1. The fatty sheath that insulates some nerve fibers and speeds up signal transmission is called the:

A. Myelin sheath
B. Dura mater
C. Pia mater
D. Arachnoid mater

Correct answer: A

Rationale: The correct answer is A: Myelin sheath. The myelin sheath is a fatty layer that surrounds and insulates certain nerve fibers. It acts as an electrical insulator, speeding up the transmission of nerve impulses along the axon. This insulation helps to prevent signal loss or interference, allowing for faster and more efficient communication between neurons. The other options, B: Dura mater, C: Pia mater, and D: Arachnoid mater, are all layers of the meninges that protect the brain and spinal cord, but they do not play a role in insulating nerve fibers for signal transmission like the myelin sheath does.

2. Two objects with different masses collide. What happens to their momentum after the collision?

A. Increases for both objects
B. Decreases for both objects
C. Remains the same for both objects
D. Can increase for one and decrease for the other

Correct answer: C

Rationale: In an isolated system (no external forces), the total momentum

3. Which organ produces insulin?

A. Pancreas
B. Liver
C. Stomach
D. Kidneys

Correct answer: A

Rationale: Rationale: Insulin is a hormone that regulates blood sugar levels by facilitating the uptake of glucose into cells for energy production or storage. The pancreas is an organ located behind the stomach that plays a crucial role in producing insulin. Specialized cells within the pancreas, called beta cells, are responsible for synthesizing and secreting insulin in response to changes in blood glucose levels. Therefore, the pancreas is the organ that produces insulin.

4. Ectopic pregnancy is a serious condition that occurs when a fertilized egg implants outside the uterus. What is the most common location for an ectopic pregnancy?

A. Ovary
B. Fallopian tube
C. Cervix
D. Vagina

Correct answer: B

Rationale: The correct answer is B: Fallopian tube. The fallopian tube is the most common location for an ectopic pregnancy to occur. This is because the fertilized egg typically gets stuck or implants in the fallopian tube instead of traveling to the uterus for normal implantation. If left untreated, an ectopic pregnancy in the fallopian tube can lead to serious complications such as tubal rupture and internal bleeding. The other options (ovary, cervix, vagina) are not typical sites for implantation of a fertilized egg and are less likely to result in an ectopic pregnancy.

5. Bone is a type of

A. Epithelial tissue
B. Connective tissue
C. Hard connective tissue
D. Muscle tissue

Correct answer: C

Rationale: The correct answer is C: "Hard connective tissue." Bone is classified as hard connective tissue because it is composed of cells embedded in a matrix of mineralized collagen fibers, providing support and protection to the body. Epithelial tissue (A) covers body surfaces and lines cavities, while connective tissue (B) includes bone, cartilage, and blood. Muscle tissue (D) is responsible for movement and is not the same as bone tissue.

6. The bones of the skull are classified as what type of bone?

A. Long bone
B. Short bone
C. Flat bone
D. Irregular bone

Correct answer: C

Rationale: The correct answer is C: Flat bone. The bones of the skull are classified as flat bones due to their thin, flattened shape. Flat bones provide protection to vital organs and have a broad surface for muscle attachment. Long bones, like the femur, are characterized by their elongated shape, while short bones, such as those in the wrist and ankle, are cube-shaped. Irregular bones have complex shapes and do not fit into the other bone categories. In this case, the flat bones of the skull best fit the classification.