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The diencephalon

The diencephalon is the one region of the adult brain that retains its name from embryologic development. The etymology of the word diencephalon translates to “through brain.” It is the connection between the cerebrum and the rest of the nervous system, with one exception. The rest of the brain, the spinal cord, and the PNS all send information to the cerebrum through the diencephalon. Output from the cerebrum passes through the diencephalon. The single exception is the system associated with olfaction    , or the sense of smell, which connects directly with the cerebrum. In the earliest vertebrate species, the cerebrum was not much more than olfactory bulbs that received peripheral information about the chemical environment (to call it smell in these organisms is imprecise because they lived in the ocean).

The diencephalon is deep beneath the cerebrum and constitutes the walls of the third ventricle. The diencephalon can be described as any region of the brain with “thalamus” in its name. The two major regions of the diencephalon are the thalamus itself and the hypothalamus ( [link] ). There are other structures, such as the epithalamus    , which contains the pineal gland, or the subthalamus    , which includes the subthalamic nucleus that is part of the basal nuclei.

Thalamus

The thalamus    is a collection of nuclei that relay information between the cerebral cortex and the periphery, spinal cord, or brain stem. All sensory information, except for the sense of smell, passes through the thalamus before processing by the cortex. Axons from the peripheral sensory organs, or intermediate nuclei, synapse in the thalamus, and thalamic neurons project directly to the cerebrum. It is a requisite synapse in any sensory pathway, except for olfaction. The thalamus does not just pass the information on, it also processes that information. For example, the portion of the thalamus that receives visual information will influence what visual stimuli are important, or what receives attention.

The cerebrum also sends information down to the thalamus, which usually communicates motor commands. This involves interactions with the cerebellum and other nuclei in the brain stem. The cerebrum interacts with the basal nuclei, which involves connections with the thalamus. The primary output of the basal nuclei is to the thalamus, which relays that output to the cerebral cortex. The cortex also sends information to the thalamus that will then influence the effects of the basal nuclei.

Hypothalamus

Inferior and slightly anterior to the thalamus is the hypothalamus    , the other major region of the diencephalon. The hypothalamus is a collection of nuclei that are largely involved in regulating homeostasis. The hypothalamus is the executive region in charge of the autonomic nervous system and the endocrine system through its regulation of the anterior pituitary gland. Other parts of the hypothalamus are involved in memory and emotion as part of the limbic system.

The diencephalon

This figure shows the location of the thalamus, hypothalamus and pituitary gland in the brain.
The diencephalon is composed primarily of the thalamus and hypothalamus, which together define the walls of the third ventricle. The thalami are two elongated, ovoid structures on either side of the midline that make contact in the middle. The hypothalamus is inferior and anterior to the thalamus, culminating in a sharp angle to which the pituitary gland is attached.

