Question 1: Define the term 'reflex arc' and explain its importance in the nervous system.

Answer: A reflex arc is a rapid, automatic nerve response that bypasses the brain to enable quick reactions. It is important for protecting the body from harm and maintaining homeostasis.

Question 2: Describe how nanotechnology can be utilised to enhance the sensitivity of reflex responses in medical devices.

Answer: Nanotechnology can be used to develop nanosensors that detect stimuli at a molecular level, allowing for faster and more precise reflex responses in medical implants or robotic systems.

Question 1: What are the main components of a reflex arc?

Answer: Receptor, sensory neurone, relay neurone (sometimes), motor neurone, effector.

Question 2: Explain how nanotechnology can improve the speed of nerve signal transmission in artificial reflex systems.

Answer: Nanomaterials can be used to create highly conductive and responsive interfaces that facilitate faster electrical signal transmission between sensors and actuators, mimicking natural reflex speeds.

Question 1: If a nanosensor detects a stimulus within 0.001 seconds and transmits the signal over a distance of 2 cm with a speed of 3 x 10^8 m/s, calculate the time taken for the signal to reach the processing unit. Show your working and give your answer in milliseconds.

Answer: Time = Distance / Speed = 0.02 m / (3 x 10^8 m/s) = 6.67 x 10^-11 seconds. Since this is negligible compared to detection time, total response time remains approximately 0.001 seconds or 1 millisecond.

Question 1: Design a basic experiment to evaluate the sensitivity of a nanotechnology-enabled reflex sensor to a chemical stimulus. Identify independent, dependent, and control variables, and outline safety precautions.

Answer: The experiment involves exposing the nanosensor to varying concentrations of the chemical and recording the detection time. Independent variable: chemical concentration; dependent variable: detection time; control variables: temperature, humidity, sensor type. Safety precautions include wearing gloves, lab coat, eye protection, and working in a well-ventilated area to prevent chemical exposure and nanoparticle inhalation.

Question 1: A company has developed a nanotech-based device that instantly triggers a protective response when detecting a corrosive chemical. The device's response time is measured at 0.0002 seconds. Explain how the reflex arc principles are applied in this device and why nanotechnology is crucial for its performance.

Answer: The device mimics the natural reflex arc by detecting the chemical via a nanosensor, which rapidly transmits an electrical signal to a controller that activates a protective mechanism. Nanotechnology is crucial because it enables extremely fast detection and signal transmission due to high sensitivity and conductivity at the nanoscale, ensuring immediate response to prevent damage.

Question 1: Discuss the potential advantages and challenges of integrating nanotechnology into the natural reflex arc system to improve human safety and response times. Include at least three points for each side.

Answer: Advantages include: (1) Faster response times due to nanosensors and conductive nanomaterials; (2) Enhanced sensitivity to stimuli; (3) Potential for customisation for specific responses. Challenges include: (1) Possible toxicity or environmental impact of nanoparticles; (2) High costs of nanotechnology development; (3) Difficulties in ensuring biocompatibility and long-term stability within the human body.