<< Chapter < Page Chapter >> Page >

Chordae tendineae and papillary muscles

This photo shows the inside of the heart with the main muscles labeled.
In this frontal section, you can see papillary muscles attached to the tricuspid valve on the right as well as the mitral valve on the left via chordae tendineae. (credit: modification of work by “PV KS”/flickr.com)

The walls of the ventricle are lined with trabeculae carneae    , ridges of cardiac muscle covered by endocardium. In addition to these muscular ridges, a band of cardiac muscle, also covered by endocardium, known as the moderator band    (see [link] ) reinforces the thin walls of the right ventricle and plays a crucial role in cardiac conduction. It arises from the inferior portion of the interventricular septum and crosses the interior space of the right ventricle to connect with the inferior papillary muscle.

When the right ventricle contracts, it ejects blood into the pulmonary trunk, which branches into the left and right pulmonary arteries that carry it to each lung. The superior surface of the right ventricle begins to taper as it approaches the pulmonary trunk. At the base of the pulmonary trunk is the pulmonary semilunar valve that prevents backflow from the pulmonary trunk.

Left atrium

After exchange of gases in the pulmonary capillaries, blood returns to the left atrium high in oxygen via one of the four pulmonary veins. While the left atrium does not contain pectinate muscles, it does have an auricle that includes these pectinate ridges. Blood flows nearly continuously from the pulmonary veins back into the atrium, which acts as the receiving chamber, and from here through an opening into the left ventricle. Most blood flows passively into the heart while both the atria and ventricles are relaxed, but toward the end of the ventricular relaxation period, the left atrium will contract, pumping blood into the ventricle. This atrial contraction accounts for approximately 20 percent of ventricular filling. The opening between the left atrium and ventricle is guarded by the mitral valve.

Left ventricle

Recall that, although both sides of the heart will pump the same amount of blood, the muscular layer is much thicker in the left ventricle compared to the right (see [link] ). Like the right ventricle, the left also has trabeculae carneae, but there is no moderator band. The mitral valve is connected to papillary muscles via chordae tendineae. There are two papillary muscles on the left—the anterior and posterior—as opposed to three on the right.

The left ventricle is the major pumping chamber for the systemic circuit; it ejects blood into the aorta through the aortic semilunar valve.

Heart valve structure and function

A transverse section through the heart slightly above the level of the atrioventricular septum reveals all four heart valves along the same plane ( [link] ). The valves ensure unidirectional blood flow through the heart. Between the right atrium and the right ventricle is the right atrioventricular valve    , or tricuspid valve    . It typically consists of three flaps, or leaflets, made of endocardium reinforced with additional connective tissue. The flaps are connected by chordae tendineae to the papillary muscles, which control the opening and closing of the valves.

