Nokea
Vertebrate eyes are Single-lens eyes with
- A. Light is focused by the curved cornea and lens
- B. Changing the shape of the lens focuses near and far
- C. Photoreceptor cells in the retina detect light
- D. All above
Correct Answer: D
Rationale: The correct answer is D because vertebrate eyes have single-lens eyes where light is focused by the curved cornea and lens (A), and changing the shape of the lens allows for focusing at different distances (B). Additionally, photoreceptor cells in the retina detect light (C). Therefore, all of the above statements are true, making D the correct choice. Choice A is incorrect because it does not encompass the entire process of vision in vertebrate eyes, missing the role of changing the lens shape. Choice B is incorrect as it only addresses the lens shape without mentioning the role of the cornea in focusing light. Choice C is incorrect as it only focuses on the function of photoreceptor cells in the retina without considering the lens and cornea's role in focusing light.
You may also like to solve these questions
T cells can recognize
- A. Linear peptides
- B. The shape of antigens
- C. Buried epitopes
- D. Soluble antigens
Correct Answer: B
Rationale: The correct answer is B: The shape of antigens. T cells recognize antigens based on their shape, specifically the conformational structure of the antigen. T cell receptors interact with the surface of antigens, forming a complex based on the shape complementarity. This interaction is crucial for T cell activation and immune response.
A: Linear peptides - While T cells can recognize linear peptides presented by MHC molecules, the primary mode of recognition is through the shape of antigens.
C: Buried epitopes - T cells typically recognize epitopes displayed on the surface of antigens rather than buried within the structure.
D: Soluble antigens - T cells can recognize both soluble and membrane-bound antigens, but the key factor is the shape rather than the solubility of the antigen.
Which of the following is NOT an example of a pathogen-associated molecular pattern (PAMP)?
- A. Lipopolysaccharide (LPS)
- B. Peptidoglycan
- C. Viral RNA
- D. MHC molecules
Correct Answer: D
Rationale: The correct answer is D, MHC molecules. PAMPs are conserved molecules found on pathogens that can trigger an immune response. MHC molecules are not PAMPs; they are part of the host's immune system used to present antigens to T cells. LPS, peptidoglycan, and viral RNA are examples of PAMPs as they are specific molecules found on pathogens that can be recognized by pattern recognition receptors on immune cells to initiate an immune response.
A 69-year-old woman asks the nurse whether it is possible to 'catch' cancer because many of her friends of the same age have been diagnosed with different kinds of cancer. In responding to the woman, the nurse understands that what factor increases the incidence of tumors in older adults?
- A. An increase in autoantibodies
- B. Decreased activity of the bone marrow
- C. Decreased differentiation of T lymphocytes
- D. Decreased size and activity of the thymus gland
Correct Answer: D
Rationale: The thymus gland shrinks with age, reducing the production of new T cells, which impairs immune surveillance and increases cancer risk.
A client is being administered the first dose of belimumab for a systemic lupus erythematosus flare. What actions by the nurse are most appropriate? (Select one that does not apply.)
- A. Observe the client for at least 2 hours afterward.
- B. Instruct the client about the monthly infusion schedule.
- C. Inform the client not to drive or sign legal papers for 24 hours.
- D. Ensure emergency equipment is working and nearby.
Correct Answer: C
Rationale: The correct answer is C: Inform the client not to drive or sign legal papers for 24 hours. This is because belimumab can cause dizziness and fatigue as side effects, which may impair the client's ability to drive or make important decisions. It is crucial for the nurse to ensure the safety of the client and others by advising against these activities for 24 hours post-administration.
Choice A: Observing the client for at least 2 hours is important for monitoring immediate adverse reactions, but it is not the most appropriate action in this scenario.
Choice B: Instructing the client about the monthly infusion schedule is important for treatment adherence, but it is not the most immediate concern after the first dose administration.
Choice D: Ensuring emergency equipment is working and nearby is important for safety precautions, but advising the client not to drive or sign legal papers is more directly related to the potential side effects of belimumab.
T-cell antigen receptors are distinguished from antibodies by which of the following
- A. T-Cell receptors are glycosylated
- B. T-cell receptors must interact with antigen uniquely presented by other cells but not with free antigen
- C. T-Cell receptors bind various cytokines
- D. T-Cell receptors bind complement to lyse cells
Correct Answer: B
Rationale: The correct answer is B. T-cell receptors must interact with antigens uniquely presented by other cells but not with free antigen. This is because T-cell receptors recognize antigens that are processed and presented on the surface of other cells via major histocompatibility complex (MHC) molecules. T-cell receptors specifically bind to the antigen-MHC complex, allowing T-cells to respond to specific foreign antigens.
A: T-cell receptors are not distinguished from antibodies by glycosylation. Both T-cell receptors and antibodies can be glycosylated, so this does not differentiate them.
C: T-cell receptors do not bind various cytokines. Cytokine receptors are separate entities that mediate cellular responses to cytokines.
D: T-cell receptors do not bind complement to lyse cells. Complement activation is a separate immune response mechanism not involving T-cell receptors.