immunity test 3

Detailed Hint:

• When it comes to cellular structures, it is crucial to recognize the distinct components of each cell type.
• Cellulose is primarily found in plant cell walls, while chitin is a major component of fungal cell walls.
• However, the cell wall of a prokaryotic bacterial cell is predominantly composed of a substance called Murein, which is chemically known as Peptidoglycan.
• Peptidoglycan consists of Amino acids (Peptido) and Carbohydrates (Glycan).
• Therefore, the correct answer is C, "Murein".

Short Hint: The nose and nasal cavity play integral roles in ensuring each breath is filtered, warmed, and moisturized. They filter airborne particles, warm the air to match body temperature, and moisturize it to protect delicate lung tissues.

Short Hint: Organisms have defense mechanisms to protect themselves, and one such mechanism involves producing antibodies. Antibodies are proteins that the immune system uses to neutralize pathogens such as bacteria and viruses.

Short Hint: Perforin is a protein that the immune cells use to punch holes in the membranes of foreign cells. It contains protease, an enzyme that helps break down proteins.

Short Hint: Antibody-mediated immunity is a critical component of the body's immune response, primarily facilitated by B cells. T cells are responsible for cell-mediated immunity, while platelets play a significant role in blood clotting.

Short Hint: The body's immunity system has several lines of defense against foreign invaders, with the second line being nonspecific in nature. This includes the inflammatory response, fever, and phagocytosis, which are not tailored to any specific pathogen.

Short Hint: The first line of defense in the immune system includes physical and chemical barriers like skin, mucus membranes, and secretions from ear, eyes, nose, mouth. Pyrexia, or fever, is considered part of the second line of defense, as it is a nonspecific systemic response to infection.

Detailed Hint:

Epidermal dendritic cells are a type of antigen-presenting cells that play an essential role in the immune system.

They are predominantly found in the skin where they actively patrol and phagocytize pathogens.

Detailed Hint:

Interferons are a group of signaling proteins that are produced and released by host cells in response to the presence of several viruses.

They help neighboring cells resist viral infections, increasing their resistance to viral replication.

Detailed Hint:

Memory cells are a crucial component of the adaptive immune system, providing long-term immunity.

They are derived from both T cells and B cells. These cells remain in the body after an immune response and quickly respond to subsequent encounters with the same antigen.

Detailed Hint:

The skin's acidity, also known as the acid mantle, is a product of the secretions from the sebaceous glands.

These secretions create an environment that is unfavorable for many types of bacteria, reducing their ability to thrive.

Detailed Hint:

The first line of defense in the body includes a range of physical and chemical barriers.

This incorporates the skin, mucous, and tiny hairs that help to trap and prevent the entry of pathogens.

Detailed Hint:

A healthy stomach typically exhibits an acidic environment due to the secretion of gastric juices.

It is also sterile and acts as an antiseptic, killing or inhibiting the growth of bacteria ingested with food.

Detailed Hint:

Monocytes are a type of white blood cell that circulates in the blood.

In their immature form, they are known as macrophages, which play a critical role in the immune response by phagocytizing harmful substances.

Detailed Hint:

The skin has several key functions in maintaining the body's homeostasis and immunity.

It prevents excessive water loss, provides insulation, and serves as the first line of defense against pathogens and environmental threats.

Detailed Hint:

The body's defense mechanisms are divided into non-specific (innate) and specific (adaptive) immunity.

The first and second lines of defense are non-specific and act regardless of the type of pathogen, while the third line of defense is specific and tailors its response to individual pathogens.

Detailed Hint:

Sebum, a substance secreted by the sebaceous glands in the skin, contributes to the skin's acidity.

This acidic nature helps in creating an environment that is not conducive for many types of bacteria to thrive.

Detailed Hint:

Antigen-presenting cells (APCs) are a type of immune cell that ingests, processes, and presents antigens to T-cells.

Both B cells and macrophages act as APCs, each playing a crucial role in triggering the body's immune response.

Detailed Hint:

The second line of defense comes into action when pathogens successfully penetrate the first line of defense, such as the skin.

This includes mechanisms like inflammation, fever, and phagocytosis that target intruding pathogens irrespective of their type.

Detailed Hint:

T cells and B cells are both types of lymphocytes involved in the body's immune response.

While both types have receptor sites, only T cells undergo maturation in the thymus. B cells, on the other hand, mature in the bone marrow.

Detailed Hint:

The immune system comprises various types of T cells, each with a unique function.

Cytotoxic T cells are primarily responsible for eliminating cells infected by viruses.

Helper T cells assist other immune cells, while suppressor T cells regulate immune responses.

Detailed Hint:

• When it comes to cellular structures, it is crucial to recognize the distinct components of each cell type.
• Cellulose is primarily found in plant cell walls, while chitin is a major component of fungal cell walls.
• However, the cell wall of a prokaryotic bacterial cell is predominantly composed of a substance called Murein, which is chemically known as Peptidoglycan.
• Peptidoglycan consists of Amino acids (Peptido) and Carbohydrates (Glycan).
• Therefore, the correct answer is C, "Murein".

Detailed Hint:

• The body's physiological condition can be affected by various abnormalities in blood cell counts.
• Polycythemia refers to a condition where there is an increased number of red blood cells.
• This is different from leukemia (increased white blood cells), edema (swelling from fluid build-up), and anemia (decreased red blood cells).

