MCAT Biology : Bone
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Example Questions
Example Question #341 : Mcat Biological Sciences
Rickets is a disorder that is commonly caused by a vitamin D deficiency. The disorder results in bones that can bend and cause deformities.
Based on this information, what is the effect of rickets on the bones of a patient?
There is a decrease of collagen in the bones
There is a decrease of calcium in the bones
There are not enough osteoblasts in order to create bone matrix
There is too much calcium deposited in the bones
There is a decrease of calcium in the bones
Vitamin D aids in calcium absorption in the small intestine. In the absence of vitamin D, inadequate absorption causes a deficiency of calcium in the body. Without calcium, the bones will not have adequate tensile strength, which can cause a bowing effect in bones that support weight, such as the femurs. Collagen in the bones is associated with resistance to compression, rather than tensile strength, and is not linked to vitamin D.
Example Question #1 : Other Bone Concepts
The patella is attached to the tibia by a thick band of fibrous tissue referred to as a __________.
joint
ligament
muscle
tendon
ligament
Ligaments connect a bone to another bone, while tendons attach a muscle to a bone. Since two bones are being connected by the fibrous band of tissue in question, we can confirm that it is a ligament.
Muscle does not actually form a functional connection; rather, muscle will transition to a tendon, which will connect to a bone. Joints are comprised of several different structures and tissues, and are the articulations between two bones.
Example Question #33 : Bone
Several ligaments act together to join the femur and tibia, forming the knee joint. The complexity of the knee makes it prone to injury. A direct blow to the anterior upper tibia can damage the posterior cruciate ligament, while a blow to the posterior upper tibia can damage the anterior cruciate ligament. The collateral ligaments are located medial and lateral to the joint, and can be damaged from blunt trauma to the sides of the knee.
A skier falls, twists his right knee, and experiences excruciating pain at the inner side of the knee. Upon consulting a physician, the skier learns that he has torn one of the ligaments in his knee. The location of pain and cause of injury are most consistent with what kind of ligament tear?
Lateral collateral ligament (LCL)
Anterior cruciate ligament (ACL)
Posterior cruciate ligament (PCL)
Medial collateral ligament (MCL)
Medial collateral ligament (MCL)
Skiers and American football players are prone to medial collateral ligament (MCL) injuries. The MCL is a major ligament of the knee that resides on the inner (medial) side of the knee. The MCL is connected to the tibia and femur, as well as the meniscus and anterior cruciate ligament, making compound injuries common.
The anterior cruciate ligament resides at the front (anterior) side of the knee, while the posterior cruciate ligament resides to the back (posterior) of the knee. The medial meniscus is a fibrocollagen band that is fused with the MCL.
Example Question #311 : Systems Biology And Tissue Types
Which of the follwoing is not an important function of bone?
Organ and nerve protection
Muscular contraction
Regulation of ion concentration
Regulation of pH through hydration
Regulation of pH through hydration
The skeleton plays a role in musclular contraction in that it serves as an anchor and provides leverage against which muscles can exert force. It also serves as protection and support for soft tissues. Bones also maintain certain ion concentrations. The correct answer choice is the regulation of pH through hydration, which is not a function of the skeletal system.
Example Question #312 : Systems Biology And Tissue Types
Bone hardness is primarily due to which of the following?
Hydroxyapatite (composed of calcium and phosphorus) and collagen
Hydroxyapatite (composed of calcium and bicarbonate) and collagen
Hydroxyapatite (composed of glycosaminoglycans and collagen) and bicarbonate
Glycosaminoglycans and collagen
Hydroxyapatite (composed of calcium and phosphorus) and collagen
There are organic (collagen) and inorganic (hydroxyapatite) components of the bone that contribute to its characteristic hardness. The key here is knowing the composition of hydroxypatite, which is primarily constructed of calcium and phosphorus.
Example Question #34 : Bone
Which of the following would cause a bone to lose flexibility?
Removal of proteins
Removal of hydroxyapatite
Removal of bone minerals
Removal of organic and inorganic bone components
Removal of proteins
Collagen is a protein that allows the bone to be somewhat flexible, so "removal of proteins" is the only correct answer. Other answer choices involve inorganic bone material, which add to hardness of the skeleton, but not to its flexibility.
Example Question #33 : Bone
Haversian systems are found in which of the following?
Compact bone
Red bone marrow
Spongy bone
Yellow bone marrow
Compact bone
Compact and spongy bone have similar chemical and structural compositions and are both hard and resistant to compression; however, due to the fact that compact bone is denser, nutrients are delievered through canals called Haversian systems in compact bone; spongy bone is less dense and lacks these specialized canals.
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