1. There are two main types of somatic motor pathways - direct and indirect. Direct pathways transmit signals from the cerebral cortex to lower motor neurons, while indirect pathways involve additional structures like the basal ganglia and cerebellum.
2. Direct pathways include the corticospinal and corticobulbar tracts. Indirect pathways include the rubrospinal, tectospinal, vestibulospinal, lateral reticulospinal, and medial reticulospinal tracts.
3. Together these pathways coordinate voluntary and involuntary muscle movements through connections with lower motor neurons in the brainstem and spinal cord.
an overview of the ascending tract of the spinal cord....an anatomical approach to understand the somato-sensory pathway.
Prepared as a class presentation .
well describes the development of nervous system from basic to advanced concept including neural tube defects. the concepts are presented in graphical form for easy understanding of concepts.
an overview of the ascending tract of the spinal cord....an anatomical approach to understand the somato-sensory pathway.
Prepared as a class presentation .
well describes the development of nervous system from basic to advanced concept including neural tube defects. the concepts are presented in graphical form for easy understanding of concepts.
The all the content in this profile is completed by the teachers, students as well as other health care peoples.
thank you, all the respected peoples, for giving the information to complete this presentation.
this information is free to use by anyone.
Anatomy & functions of the Brainstem & CerebellumRafid Rashid
Provides a good description of the anatomy of the brainstem & cerebellum; their parts, structure, blood supply & a brief description of their functions.
This powerpoint was prepared to be presented at University of Health Sciences Cambodia for the Neurosurgery , Medicine and Psychiatry Residents, by shaweta khosa
The body's balance between acidity and alkalinity is referred to as acid-base balance. The blood's acid-base balance is precisely controlled because even a minor deviation from the normal range can severely affect many organs. The body uses different mechanisms to control the blood's acid-base balance.
Muscle spindles are proprioceptors that consist of intrafusal muscle fibers enclosed in a sheath (spindle). They run parallel to the extrafusal muscle fibers and act as receptors that provide information on muscle length and the rate of change in muscle length. The spindles are stretched when the muscle lengthens. This stretch causes the sensory neuron in the spindle to transmit an impulse to the spinal cord, where it synapses with alpha motor neurons. This causes activation of motor neurons that innervate the muscle. The muscle spindles determine the amount of contraction necessary to overcome a given resistance. When the resistance increases, the muscle is stretched further, and this causes spindle fibers to activate a greater muscle contraction.
Have you ever wondered why you sweat when you get too hot from running or shiver on a cold winter's day in this video we are going to explain why your body behaves like this.
Humans are endotherms and this means we are warm blooded we keep our body operating at thirty seven degrees Celsius regardless of the external conditions however this is a real challenge as our environment changes all the time depending on the weather, our clothes, if we are inside by the fire or outside having a snowball fight. So how does this work?
It's quite similar to the heating system in a house. in a house is a thermostat that measures the temperature if the house gets cold the thermostat will tell the radiators to turn on and heat it up if it's too hot they will be told to switch off simple.
Your body works in just the same way here in your brain as a special area called the hypothalamus and it measures the temperature of the blood flowing through it and also it collects information from temperatures senses around the body. it then decides if the temperature is too hot or too cold and we'll try and bring it back to thirty seven degrees Celsius. If you are too hot the hypothalamus can then send signals out to the body by the nervous system that can cause barriers to fact. It can send a signal to your skin and cool sweat glands to secrete the sweat on to the surface of the skin the sweat itself is not cold but it works because it takes the heat away from your body in order to evaporate it.
Another way of losing is vasodilation let kind of these blood vessels narrows this. That said the skin open white and allow blood to flow through them. They heat is radiated from the blood into the air and the blood cools down. If you get too cold you can do the opposite with these blood vessels and place them on keeping the blood away from the surface of the skin this is called vasoconstriction this is when your muscles contract in order to make. Another fact you may have noticed when you are cold against them. If you look more place the at least the Bulls what you realized is that each of the little bugger has a has to hit out at.
