs to the rest of the body and returning carbon dioxide to the lungs to be exhaled. They are characterized by their biconcave shape and the presence of hemoglobin, a protein that binds oxygen.

This unique shape increases their surface area, making them highly efficient at gas exchange. RBCs are produced in the bone marrow and have a lifespan of around 120 days. Their abundance makes them the most common type of blood cell, essential for maintaining cellular respiration, supporting energy production and overall cellular function.