USMLE Step1 STEP1 Dumps in PDF

Free USMLE STEP1 Real Questions (page: 22)

A 45-year-old female patient develops Parinauds syndrome (vertical gaze palsy) and an MRI shows a large tumor of her pineal gland. The tumor is not only compressing her tectum, causing the vertical gaze palsy, but also obstructing the underlying cerebrospinal fluid pathway causing progressive noncommunicating hydrocephalus. The obstruction causes immediate accumulation of cerebrospinal fluid in which of the following?

  1. cerebral aqueduct of Sylvius
  2. fourth ventricle
  3. lateral ventricle
  4. subarachnoid space
  5. third ventricle

Answer(s): E

Explanation:

In this situation, the cerebrospinal fluid will accumulate immediately in the third ventricle and cause hydrocephalus. The flow of cerebrospinal fluid is normally from the lateral ventricles (choice C) to the third ventricle and then by way of the cerebral aqueduct of Sylvius (choice A) to the fourth ventricle (choice B).
From there the cerebrospinal fluid flows out of the brain into the subarachnoid space (choice D). A blockage of the cerebral aqueduct will result in immediate accumulation of cerebrospinal fluid in the third ventricle. Because the cerebrospinal fluid no longer flows from the ventricular system to the subarachnoid space, the resulting hydrocephalus is termed noncommunicating.



Apatient has been severely injured in the back of the head during a mugging attempt and imaging studies reveal possible fracture of the skull along with the C1 (atlas) vertebra. The patient is also hemorrhaging from the vertebral artery in this location, and the attending surgeon will attempt to stop the bleeding by access through the suboccipital triangle. Which of the following muscles attaches from the transverse process of C1 to the occipital bone and forms the lateral border of the suboccipital triangle?

  1. obliquus capitis inferior
  2. obliquus capitis superior
  3. rectus capitis posterior major
  4. rectus capitis posterior minor
  5. semispinalis cervicis

Answer(s): B

Explanation:

The obliquus capitis superior, attached between the transverse process of C1 and the suboccipital bone between the nuchal lines. It forms the lateral border of the suboccipital triangle. The obliquus capitis inferior (choice A) is the inferior border of the triangle, attaching from the spinous process of C2 to the transverse process of C1. The rectus capitis posterior major (choice C) inserts from the spinous process of C2 into the inferior nuchal line on the occipital bone; it forms the medial border of the suboccipital triangle. The rectus capitis posterior minor (choice D) lies medial to the rectus capitis posterior major. The semispinalis cervicis (choice E) does not participate in the formation of the suboccipital triangle.



Your patient presents in your office complaining of hoarseness. During your examination, you find that one vocal fold has deviated toward the midline and does not abduct during deep inspiration or vocalization. You also observe that touch sensation in the vestibule of the larynx appears to be intact. Which laryngeal muscle is most important in abduction of the vocal folds?

  1. cricothyroid
  2. lateral cricoarytenoid
  3. posterior cricoarytenoid
  4. thyroarytenoid
  5. transverse arytenoid

Answer(s): C

Explanation:

The vocal folds are abducted and the rima glottidis is widened by the posterior cricoarytenoid muscles that rotate the arytenoid cartilages laterally. The cricothyroid muscles (choice A) tense and lengthen the vocal ligament by tilting the thyroid cartilage forward. The lateral cricoarytenoid muscles (choice B) adduct the vocal folds by medially rotating the arytenoid cartilages. The thyroarytenoid muscles (choice D) decrease the tension and length of the vocal ligaments by tilting the thyroid cartilages posteriorly. The transverse arytenoids muscle (choice E) adducts the vocal folds by pulling the arytenoid cartilages together.



Your patient presents in your office complaining of hoarseness. During your examination, you find that one vocal fold has deviated toward the midline and does not abduct during deep inspiration or vocalization. You also observe that touch sensation in the vestibule of the larynx appears to be intact.
You suspect that a nerve has been damaged, but which nerve is most likely involved?

