Anatomy Practice Quiz 6

The iliacus muscle does not meet at the perineal body. The perineal body is a fibrous structure located between the anus and the vagina in females or the anus and the scrotum in males. It serves as a point of attachment for various muscles involved in the pelvic floor. The superficial transverse perineal, external anal sphincter, bulbospongiosus, and deep transverse perineal muscles all meet at the perineal body. However, the iliacus muscle is not part of the pelvic floor and does not have any direct attachment to the perineal body.

The plantaris muscle is absent in 5-10% of people. This muscle is a small, thin muscle that runs along the back of the lower leg. While it is not essential for normal movement or function, it can sometimes be used as a graft for surgical procedures. Its absence is a normal anatomical variation and does not typically cause any significant issues or impairments.

The cuboid articulates with the 5th metatarsal. This means that the cuboid bone forms a joint with the 5th metatarsal bone, allowing for movement and stability in the foot.

The Bartholin glands are partially surrounded by the bulbospongiosus muscles. These glands are located on either side of the vaginal opening and their main function is to secrete fluid that lubricates the vagina during sexual arousal. The bulbospongiosus muscles are found in the pelvic floor and they help to support the pelvic organs, including the vagina. Therefore, it makes sense that the Bartholin glands would be partially surrounded by these muscles to provide support and protection.

The sciatic nerve does not enter the pudendal canal at the lesser sciatic notch. The pudendal canal is a passageway in the pelvis that contains the internal pudendal artery, pudendal nerve, nerve to obturator internus, and internal pudendal vein. The sciatic nerve, on the other hand, is a large nerve that runs from the lower back down the back of the leg and does not pass through the pudendal canal.

The quadratus femoris does not attach to the greater trochanter of the femur. It is a muscle located on the posterior side of the hip joint and attaches to the ischial tuberosity, which is a bony prominence on the ischium bone of the pelvis. The other muscles listed in the question (obturator internus, piriformis, superior gemelli, and inferior gemelli) all attach to the greater trochanter of the femur.

The nerves of the sacral plexus are either embedded in or posterior to the piriformis muscle. This muscle is located in the buttocks and plays a role in rotating the hip joint. The positioning of the nerves in relation to the piriformis muscle is important as it can impact their function and any compression or impingement of the nerves can lead to symptoms such as pain, numbness, or weakness in the lower body.

The statement that the iliolumbar artery branches from the anterior division of the internal iliac artery superior to the internal pudendal artery is false. The iliolumbar artery actually branches from the posterior division of the internal iliac artery, not the anterior division.

The pes anserinus is a tendon located on the inner side of the knee joint. It is formed by the tendons of the sartorius, gracilis, and semitendinosus muscles. These tendons attach to the tibia bone. The semimembranosus muscle, on the other hand, attaches to the ischial tuberosity of the pelvis and does not contribute to the formation of the pes anserinus. Therefore, the semimembranosus muscle does not have an attachment at the pes anserinus.

The gastrocnemius muscle forms the inferolateral and medial border of the popliteal fossa. The popliteal fossa is a diamond-shaped space located at the back of the knee joint. The gastrocnemius muscle is one of the major muscles of the calf and it originates from the femur and inserts into the Achilles tendon. Its position and size contribute to the formation of the boundaries of the popliteal fossa.

The pubococcygeus muscle is not innervated by the perineal branch of the pudendal nerve. The perineal branch of the pudendal nerve primarily innervates the muscles of the perineum, which include the bulbospongiosus, deep transverse perineal, superficial transverse perineal, and ischiocavernosus muscles. The pubococcygeus muscle, on the other hand, is innervated by the levator ani nerve, which is a branch of the pudendal nerve.

The greater sciatic notch is a bony structure located on the pelvis. It is wider in females compared to males, allowing more space for the passage of nerves and blood vessels during childbirth. This anatomical difference is present in females but not in males.

The obturator nerve does not supply pelvic structures. It is a nerve that originates from the lumbar plexus and primarily innervates the muscles of the medial thigh. It does not have any direct innervation to the pelvic organs or structures.

The correct answer is A and B. The medial thigh muscles are mostly innervated by the obturator nerve and serve to adduct the thigh. Gracilis, semitendinosus, and vastus medialis are examples of medial thigh muscles.

The correct answer is the medial surface. The medial surface of the tibia is the inner side or the side that faces the midline of the body. It connects both the anterior and interosseous borders of the tibia, which are located on the front and in between the tibia and fibula bones respectively. This connection helps to provide stability and support to the tibia bone.

The bulbospongiosus muscle compresses the deep dorsal vein of the penis during erection, impeding drainage. This muscle surrounds the bulb of the penis and contracts during ejaculation, helping to expel semen. By compressing the deep dorsal vein, it prevents blood from leaving the penis too quickly, allowing for a sustained erection.

The sciatic nerve does not directly innervate the semitendinosus, gracilis, adductor magnus, or gastrocnemius muscles. Therefore, the correct answer is "nothing."

The obturator externus muscle is not in the anterior compartment of the thigh. The anterior compartment of the thigh consists of the iliopsoas, quadriceps femoris, sartorius, and pectineus muscles. The obturator externus muscle is located in the medial compartment of the thigh.