Questions & Answers

how many litres of blood does a human body have
George Reply
hi
Sweetlin
hliii
Mohd
there are around 10.5p.(5literes) adult body
Shubu
what is homeostasis
Antwi Reply
it is self regulating ability of the body to adjust to the surroundings
Angela
it is like maintaining an equilibrium type of environment between the inside and outside of the body, so that our body can adjust to the external environmental changes
Angela
this is the negative feedback loop of the body,.... that naturally helps to keep the body in a stable or constant internal environment.
Matthew
this is the activities in the body that keeps the internal environment of the body in equilibrium or to keep it constant.
Ikenze
list four long bones
Mary Reply
the four long bones are: tibia, fibula, femur, and humerus.
Isaac
from Zambia
Mary
femur, radius , ulnar, humerus
Om
humerus, femur, tibia and fibula
Sheryl
Humerus,redius,ulnar,in hand. Femur,tibia,fibula in leg. it is long bone.
Sneha
there is contradiction between radius ulna & tibia fibula because of the variation in the upper and lower limb of the according to growth and development of human body so humerus & femur are longer bones ( ex you can see Michael phaleps upper limb is longer than the lower limb)
Prashant
if anyone having dout so he she can please explain it to me
Prashant
which one want explain something
Dr
sir post which I have send look at it & tell is it correct or not
Prashant
about four long bones is the topic
Prashant
femur, humerus, tibia and fibula
Ikenze
how are you doing
Rekah Reply
hi everyone.
AR
Im new here, I came from the philippines. I study nursing. Im a first year student.
AR
really
Isaac
so what help do you want
Isaac
yeah I came from the philippines..and I have struggle about this subject the anatomy and physiology because I dont any books that I barrowed with. I cant afford buy books.
AR
hii
Meher
I'm from India
Jamy
I struggle with this subject
Jamy
can I ask here a question I hope you can help me because I dont have any references/books that I should see or read it.
AR
AR
Meher
you are from india nice to talk to you jamy.
AR
Alright Always drop your concerns here and they will be addressed. Thanks sister.
Isaac
nice meeting with you
Jamy
I am also from India
shiv
thank you Isaac.
AR
yes Meher?
AR
you are all india
AR
By the way I have question
AR
describe a person in anatomical position?
AR
i come from Ghana
Isaac
are you all nursing students?
AR
no I'm pharmacy student
Jamy
oh nice.
AR
yes
shiv
jamy me too
Meher
yes
shiv
yes
shiv
my name is sweety
Jamy
you have any chat group that we can talk there.
AR
Anatomical position is the description of any region or part of the body in a specific stance. In the anatomical position, the body is upright, directly facing the observer, feet flat and directed forward. The upper limbs are at the body's sides with the palms facing forward. The standard anatomic
Isaac
yes
shiv
jamy is my nick name
Jamy
I am a nursing student
Isaac
thank you Isaac
AR
Final year, level 400
Isaac
ohh what year are you now?
AR
Nice
AR
welcome madam
Isaac
do you have any chat group here
AR
describe the six levels of organization of the body and describe the major characteristics of each level?
AR
ahh its okay jammy
AR
jammy i am from kashmir nd u
Meher
It is convenient to consider the structures of the body in terms of fundamental levels of organization that increase in complexity, such as (from smallest to largest): chemicals, cells, tissues, organs, organ systems, and an organism.
Isaac
hi
Yaminah
am from somalia
Yaminah
5th year in medical student nice to meet ya all
Yaminah
thxs yaminah
Meher
y not.. jamy for what purpose...?
Meher
inbox me i will guide u ...?
Meher
i also dont know...?
Meher
open this app - click 'start learning' - click 'preface' - select the chat that you wanna join into I guess that is it !
Angela
Hello am from Sierra Leone
junisa
I am from Kerala
Angela
I am from india
Om
I am from Tripura
FAKE
tell the easyst way to learn anatomy
Khaliif Reply
try to draw 👌
Rahil
what
shiv
learn subject with drawing anatomy diagrams some with flow chart i dont say it is easiest way bt yes u can rember for longer period
Shakerah
ooh
shiv
Can u say me parturation
Sweetlin
parturition is one of the 7 stages of human reproduction. parturition is actually that last or the 7th stage, that is giving birth to the baby or the delivery of the baby.
Angela
Mr. khaliff.. never ever use a short cut or easiest way to Acquire knowledge.. the knowledge what we got from an easiest way , cuz it will be become temporary, not permanent.. especially in the anatomy.. cuz it's a complex subject.. you can shortlist as per your syllabus, not yourself..
Sanjith
I think shakeerah's ideology of learning anatomy is one of a best method to easy learning.. and try to share with your friends or here, what you've acknowledged each day.. thankyu
Sanjith
I am agree with that point
shiv
if u get time aftr learning this 2_3 ppl join , make group make questions if urself even if its silly make it as flash card sometimes u fail , its okay. dont be less heart. u vl do it anyway if u concentrate. bt choosing ppl or the selection of ppl during studying it really matters.
Shakerah
if u get time aftr learning this 2_3 ppl join , make group make questions if urself even if its silly make it as flash card sometimes u fail , its okay. u vl do it anyway if u concentrate. bt choosing ppl or the selection of ppl during studying it really matters.
Shakerah
😊
Sanjith
what Tk
shiv
good night all... stay safe.. bye
Sanjith
hello im new here, im a nursing student
SHUGA Reply
ooh
shiv
welcome
shiv
wlcm
Rahil
dub
Ndowmi
maleria
Ndowmi
Anopheles
shiv
welcome shuga
Om
please am new here. Am a nurse awaiting to be posted .
Ntiamoah
hi I'm new here too
faleke
Feleke Sharon Welcome
FAKE
FAKE DrLUPO thank you
faleke
hello guys
Chuks
hello guys 🤗
Sneha
hello
Chuks
whose in Nigeria
Chuks
🙋🙋
faleke
what is inner breeding
Vijay Reply
you don't have any answer
Vijay
please don't waste my time
Vijay
wait
shiv
inbreeding is mating or breeding with organism that are genetically related
shiv
s
Pankaj
who this SRY
Pankaj
inner breeding is breeding among the same species of organisms
Anna
*inbreeding
Anna
yes same speciesor same genetic organism
shiv
description of the menstruation cycle
Namyalo Reply
explain the menstruation cycle
Namyalo
explain the menstrual cycle
Ugo
menstrual cycle is came due to FSH and LH
shiv
fsh
Ndowmi
This is the periodic release of waste(blood) from the reproductive organ of the females (human) for a period of some days, after which or during then, ovulation takes place, which is the release of eggs from the ovaries for fertilization by the spermatozoa.
Ikenze
Description of menestraul cycle
Amos Reply
what is the anatomy
FAKE Reply
Anatomy is study of structure of organs.
Sneha
thanks
FAKE
The scientific study of the structure of human or animal bodies.
FAKE
I was confused as to which one would be right and I asked
FAKE
My answer and you answer both are right.
Sneha
The scientific study of the human and animal internal and external structure of the body.
Ikenze
i want to improve my study i like this app i interest physiology and anatomy
Su Reply
I also like this app am really interested in learning anatomy and physiology.
Johny
I have this book with my anatomy class it's awesome! also if look at crashcourse anatomy on you tube!
AMY
what the name
isaiah
umesh. rede
Rede
what is heart and long type answer
Lalita Reply
its a organ in the body
ay
describe about hear chambers.. valves.. arteries.. veins.. circulation.. inferior/superior venacava, aorta., tricuspid valve, mitral valve. pulmonary artery/vein, how oxigenation occur,systolic presure diastolic pressure.. stroke volume,cardiac output, ets.. heart located in which place, describe it
Sanjith
if you describe what I cited up, thogh you can write a long type answer about heart
Sanjith
hi
Riyaz
autonomic functions took over
Vanarith Reply
What did they take over?
Eric
what is the average volume of blood in men and why does it varrie from women?
Esther Reply
what is the average volume of blood in men
Esther
5to6liter
Sarita
5to6liter dt
Sarita
umesh. rede
Rede
estimated at 5.5litres
Ikenze
what is the definition of anatomy
Noriah Reply
Search google
killer
^of
chieng
The study of the structure or internal workings of something. "Machiavelli's anatomy 
Eric

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Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
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