BIOLOGY 2401 UPDATED EXAMINERS 2026
QUESTIONS AND ANSWERS SURE A+
✔✔Describe the Process going from the Stimulus to the Effector - ✔✔When something
happens it is called a Stimulus, a change in variable. The change is picked up by the
receptor, usually a sensory neuron. Then it carries the information to a control center.
The control center decide what needs to be done to return the body to Homeostasis.
The control center sends a command to the Effector.
✔✔Difference Between Positive and Negative Feedback - ✔✔Negative Feedback: Will
try to bring itself down.
Positive Feedback: Will continue until the climatic point is reached.
✔✔Example of Negative Feedback - ✔✔Body Temperature Regulation: If the body's
temperature drops, the body will begin to shiver in an attempt to warm the body up. If
the body temperature raises, the body will sweat to cool down due to evaporation.
✔✔Example of Positive Feedback - ✔✔Childbirth, Contractions, and Lactating
In giving birth, contractions will continue until the Climatic Point is reached.
✔✔Types of medical imaging - ✔✔Radiography-x rays, High Energy Radiation that
penetrates solid structures in the body. Mostly for bones, teeth, and tumors.
, MRI-Uses strong magnetic field and radios waves to release energy which can be
visualized. Good for soft tissues.
CT Scan (Computed Tomography)-Low intensity x-rays (little), slices that make 3D
images, Good for Tumors, aneurysms, and Kidney Stones.
Sonography-AKA Ultrasound. Waves reflects organs-Sonogram.
PET Scan (Position Emission Tomography)-Injection of radioactively labeled glucose.
Can detect metabolic activity in tissues, can detect tumors and metastasis.
✔✔Best Medical Imaging for Bones - ✔✔Radiography (X-Ray)
✔✔Best Medical Imaging for Fetus - ✔✔Sonography (Sonogram)
✔✔Best Medical Imaging for Tumors - ✔✔Radiography (X-Ray) or a CT Scan
✔✔Best Medical Imaging for Soft Tissues - ✔✔Position Emission Tomography (PET
Scan)
✔✔Best Medical Imaging for Teeth - ✔✔Radiography (X-Ray)
✔✔Best Medical Imaging for Kidney Stones - ✔✔Computed Tomography (CT Scan)
✔✔Best Medical Imaging for Tumor Metastasis - ✔✔Position Emission Tomography
(PET Scan)
✔✔Describe an Atom - ✔✔Is the smallest particle that exhibits the chemical properties
of an element.
✔✔The Components of an Atom are: - ✔✔Neutrons ( No Charge) located inside the
Nucleus
Protons (+Charge) located inside the Nucleus
Electrons (-Charge) located outside the Nucleus
✔✔The most common elements of the human body are: - ✔✔Oxygen
Carbon
Hydrogen
Nitrogen
Calcium
Phosphorus
✔✔What is an ion? - ✔✔atoms that have gained or lost electrons
✔✔What is it called when an ion has a Positive Charge? - ✔✔Cation
QUESTIONS AND ANSWERS SURE A+
✔✔Describe the Process going from the Stimulus to the Effector - ✔✔When something
happens it is called a Stimulus, a change in variable. The change is picked up by the
receptor, usually a sensory neuron. Then it carries the information to a control center.
The control center decide what needs to be done to return the body to Homeostasis.
The control center sends a command to the Effector.
✔✔Difference Between Positive and Negative Feedback - ✔✔Negative Feedback: Will
try to bring itself down.
Positive Feedback: Will continue until the climatic point is reached.
✔✔Example of Negative Feedback - ✔✔Body Temperature Regulation: If the body's
temperature drops, the body will begin to shiver in an attempt to warm the body up. If
the body temperature raises, the body will sweat to cool down due to evaporation.
✔✔Example of Positive Feedback - ✔✔Childbirth, Contractions, and Lactating
In giving birth, contractions will continue until the Climatic Point is reached.
✔✔Types of medical imaging - ✔✔Radiography-x rays, High Energy Radiation that
penetrates solid structures in the body. Mostly for bones, teeth, and tumors.
, MRI-Uses strong magnetic field and radios waves to release energy which can be
visualized. Good for soft tissues.
CT Scan (Computed Tomography)-Low intensity x-rays (little), slices that make 3D
images, Good for Tumors, aneurysms, and Kidney Stones.
Sonography-AKA Ultrasound. Waves reflects organs-Sonogram.
PET Scan (Position Emission Tomography)-Injection of radioactively labeled glucose.
Can detect metabolic activity in tissues, can detect tumors and metastasis.
✔✔Best Medical Imaging for Bones - ✔✔Radiography (X-Ray)
✔✔Best Medical Imaging for Fetus - ✔✔Sonography (Sonogram)
✔✔Best Medical Imaging for Tumors - ✔✔Radiography (X-Ray) or a CT Scan
✔✔Best Medical Imaging for Soft Tissues - ✔✔Position Emission Tomography (PET
Scan)
✔✔Best Medical Imaging for Teeth - ✔✔Radiography (X-Ray)
✔✔Best Medical Imaging for Kidney Stones - ✔✔Computed Tomography (CT Scan)
✔✔Best Medical Imaging for Tumor Metastasis - ✔✔Position Emission Tomography
(PET Scan)
✔✔Describe an Atom - ✔✔Is the smallest particle that exhibits the chemical properties
of an element.
✔✔The Components of an Atom are: - ✔✔Neutrons ( No Charge) located inside the
Nucleus
Protons (+Charge) located inside the Nucleus
Electrons (-Charge) located outside the Nucleus
✔✔The most common elements of the human body are: - ✔✔Oxygen
Carbon
Hydrogen
Nitrogen
Calcium
Phosphorus
✔✔What is an ion? - ✔✔atoms that have gained or lost electrons
✔✔What is it called when an ion has a Positive Charge? - ✔✔Cation
