Question

____ consists mainly of plasma. A. Areolar connective tissue B. Blood C. Cartilage D. Bone

Short answer

The correct answer is B. Blood.

Step-by-step solution

Understanding Plasma

Plasma is the liquid component of blood, consisting mostly of water, proteins, nutrients, hormones, and waste products. It makes up about 55% of the body’s total blood volume.

Analyzing Each Option

Let's analyze each option in the context of plasma: - Areolar connective tissue is a type of loose connective tissue that supports and binds other tissues, but it does not consist mainly of plasma. - Blood is composed of plasma and cells (red blood cells, white blood cells, platelets). - Cartilage is a flexible connective tissue that doesn't contain plasma. - Bone is a dense structural tissue that does not contain plasma.

Identifying the Correct Answer

Since plasma is specifically a component of blood, blood is the correct answer. Blood consists mainly of plasma, making option B the right choice.

Key concepts

Plasma

Plasma is an essential component of human blood and plays a crucial role in the circulatory system. It is a yellowish liquid that makes up about 55% of the total blood volume. Plasma is primarily composed of water, allowing it to transport various substances throughout the body. Alongside water, it contains proteins, such as albumin, globulins, and fibrinogen, which are vital for maintaining oncotic pressure and blood clotting functions. Additionally, plasma carries nutrients like glucose, minerals such as electrolytes, and waste products like urea to be excreted. It also serves as a medium for hormones and vitamin transportation. Because plasma is mostly water, it helps regulate body temperature and maintain blood pressure stability.

Blood Composition

Blood is a vital fluid in the human body, and it's composed of various elements that work together to sustain life. While plasma accounts for the majority of blood, approximately 55%, the rest is made up of

• Red blood cells (erythrocytes): These cells contain hemoglobin, a protein that transports oxygen from the lungs to all parts of the body and CO2 back to the lungs for exhalation.
• White blood cells (leukocytes): They are part of the immune system and help the body fight off infections.
• Platelets (thrombocytes): These are responsible for blood clotting, preventing excessive bleeding.

This intricate composition ensures that blood can perform its essential duties—such as nutrient delivery, waste removal, and immune response—efficiently. Understanding blood composition is fundamental for recognizing how oxygen and critical nutrients are circulated throughout the body.

Connective Tissues

Connective tissues play a vital role in providing structural support, connecting different tissues, and protecting body organs. They are composed of cells, fibers, and a varying amount of ground substance. The most common types of connective tissues include:

• Areolar tissue: A loose connective tissue that holds organs in place and attaches epithelial tissues to other underlying tissues.
• Adipose tissue: Stores fat and serves as an energy reserve, cushioning, and insulation for the body.
• Dense connective tissue: Such as tendons and ligaments, provides strong attachment and high tensile strength.
• Cartilage: This flexible tissue reduces friction between bones and supports them.
• Bone: The rigid structure providing support and protection to the body.

Connective tissues are diverse, with varying properties that suit their functions—whether it's providing elasticity, strength, or shock absorption.

Body Fluids

Body fluids are essential components of the body's internal environment. They include fluids within cells, known as intracellular fluids, and those outside the cells, termed extracellular fluids. Plasma is a significant part of extracellular fluid, playing a critical role in nutrient transportation and waste removal. Other extracellular fluids include:

• Interstitial fluid: Fills the space between most of the cells of the body, cushioning them and allowing the exchange of nutrients and waste.
• Lymph: A fluid that is part of the lymphatic system, which helps in removing toxins and waste from the body.

These body fluids ensure that cells maintain homeostasis by providing a stable environment for cellular functions. They are integral to multiple bodily processes, including digestion, absorption, circulation, and excretion.