Which one of the following is the Structure of a cardiac muscle cell ?
Cylindrical, Branched and Uninucleate
Let's analyze the structure of cardiac muscle cells, also known as cardiomyocytes, which are the specialized muscle cells found in the heart.
Cardiac muscle is one of the three types of muscle tissue in the body, along with skeletal muscle and smooth muscle. Its unique structure is specifically adapted for its function: pumping blood rhythmically and continuously throughout life.
Understanding Cardiac Muscle Cell Structure
To answer the question about the structure of a cardiac muscle cell, let's look at its key characteristics:
- Shape: Cardiac muscle cells are typically described as cylindrical, or sometimes rectangular. They are shorter and wider than skeletal muscle fibers.
- Branching: A distinctive feature of cardiac muscle cells is that they are branched. These branches connect with neighboring cardiac muscle cells, forming a network. These connections occur at specialized junctions called intercalated discs, which allow for rapid communication and coordinated contraction.
- Nuclei: Cardiac muscle cells are generally uninucleate, meaning each cell usually contains only one nucleus. However, some may have two nuclei (binucleate), but they are not multinucleate like skeletal muscle fibers.
So, the structure of a typical cardiac muscle cell is cylindrical, branched, and uninucleate.
Analyzing the Options
Let's evaluate the given options based on our understanding of cardiac muscle cell structure:
- Option 1: Cylindrical, Unbranched and Multinucleate. This is incorrect because cardiac muscle cells are branched and typically uninucleate, not multinucleate.
- Option 2: Spinal shaped, Unbranched and Uninucleate. This is incorrect because cardiac muscle cells are cylindrical (or rectangular) and branched, not spinal shaped and unbranched. Spinal shaped cells are characteristic of smooth muscle.
- Option 3: Spinal shaped, Branched and Uninucleate. This is incorrect because cardiac muscle cells are cylindrical (or rectangular), not spinal shaped.
- Option 4: Cylindrical, Branched and Uninucleate. This option accurately describes the typical structural features of a cardiac muscle cell: cylindrical shape, presence of branches, and usually a single nucleus.
Based on the analysis, Option 4 correctly describes the structure of a cardiac muscle cell.
Summary of Cardiac Muscle Structure
Here is a brief summary comparing cardiac muscle to other muscle types based on the characteristics discussed:
| Feature | Skeletal Muscle | Smooth Muscle | Cardiac Muscle |
|---|---|---|---|
| Shape | Cylindrical | Spindle-shaped | Cylindrical / Rectangular |
| Branching | Unbranched | Unbranched | Branched |
| Nuclei per cell | Many (Multinucleate) | One (Uninucleate) | One or Two (Uninucleate/Binucleate) |
| Striations | Yes | No | Yes |
| Control | Voluntary | Involuntary | Involuntary |
This table highlights the unique combination of features found in cardiac muscle cells compared to other muscle types.
Revision Table: Key Muscle Tissue Differences
| Muscle Type | Structure | Location | Control |
|---|---|---|---|
| Skeletal | Striated, cylindrical, multinucleate, unbranched | Attached to bones | Voluntary |
| Smooth | Non-striated, spindle-shaped, uninucleate, unbranched | Walls of hollow organs (intestines, blood vessels, etc.) | Involuntary |
| Cardiac | Striated, cylindrical/rectangular, uninucleate (or binucleate), branched, intercalated discs | Heart wall | Involuntary |
Additional Information: Cardiac Muscle Cell Function
Beyond structure, the function of cardiac muscle cells is crucial. The branching nature and intercalated discs allow for rapid electrical impulse transmission from one cell to another. This synchronized electrical activity leads to coordinated contraction of the heart muscle, enabling efficient pumping of blood. The involuntary nature means the heart beats without conscious control, regulated by the autonomic nervous system.
The striations visible in cardiac muscle are due to the organized arrangement of contractile filaments (actin and myosin), similar to skeletal muscle, which allows for strong contractions. However, unlike skeletal muscle, cardiac muscle has a high density of mitochondria to meet its continuous energy demands.
Similar Questions
Which one of the following is the correct sequence of organs that occur in the path of urine flow in human body?
Which one of the following cell organelles mainly functions as storehouse of digestive enzymes?
The causal organism of dengue fever is a mosquito-borne virus which belongs to which one among the following categories?
Which of the following statements is/are correct about vaccination that provides
protection against an infectious disease?1. It blocks the entry of the infectious agent into body.
2. It produces antibodies against infection.
3. It kills the infectious agent when it enters in the body.
Select the correct answer using the code given below.
AIDS is caused by the Human Immunodeficiency Virus (HIV). The transmission of HIV infection generally occurs through
In human body, the cell growth and differentiation are highly controlled and regulated, but in cancer cells
The mammalian heart is myogenic, and it is regulated by nerves. The heartbeat originates from
Which one of the following hormones contains peptide chain?
Which one of the following statements is correct?
Which one of the following body parts/organs of the human body does not have smooth muscles?
Important Questions from Human body
A resting person, usually has a pulse rate between ______ and ______ beats per minute
In humans, neck and head are joined by which joint ?
The human skeleton is composed of around ______ bones at birth.
At which period of life, body undergoes changes leading to reproductive maturity?
Milk is no longer called a balanced diet due to the lack of which one of the following?