Questions & Answers

list down all the hormones secreted by adrenal gland
Odong Reply
The amount of blood pumped by the left ventricle of the heart in one contraction.
Javid Reply
how we can calculate the cardiac output
khater
and how do we calculate the strock valume
khater
stroke volume is not all the blood contained in the left ventricle; normally, only about two-thirds of the blood in the ventricle is expelled with each beat.
Javid
Cardiac output 5.5 l S. V 68.75 ml H. R 80bpm
Javid
If we consider SV 70, end systolic vol is about 15% of total(approx always) out of a total of 80-85 ml only 70ml is pumped per systole
Kartik
what is macrophages?and its function
Sajjad Reply
macrophages they are white blood cells that engulf dead cells in the body
patience
what is power stroke?
muravha
no idea
patience
what is the stroke volume of heart?
up
If an autoimmune disorder targets the alpha cells, production of which hormone would be directly affected?
Samantha Reply
what is a muscle?
Gideon Reply
A band or bundle of fibrous tissue in a human or animal body that has the ability to contract, producing movement in or maintaining the position of parts of the body
Mody
ok
Gideon
what's endolphthamities and panophthalmities?
Gideon
fluid around the brain
louise Reply
what ?
Asif
cerebro spinal fluid
Bhupender
The brain and spinal cord are surrounded by a clear fluid called cerebrospinal fluid (CSF). This fluid is produced and stored in cavities in the brain called ventricles. It circulatesaround the brain, moving from ventricle to ventricle. ... Hydrocephalus is a condition in which there is too much CSF
Archie
what is hydrocphalus
aminul Reply
Google krlena na madarchod yha maa chudwa rha ha sabko notification bhjke
Bhupender
when cerebrospinal fluid produce în the brain, i.e. brain ventricles, is to abundent in the brain and is not trăind out of the brain. as a consequence this lichid pute mechanical pressure oñ the brain and it pushes the cerebrum tissue. as a consequence this pressure on the neuronscan cause neurologi
Centerkinet
cal disfunctions, for example clinical headache
Centerkinet
. It is posible to drainout the fluid through a device dalles shunt,as i remember.
Centerkinet
but where are also home medicinsfor decreasing the production of cerebrospin.fluid etc
Centerkinet
there are some medicines that can decrease the production of csf
Centerkinet
a neurologist advice is needed
Centerkinet
i wrote some medicines NOT home medicines. it is a serious condition and specialized medical advice is needed. of course also general medical knowledge may be helpful, but not enough, a specialist is neede
Centerkinet
if anyone help me in physiology
Radika Reply
i am BSN student of first year which book is best for physiology
Radika
i am BSN student of first year which book is best for physiology
Radika
ross and wilson anotomy and physiology
Sajjad
it's 1 book for anotomy and physiology it's best for bs nursing
Sajjad
yes Ross and wilson physiology is better for study
Nasir
I'm also the student of bs nursing
Sajjad
I study guiton and hall &ganong
Gentle
I'm also midwif help me be the best book for midwif
nimco
what ia the function of indocrine system
sheraz
salam all friend
sheraz
help me with this question; explain at least five emergency acute pain found in fundamental emergency medicine
Christon
Fascial compartment of forearm
Hidayatullah
what's a tissue?
Mwape Reply
a group of cells with the same function
Dee
tissue is a group of cells that perform the same functions.
Rashid
explain a bit about a tissue
Mwape
A tissue is made up of cells that are similar in shape and perform the same function, for instance brain cells form up a brain tissue. Whereas a group of tissues that perform the same function form an organ... so in this case the brain which is the organ is formed as a result of brain tissues.
Isaac
what is gross anatomy
Joseph
the branch of anatomy that deals with the structure of organs and tissues that are visible to the naked eye.
Archie
1.To know how the structures functions. 2.To easily identify the micro structures and the macro structures. 3.To be able to explain that anatomy is the study of the structures and physiology is the study of how the structures functions
Abban Reply
Describe the two classes of hormones (3 with subclasses) and how they affect their target cells.
Shalaeha Reply
what is control centre
Gohil Reply
Angie The larger air passage of the lung is
Angie Reply
guys help to make me understand the structure of the skin
Olokojo Reply
the skin has three layers epidermis,dermis,and subcutaneous tissue
Antony
guys what is esrf
Antony
End Stage of Renal Failure
sheraz
what's the meaning of OPD
Sintung
Out Patient Department
Shahab
the skin has the assesory structures.that is, sebaceous glands, sweat glands, hairs, nails,blood vessels and lymph vessels.
Mutebe
yh
Gideon
define cell and give it's brief description of the orgenelles
Manish Reply
a cell is a basic unit of life
emmanuella
what about philosophy
Smart
the organelle is a membrane bound structure in the cell that performs a particular function
emmanuella
Cell.Is a basic functional unit of life. it has the organelles, Golgi apparatus, smooth endoplasmic membrane, rough endoplasmic reticular,Lysosomes, mitochondrial and others.
Mutebe

Get the best Anatomy & Physiology course in your pocket!





Source:  OpenStax, Anatomy & Physiology. OpenStax CNX. Feb 04, 2016 Download for free at http://legacy.cnx.org/content/col11496/1.8
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Anatomy & Physiology' conversation and receive update notifications?

Ask