Question

regents questions
directions: answer the questions below using your notes and knowledge of biology

1. some human white blood cells help destroy pathogenic bacteria by

(1) causing mutations in the bacteria (3) producing toxins that compete with bacterial toxins
(2) engulfing and digesting the bacteria (4) inserting part of their dna into the bacterial cells

1. certain microbes can cause immune responses in the body because they contain

(1) antigens (2) enzymes (3) fats (4) cytoplasm

1. the diagram below represents what can happen when homeostasis in an organism is threatened. which statement provides a possible explanation for these events?

(1) antibiotics break down harmful substances by the process of digestion.
(2) antibodies mark and other cells engulf microbes during immune reactions.
(3) embryonic development of essential organs occurs during pregnancy.
(4) cloning removes abnormal cells produced during differentiation.

1. describe the role of white blood cells in maintaining homeostasis in organisms.

(hint- this should include 2 different functions of the white blood cell!)

1. which statement best describes an immune response?

(1) it always produces antibiotics.
(2) it involves recognition and destruction of pathogens.
(3) it stimulates asexual reproduction in pathogens.
(4) it releases red blood cells that destroy parasites.

1. both antibodies and antibiotics can help a human maintain homeostasis. however, students often confuse these two terms. provide an explanation of what how antibodies help maintain homeostasis and how antibiotics can help maintain homeostasis.

1. which of the following best describes an antigen?

(1) it is a protein produced by white blood cells which binds to the surface of pathogens
(2) it is a protein located on pathogens
(3) it is a substance that binds to antibiotics
(4) it is a substance that kills bacteria

1. identify the body system responsible for fighting off sickness

Explanation:

1. Phagocytes (a type of white blood cell) engulf and digest pathogens (like bacteria) through phagocytosis. Mutations in bacteria by white blood cells aren't a common destruction mechanism. White blood cells don't produce toxins to compete with bacterial toxins in the described way, and they don't insert their DNA into bacterial cells.
2. Antigens are substances (often on the surface of microbes) that trigger an immune response. Enzymes, fats, and cytoplasm of microbes don't typically cause immune responses in the way antigens do.
3. The diagram likely represents immune reactions. Antibiotics are external substances (not produced by the body in the context of the diagram's implied immune - related process). Embryonic development and cloning are not related to the depicted immune - like process. Antibodies mark pathogens (for example, through opsonization) and other cells (like phagocytes) engulf the marked microbes.
4. White blood cells (leukocytes) have multiple functions. Some white blood cells (like macrophages) engulf and destroy pathogens (phagocytosis). Others (like lymphocytes - B cells and T cells) produce antibodies (in the case of B cells) or coordinate the immune response (T cells).
5. An immune response is about recognizing (through receptors on immune cells that bind to antigens) and destroying (through various mechanisms like phagocytosis, antibody - mediated lysis) pathogens. It doesn't always produce antibiotics (which are often external substances), doesn't stimulate asexual reproduction in pathogens, and red blood cells are for oxygen transport, not destroying parasites in the context of the main immune response description.
6. Antibodies are proteins produced by B lymphocytes. They bind to antigens on pathogens. This can mark the pathogen for destruction (opsonization), neutralize toxins (if the pathogen produces toxins and the antibody binds to the toxin), or cause agglutination (clumping) of pathogens. Antibiotics are substances (either produced by other organisms or synthetic) that kill or inhibit the growth of bacteria. For example, penicillin inhibits bacterial cell wall synthesis.
7. An antigen is a substance (often a protein or carbohydrate) located on pathogens (or other foreign cells). The protein produced by white blood cells that binds to pathogen surfaces is an antibody. Antigens don't bind to antibiotics in the way described, and they don't kill bacteria (that's more of an antibiotic or some immune cell - mediated lysis function).
8. The immune system is responsible for fighting off sickness. It includes cells (like white blood cells), tissues (like lymph nodes), and organs (like the spleen) that work together to recognize and eliminate pathogens.

Answer:

1. (2)
2. (1)
3. (2)
4. White blood cells engulf and destroy pathogens (phagocytosis) and some produce antibodies to mark pathogens for destruction.
5. (2)
6. Antibodies bind to antigens on pathogens to mark them for destruction, neutralize toxins, or cause agglutination. Antibiotics kill or inhibit bacterial growth (e.g., by interfering with cell wall synthesis).
7. (2)
8. The immune system.