USMLE Step1 STEP1 Dumps in PDF

Free USMLE STEP1 Real Questions (page: 46)

An adult male becomes hypotensive during surgery because of blood loss. Intravenous administration of 500 ml of which of the following solutions will have the greatest effect in restoring blood volume, and thus blood pressure to normal?

  1. blood plasma
  2. distilled water
  3. hypoosmotic NaCl
  4. isotonic dextrose solution
  5. isotonic saline solution

Answer(s): A

Explanation:

Intravenous solutions are distributed in the various body fluid compartments based on osmolality and their ability to penetrate the vascular wall and the cell membrane. The proteins in blood plasma will remain within the vascular compartment because of their low permeability across the vessel wall. Thus, 500 mL of blood plasma will remain in the vascular compartment. Water (choice B) passes across the cell membrane and the vascular wall easily. Hence distilled water will distribute itself between cellular and extracellular spaces, meaning only a small portion will actually contribute to blood volume, the other choices (C, D, and E) cross the vascular barrier and distribute partially to the extravascular space and thus are less effective intravascular volume expanders.



Using laboratory micropuncture technique, blood plasma is collected from both the afferent arteriole and efferent arteriole of a renal cortical glomerulus. Which of the following has the lowest afferent/efferent arteriole concentration ratio?

  1. albumin
  2. chloride
  3. glucose
  4. potassium
  5. sodium

Answer(s): A

Explanation:

The process of glomerular ultrafiltration creates a tubular fluid that is essentially protein free. Hence, as plasma passes from the afferent arteriole, through the glomerular capillaries to the efferent arteriole, the protein albumin concentration rises as approximately 20% of the fluid is filtered out, leaving the albumin behind, giving an afferent/efferent arteriole concentration ratio of approximately 0.8. By contrast, the glomerular capillary membrane is freely permeable to water and other small particles such as glucose (choice A), chloride (choice B), potassium (choice D), and sodium (choice E), so their concentrations do not change as approximately 20% of water and solute are filtered into Bowman's capsule, giving afferent/ efferent arteriole concentration ratios of 1.0.



It is known that stretch receptors contained in the walls of the atria convey nerve impulses to the brainstem via the vagus nerve. Under normal conditions, these nerve impulses are most likely to occur during ventricular systole. What information is communicated to the brain by these nerve impulses?

  1. arterial muscle contraction
  2. diastolic arterial pressure
  3. filling of the atrium by venous pressure
  4. filling of the ventricle
  5. systolic arterial pressure

Answer(s): C

Explanation:

The atrial stretch receptors are depolarized by stretch of the atria proportional to the magnitude of venous- filling pressure. The frequency of action potentials rises to a maximum at the peak of the atrial "v" wave, which signals maximum atrial filling during ventricular contraction. Although the remaining choices (A, B, D, and E) may be influenced by the filling of the heart by venous pressure, the information conveyed to the brain via the atrial stretch receptors relates directly to the filling pressure of the atria themselves.



High-dose glucocorticoid therapy for treatment of rheumatoid arthritis remains highly controversial. It is widely agreed that it is highly effective in controlling acute rheumatoid inflammation, but it may also result in significant adverse effects. Complications of high-dose glucocorticoid therapy include which of the following?

  1. excessive growth in children and acromegaly in adults
  2. hyperkalemia
  3. hyponatremia
  4. suppression of the hypothalamicpituitary-adrenal axis
  5. volume depletion

Answer(s): D

Explanation:

High-dose exogenous glucocorticoids suppress the adrenal neuroendocrine axis. Patients treated for longer than 2 weeks need to be tapered off glucocorticoids slowly to avoid adrenal insufficiency. Other complications of high-dose glucocorticoids include growth suppression, not excessive growth (choice A) in children and volume overload, not volume depletion (choice E). Hyperkalemia (choice B) and hyponatremia (choice C) are observed in adrenal insufficiency due to loss of mineralocorticoid effects and are not relevant to glucocorticoid therapy.



A 53-year-old healthy male undergoes an exercise stress test, running on a treadmill until a maximum exertion is obtained. Which of the following statements correctly describes effects of autonomic nerve activity on the cardiovascular system in such a healthy subject?

  1. inhibition of parasympathetic nerves decreases total peripheral resistance
  2. inhibition of parasympathetic nerves increases heart rate
  3. inhibition of parasympathetic nerves increases total peripheral resistance
  4. stimulation of parasympathetic nerves decreases the strength of cardiac ventricular contractions
  5. stimulation of sympathetic nerves decreases the strength of cardiac ventricular contractions

Answer(s): B

Explanation:

Since cardiac SA nodal cells receive tonic input from both sympathetic and parasympathetic nerves, heart rate increases whenever sympathetic firing rate increases or parasympathetic firing rate decreases. In humans, the parasympathetic innervation of ventricular muscle is negligible (choice D), and the strength of contraction increases with increasing preload and with increasing sympathetic firing rate (choice E). With few exceptions, blood vessels are not innervated by parasympathetic nerves, and there is little effect of changes in parasympathetic tone on total peripheral resistance (choices A and C).