  1. external laryngeal
  2. glossopharyngeal
  3. inferior laryngeal
  4. internal laryngeal
  5. superior laryngeal

Answer(s): C

Explanation:

The inferior laryngeal nerve is motor to the intrinsic muscles of the larynx except the cricothyroid muscle, and is sensory to the larynx below the level of the vocal fold. The external laryngeal nerve (choice A) is the branch of the superior laryngeal nerve that contains the motor fibers to the cricothyroid muscle and to the cricopharyngeus muscle. The glossopharyngeal nerve (choice B) does not supply either motor or sensory fibers to the larynx. The internal laryngeal nerve (choice D) is the branch of the superior laryngeal nerve that contains the sensory fibers to the laryngeal mucosa above the vocal fold. The superior laryngeal nerve (choice E) is sensory to the laryngeal mucosa above the vocal fold and also includes motor fibers to the cricothyroid muscle.



During maturation of the oocytes, which of the following structures retain almost all of the cytoplasm after the first meiotic division?

  1. first polar body
  2. ovum
  3. primary oocyte
  4. second polar body
  5. zygote

Answer(s): B

Explanation:

The first meiotic division results in two secondary oocytes: the ovum retains almost all of the cytoplasm whereas the first polar body (choice A) does not. Primary oocytes (choice C) are the cells undergoing the first meiotic division. The second polar body (choice D) is formed after the second meiotic division. The zygote (choice E) is the fertilized ovum.



Share your comments for USMLE STEP1 exam with other users:

A
Ajay
10/3/2023 12:17:00 PM

could you please re-upload this exam? thanks a lot!

H
him
9/30/2023 2:38:00 AM

great about shared quiz

S
San
11/14/2023 12:46:00 AM

goood helping

W
Wang
6/9/2022 10:05:00 PM

pay attention to questions. they are very tricky. i waould say about 80 to 85% of the questions are in this exam dump.

M
Mary
5/16/2023 4:50:00 AM

wish you would allow more free questions

T
thomas
9/12/2023 4:28:00 AM

great simulation

S
Sandhya
12/9/2023 12:57:00 AM

very g inood

A
Agathenta
12/16/2023 1:36:00 PM

q35 should be a

M
MD. SAIFUL ISLAM
6/22/2023 5:21:00 AM

sap c_ts450_2021

S
Satya
7/24/2023 3:18:00 AM

nice questions

S
sk
5/13/2023 2:10:00 AM

ecellent materil for unserstanding

G
Gerard
6/29/2023 11:14:00 AM

good so far

L
Limbo
10/9/2023 3:08:00 AM

this is way too informative

T
Tejasree
8/26/2023 1:46:00 AM

very helpfull

Y
Yolostar Again
10/12/2023 3:02:00 PM

q.189 - answers are incorrect.

S
Shikha Bakra
9/10/2023 5:16:00 PM

awesome job in getting these questions

K
Kevin
10/20/2023 2:01:00 AM

i cant find aws certified practitioner clf-c01 exam in aws website but i found aws certified practitioner clf-c02 exam. can everyone please verify the difference between the two clf-c01 and clf-c02? thank you

D
D Mario
6/19/2023 10:38:00 PM

grazie mille. i got a satisfactory mark in my exam test today because of this exam dumps. sorry for my english.

B
Bharat Kumar Saraf
10/31/2023 4:36:00 AM

some of the answers are incorrect. need to be reviewed.

J
JP
7/13/2023 12:21:00 PM

so far so good

K
Kiky V
8/8/2023 6:32:00 PM

i am really liking it

T
trying
7/28/2023 12:37:00 PM

thanks good stuff

E
exampei
10/4/2023 2:40:00 PM

need dump c_tadm_23

E
Eman Sawalha
6/10/2023 6:18:00 AM

next time i will write a full review

J
johnpaul
11/15/2023 7:55:00 AM

first time using this site

O
omiornil@gmail.com
7/25/2023 9:36:00 AM

please sent me oracle 1z0-1105-22 pdf

J
John
8/29/2023 8:59:00 PM

very helpful

K
Kvana
9/28/2023 12:08:00 PM

good info about oml

C
Checo Lee
7/3/2023 5:45:00 PM

very useful to practice

D
dixitdnoh@gmail.com
8/27/2023 2:58:00 PM

this website is very helpful.

S
Sanjay
8/14/2023 8:07:00 AM

good content

B
Blessious Phiri
8/12/2023 2:19:00 PM

so challenging

P
PAYAL
10/17/2023 7:14:00 AM

17 should be d ,for morequery its scale out

K
Karthik
10/12/2023 10:51:00 AM

nice question

AI Tutor 👋 I’m here to help!