Detailed Hint:

• The immune system in humans is categorized into three lines of defense.
• It includes the physical barriers (first line), the innate immune system (second line), and the adaptive immune system (third line).
• It's designed this way to provide a series of defenses against potential pathogens.

Detailed Hint:

• Macrophages are large white blood cells that are an essential part of the immune system.
• They originate from monocytes, a type of white blood cell that circulates in the bloodstream.
• When monocytes enter tissues, they can differentiate into macrophages.

Detailed Hint:

• Epidermal dendritic cells are immune cells located in the skin.
• Their primary function is to phagocytize or engulf and digest pathogens.
• They are a part of the skin's immune defense, helping to maintain the body's overall health.

Detailed Hint:

• The immune system employs different types of cells to combat harmful entities.
• CD8 cells, also known as cytotoxic T cells, have the ability to kill infected cells.
• Similarly, Natural Killer cells (NK) are known for their cytotoxic properties, i.e., they can kill tumor cells or virus-infected cells.
• However, while macrophages perform important functions in the immune system, they are not typically considered cytotoxic.

Detailed Hint:

• Collagen is a robust and fibrous protein that plays an essential role in connecting tissues.
• It is abundant in the dermis, bones, cartilage, and the cornea of the eye.
• However, it's not found in hair and nails as these structures are primarily composed of a protein called keratin.

Detailed Hint:

• White blood cells, or leukocytes, are a vital part of the immune system and are found in varying amounts in the body.
• Neutrophils are the most abundant type of white blood cells in humans.
• They are the first line of defense when infection occurs, and they respond quickly to the site of infection.

Detailed Hint:

Sebum is an oily substance produced by the skin's sebaceous glands.

It plays a crucial role in maintaining the skin's health, including the inhibition of harmful bacteria.

One of its functions is lowering the skin's pH, which creates a hostile environment for bacteria, thus curbing their growth.

Detailed Hint:

T cells are a type of white blood cell that are critical to the immune response.

They are responsible for cell-mediated immunity, targeting and destroying infected cells.

They mature in the thymus, which is a gland located behind the sternum and between the lungs.

They also play a role in modulating the immune response by stimulating and suppressing B cells.

Detailed Hint:

The immune system responds to foreign substances in the body to maintain health.

These foreign substances, which provoke an immune response, are referred to as antigens.

Antigens can originate from various sources, including viruses, bacteria, and allergens.

Detailed Hint:

The immune system is a complex network of cells and proteins that defends the body against infection.

One of its primary roles is to identify and eliminate pathogens like bacteria, viruses, and other foreign bodies.

The immune system can also recognize and destroy abnormal cells that have originated from host tissues, including cancer cells.

Additionally, it can distinguish between the body's cells (self) and foreign cells (non-self).

Detailed Hint:

Sweat, produced by the sweat glands, has both cooling and antimicrobial functions.

Among the various components, it contains an enzyme called lysozyme.

Lysozyme is known for its ability to break down the cell walls of bacteria, thus acting as a natural defense against certain types of infections.

Detailed Hint:

The immune system's second line of defense is composed of both specific and non-specific immune responses.

This includes the action of macrophages, which engulf and digest pathogens and dead cells.

Natural Killer (NK) cells, another integral part of the second line of defense, can recognize and kill virus-infected cells and tumor cells.

Neutrophils, the most abundant type of white blood cells, respond quickly to the site of infection and are effective at killing bacteria.

Detailed Hint:

• The immune system is made up of several defense layers that protect the body from harmful pathogens.
• The first line of defense is made up of physical and chemical barriers, such as skin, mucus, hair, and stomach acid.
• Hydrochloric acid in the stomach serves to neutralize bacteria and other potential threats that could cause illness if ingested with food or drink.

Detailed Hint:

• The dermis layer of the skin houses various cells and structures, including fibrous proteins.
• Among these proteins, collagen plays a crucial role in providing structure and elasticity to the skin.
• Unlike lysozyme and myosin, which are enzymes and muscle proteins, respectively, collagen specifically contributes to the skin's resilience.

Detailed Hint:

• Sweat is a mixture of water, salts, and enzymes, and serves cooling and antimicrobial functions.
• Of those enzymes, lysozyme can break down bacterial cell walls, rendering them ineffective.
• Histamine, mucus, and hydrochloric acid serve different roles in the body and are not found in sweat.

Detailed Hint:

• Pyrexia, also known as a fever, is a common response of the body to infection.
• It activates the immune system and makes the internal environment unfavorable for the growth of pathogens.
• Contrary to increasing iron secretion, pyrexia actually suppresses it, as iron is a crucial element for bacterial growth.

Detailed Hint:

• Natural Killer (NK) cells are a type of white blood cell, specifically a lymphocyte.
• They play a crucial role in the immune system by identifying and killing abnormal cells, such as virus-infected cells and cancer cells.
• These cells are also cytotoxic, meaning they have the ability to kill other cells.

Detailed Hint:

• The skin serves as a physical barrier, defending the body against infection by harmful pathogens.
• It helps to prevent excessive loss of water and electrolytes from the body, contributing to homeostasis.
• The skin also plays a role in insulation, temperature regulation, and the perception of touch, pain, and temperature.