The obturator internus muscle passes through the lesser sciatic foramen and attaches to the greater trochanter of the femur.

The corpus cavernosum is a pair of erectile tissues that make up the main part of the penis, responsible for the majority of its rigidity during an erection. The crura, bulb, ischiocavernosus muscle, and bulbospongiosus muscle are all structures that are part of the root of the penis. Therefore, the corpus cavernosum does not comprise the root of the penis.

During ejaculation, the sympathetic nervous system is responsible for the closure of the internal urethral sphincter. This sphincter prevents the backflow of semen into the bladder by closing off the opening of the bladder. This action allows the semen to be expelled through the urethra and out of the body. The contraction of the urethral muscle, contraction of the bulbospongiosus muscle, and constriction of the helicine arteries are all parasympathetic events that occur during ejaculation.

The fovea is a medially placed depression in the head of the femur. This is true because the fovea is a small pit-like structure located on the medial surface of the femoral head. It serves as the attachment site for the ligament of the head of the femur, which helps to stabilize the hip joint. The other statements are incorrect because the angle of inclination of the femur decreases with maturation, the intertrochanteric crest joins the greater and lesser trochanters posteriorly, the epicondyles of the femur articulate with the condyles of the femur, and the intercondylar fossa is located posteriorly and inferiorly.

The lateral circumflex femoral artery gives rise to the superior lateral genicular artery.

The correct answer is that the superior boundary is the apex of the triangle. In anatomy, the superior boundary of the femoral triangle is formed by the inguinal ligament, not the apex. The apex of the triangle is formed by the meeting point of the sartorius muscle and the adductor longus muscle. The femoral triangle is a region in the upper thigh that contains important structures such as the femoral nerve, femoral artery, and femoral vein.

The rectal ampulla does not widen at the anorectal junction. The rectal ampulla is the expanded portion of the rectum just above the anal canal, and it maintains a relatively constant diameter throughout. The widening of the rectum actually occurs at the rectosigmoid junction, where the rectum transitions into the sigmoid colon.

The function of the medial compartment of the femoral sheath is to allow expansion of the femoral vein during Valsalva strain. This is important because during Valsalva strain, there is increased pressure in the abdominal cavity, which can compress the femoral vein. The expansion of the femoral vein in the medial compartment of the femoral sheath helps to accommodate this increased pressure and prevent compression of the vein.

Pes anserinus is a structure located on the anteromedial surface of the proximal part of the tibia. The muscles that join at pes anserinus (sartorius, gracilis, and semitendinosus) are each innervated by a different nerve. However, biceps femoris is not directly related to pes anserinus. Pes anserinus does not provide a direct surgical route to repair the lateral collateral ligament.

The short head of the biceps femoris is innervated by the fibular nerve. The fibular nerve is a branch of the sciatic nerve, which is the largest nerve in the body. It supplies motor innervation to the muscles of the posterior compartment of the leg, including the short head of the biceps femoris. The tibial nerve, another branch of the sciatic nerve, innervates the other muscles of the posterior compartment of the leg. The femoral nerve, on the other hand, innervates the muscles of the anterior compartment of the thigh.

The flexor hallucis longus muscle supports the medial longitudinal arches of the foot. This muscle is located in the lower leg and it helps in flexing the big toe. By providing support to the arches of the foot, the flexor hallucis longus muscle contributes to maintaining the stability and structure of the foot during activities such as walking and running.

The greater vestibular glands are located in the superficial perineal pouch. These glands are also known as Bartholin's glands and are found on either side of the vaginal opening. They secrete mucus to lubricate the vestibule and aid in sexual intercourse. The other options listed are not located in the superficial perineal pouch.

The intermediate urethra is the correct answer because it begins at the apex of the prostate and traverses the deep perineal pouch. The prostatic urethra is incorrect because it is located within the prostate gland. The intramural urethra is incorrect because it refers to the portion of the urethra that passes through the wall of the bladder. The spongy urethra is incorrect because it refers to the portion of the urethra that runs through the penis. The corpus spongiosum is incorrect because it is a mass of erectile tissue that surrounds the spongy urethra.

The answer is true because the arcuate popliteal ligament is indeed located on the lateral side of the knee joint, while the oblique popliteal ligament is located on the medial side. This arrangement helps to provide stability to the knee joint by preventing excessive rotation and hyperextension.

The statement that is false concerning the superficial muscles of the gluteal region is that one of their functions is to laterally rotate the thigh. The superficial muscles of the gluteal region, including the gluteus maximus, medius, and minimus, have various functions such as extension, abduction, and stabilization of the hip joint. However, they are not primarily responsible for lateral rotation of the thigh. This function is mainly carried out by the deep muscles of the hip joint, such as the piriformis and obturator externus.

The correct answer is that the medial and lateral circumflex femoral arteries arise from the anterior aspect of the femoral artery. This statement is false because the medial and lateral circumflex femoral arteries actually arise from the deep femoral artery, not the anterior aspect of the femoral artery.

The piriformis muscle is not a part of the triceps coxae group. The triceps coxae group consists of three muscles: the obturator internus, the superior gemelli, and the quadratus femoris. The piriformis muscle is located in the gluteal region and is responsible for rotating the hip joint. While it is in close proximity to the triceps coxae group, it is not considered a part of this specific group of muscles.