Share your comments for USMLE STEP1 exam with other users:

C
ciken
8/24/2023 2:55:00 PM

help so much

B
Biswa
11/20/2023 9:28:00 AM

understand sql col.

S
Saint Pierre
10/24/2023 6:21:00 AM

i would give 5 stars to this website as i studied for az-800 exam from here. it has all the relevant material available for preparation. i got 890/1000 on the test.

R
Rose
7/24/2023 2:16:00 PM

this is nice.

A
anon
10/15/2023 12:21:00 PM

q55- the ridac workflow can be modified using flow designer, correct answer is d not a

N
NanoTek3
6/13/2022 10:44:00 PM

by far this is the most accurate exam dumps i have ever purchased. all questions are in the exam. i saw almost 90% of the questions word by word.

E
eriy
11/9/2023 5:12:00 AM

i cleared the az-104 exam by scoring 930/1000 on the exam. it was all possible due to this platform as it provides premium quality service. thank you!

M
Muhammad Rawish Siddiqui
12/8/2023 8:12:00 PM

question # 232: accessibility, privacy, and innovation are not data quality dimensions.

V
Venkat
12/27/2023 9:04:00 AM

looks wrong answer for 443 question, please check and update

V
Varun
10/29/2023 9:11:00 PM

great question

D
Doc
10/29/2023 9:36:00 PM

question: a user wants to start a recruiting posting job posting. what must occur before the posting process can begin? 3 ans: comment- option e is incorrect reason: as part of enablement steps, sap recommends that to be able to post jobs to a job board, a user need to have the correct permission and secondly, be associated with one posting profile at minimum

I
It‘s not A
9/17/2023 5:31:00 PM

answer to question 72 is d [sys_user_role]

I
indira m
8/14/2023 12:15:00 PM

please provide the pdf

R
ribrahim
8/1/2023 6:05:00 AM

hey guys, just to let you all know that i cleared my 312-38 today within 1 hr with 100 questions and passed. thank you so much brain-dumps.net all the questions that ive studied in this dump came out exactly the same word for word "verbatim". you rock brain-dumps.net!!! section name total score gained score network perimeter protection 16 11 incident response 10 8 enterprise virtual, cloud, and wireless network protection 12 8 application and data protection 13 10 network défense management 10 9 endpoint protection 15 12 incident d

A
Andrew
8/23/2023 6:02:00 PM

very helpful

L
latha
9/7/2023 8:14:00 AM

useful questions

I
ibrahim
11/9/2023 7:57:00 AM

page :20 https://exam-dumps.com/snowflake/free-cof-c02-braindumps.html?p=20#collapse_453 q 74: true or false: pipes can be suspended and resumed. true. desc.: pausing or resuming pipes in addition to the pipe owner, a role that has the following minimum permissions can pause or resume the pipe https://docs.snowflake.com/en/user-guide/data-load-snowpipe-intro

F
Franklin Allagoa
7/5/2023 5:16:00 AM

i want hcia exam dumps

S
SSA
12/24/2023 1:18:00 PM

good training

B
BK
8/11/2023 12:23:00 PM

very useful

D
Deepika Narayanan
7/13/2023 11:05:00 PM

yes need this exam dumps

B
Blessious Phiri
8/15/2023 3:31:00 PM

these questions are a great eye opener

J
Jagdesh
9/8/2023 8:17:00 AM

thank you for providing these questions and answers. they helped me pass my exam. you guys are great.

T
TS
7/18/2023 3:32:00 PM

good knowledge

A
Asad Khan
11/1/2023 2:44:00 AM

answer 10 should be a because only a new project will be created & the organization is the same.

R
Raj
9/12/2023 3:49:00 PM

can you please upload the dump again

C
Christian Klein
6/23/2023 1:32:00 PM

is it legit questions from sap certifications ?

A
anonymous
1/12/2024 3:34:00 PM

question 16 should be b (changing the connector settings on the monitor) pc and monitor were powered on. the lights on the pc are on indicating power. the monitor is showing an error text indicating that it is receiving power too. this is a clear sign of having the wrong input selected on the monitor. thus, the "connector setting" needs to be switched from hdmi to display port on the monitor so it receives the signal from the pc, or the other way around (display port to hdmi).

N
NSPK
1/18/2024 10:26:00 AM

q 10. ans is d (in the target org: open deployment settings, click edit next to the source org. select allow inbound changes and save

M
mohamed abdo
9/1/2023 4:59:00 AM

very useful

T
Tom
3/18/2022 8:00:00 PM

i purchased this exam dumps from another website with way more questions but they were all invalid and outdate. this exam dumps was right to the point and all from recent exam. it was a hard pass.

E
Edrick GOP
10/24/2023 6:00:00 AM

it was a good experience and i got 90% in the 200-901 exam.

A
anonymous
8/10/2023 2:28:00 AM

hi please upload this

B
Bakir
7/6/2023 7:24:00 AM

please upload it

AI Tutor 👋 I’m here to help!