These has stood up on and struck a layer of air around the skin air is a fantastic insulate of heat and this will keep you nice and warm.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
Slide 1: Title Slide
Extrachromosomal Inheritance
Slide 2: Introduction to Extrachromosomal Inheritance
Definition: Extrachromosomal inheritance refers to the transmission of genetic material that is not found within the nucleus.
Key Components: Involves genes located in mitochondria, chloroplasts, and plasmids.
Slide 3: Mitochondrial Inheritance
Mitochondria: Organelles responsible for energy production.
Mitochondrial DNA (mtDNA): Circular DNA molecule found in mitochondria.
Inheritance Pattern: Maternally inherited, meaning it is passed from mothers to all their offspring.
Diseases: Examples include Leber’s hereditary optic neuropathy (LHON) and mitochondrial myopathy.
Slide 4: Chloroplast Inheritance
Chloroplasts: Organelles responsible for photosynthesis in plants.
Chloroplast DNA (cpDNA): Circular DNA molecule found in chloroplasts.
Inheritance Pattern: Often maternally inherited in most plants, but can vary in some species.
Examples: Variegation in plants, where leaf color patterns are determined by chloroplast DNA.
Slide 5: Plasmid Inheritance
Plasmids: Small, circular DNA molecules found in bacteria and some eukaryotes.
Features: Can carry antibiotic resistance genes and can be transferred between cells through processes like conjugation.
Significance: Important in biotechnology for gene cloning and genetic engineering.
Slide 6: Mechanisms of Extrachromosomal Inheritance
Non-Mendelian Patterns: Do not follow Mendel’s laws of inheritance.
Cytoplasmic Segregation: During cell division, organelles like mitochondria and chloroplasts are randomly distributed to daughter cells.
Heteroplasmy: Presence of more than one type of organellar genome within a cell, leading to variation in expression.
Slide 7: Examples of Extrachromosomal Inheritance
Four O’clock Plant (Mirabilis jalapa): Shows variegated leaves due to different cpDNA in leaf cells.
Petite Mutants in Yeast: Result from mutations in mitochondrial DNA affecting respiration.
Slide 8: Importance of Extrachromosomal Inheritance
Evolution: Provides insight into the evolution of eukaryotic cells.
Medicine: Understanding mitochondrial inheritance helps in diagnosing and treating mitochondrial diseases.
Agriculture: Chloroplast inheritance can be used in plant breeding and genetic modification.
Slide 9: Recent Research and Advances
Gene Editing: Techniques like CRISPR-Cas9 are being used to edit mitochondrial and chloroplast DNA.
Therapies: Development of mitochondrial replacement therapy (MRT) for preventing mitochondrial diseases.
Slide 10: Conclusion
Summary: Extrachromosomal inheritance involves the transmission of genetic material outside the nucleus and plays a crucial role in genetics, medicine, and biotechnology.
Future Directions: Continued research and technological advancements hold promise for new treatments and applications.
Slide 11: Questions and Discussion
Invite Audience: Open the floor for any questions or further discussion on the topic.
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Since volcanic activity was first discovered on Io from Voyager images in 1979, changes
on Io’s surface have been monitored from both spacecraft and ground-based telescopes.
Here, we present the highest spatial resolution images of Io ever obtained from a groundbased telescope. These images, acquired by the SHARK-VIS instrument on the Large
Binocular Telescope, show evidence of a major resurfacing event on Io’s trailing hemisphere. When compared to the most recent spacecraft images, the SHARK-VIS images
show that a plume deposit from a powerful eruption at Pillan Patera has covered part
of the long-lived Pele plume deposit. Although this type of resurfacing event may be common on Io, few have been detected due to the rarity of spacecraft visits and the previously low spatial resolution available from Earth-based telescopes. The SHARK-VIS instrument ushers in a new era of high resolution imaging of Io’s surface using adaptive
optics at visible wavelengths.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
1. Somatic Motor Pathways|
Pyramidal & Extrapyramidal Tracts|
Descending Tracts of spinal cord
FATIMA WAHID MANGRIO
fatimawahid1234@gmail.com
2. Somatic Motor Pathways
• Neural circuits in the brain and spinal cord
orchestrate all voluntary and involuntary movements.
• All excitatory and inhibitory signals that control
movement converge on the motor neurons.
• These neurons, also known as lower motor neurons
(LMNs), have their cell bodies in the brain stem and
spinal cord.
• From the brain stem, axons of LMNs extend through
cranial nerves to innervate skeletal muscles of the
face and head.
3. • From the spinal cord, axons of LMNs extend through
spinal nerves to innervate skeletal muscles of the
limbs and trunk.
• Only LMNs provide output from the CNS to skeletal
muscle fibers. For this reason, they are also called
the final common pathway
4. • Neurons in four distinct neural circuits, control of
movement by providing input to lower motor neurons.
1 Local circuit neurons
• Input arrives at lower motor neurons from nearby
interneurons called local circuit neurons. These
neurons are located close to the lower motor neuron
cell bodies in the brain stem and spinal cord.
• Local circuit neurons receive input from somatic
sensory receptors, such as nociceptors and muscle
spindles, as well as from higher centers in the brain.
They help coordinate rhythmic activity in specific
muscle groups, such as alternating flexion and
extension the lower limbs during walking.
5. 2 Upper motor neurons
• Both local circuit neurons and lower motor neurons
receive input from upper motor neurons (UMNs).
• Most upper motor neurons synapse with local circuit
neurons, which in turn synapse with lower motor
neurons. (A few upper motor neurons synapse directly
with lower motor neurons.)
• UMNs from the cerebral cortex are essential for the
execution of voluntary movements of the body.
6. • Other UMNs originate in motor centers of the brain
stem: the red nucleus, the vestibular nucleus, the
superior colliculus, and the reticular formation. UMNs
from the brain stem regulate muscle tone,control
postural muscles, and help maintain balance and
orientation of the head and body.
• Both the basal nuclei and cerebellum exert influence
on upper motor neurons.
7. 3 Basal nuclei neurons
• Basal nuclei neurons assist movement by providing
input to upper motor neurons.
• Neural circuits interconnect the basal nuclei with
motor areas of the cerebral cortex (via the thalamus)
and the brain stem. These circuits help initiate and
terminate movements, suppress unwanted movements,
and establish a normal level of muscle tone.
8. 4 Cerebellar neurons
• Cerebellar neurons also aid movement by controlling
the activity of upper motor neurons.
• Neural circuits interconnect the cerebellum with
motor areas of the cerebral cortex (via the thalamus)
and the brain stem.
• A prime function of the cerebellum is to monitor
differences between intended movements and
movements actually performed.
• Then, it issues commands to upper motor neurons to
reduce errors in movement.
• The cerebellum thus coordinates body movements
and helps maintain normal posture and balance.
9.
10. Organization of Upper Motor Neuron
Pathways
• The axons of upper motor neurons extend from the brain
to lower motor neurons via two types of somatic motor
pathways—direct and indirect.
• Direct motor pathways provide input to lower motor
neurons via axons that extend directly from the cerebral
cortex.
• Indirect motor pathways provide input to lower motor
neurons from motor centers in the basal nuclei,
cerebellum, and cerebral cortex.
11. Direct Motor Pathways
( Pyramidal pathway )
• Nerve impulses for voluntary movements propagate
from the cerebral cortex to lower motor neurons via
the direct motor pathways.
• The direct motor pathways, which are also known as
the pyramidal pathways, consist of axons that
descend from pyramidal cells. Pyramidal cells are
upper motor neurons with pyramid shaped cell bodies
located in the primary motor area and the premotor
area of the cerebral cortex (areas 4 and 6 ).
• The direct motor pathways consist of
12. Corticospinal Pathways
• The corticospinal pathways conduct impulses for the
control of muscles of the limbs and trunk.
• Axons of upper motor neurons in the cerebral cortex
form the corticospinal tracts, which descend through
the internal capsule of the cerebrum and the cerebral
peduncle of the midbrain.
• In the medulla oblongata, the axon bundles of the
corticospinal tracts form the ventral bulges known as
the pyramids. About 90% of the corticospinal axons
decussate to the contralateral (opposite) side in the
medulla oblongata and then descend into the spinal
cord where they synapse with a local circuit neuron or
a lower motor neuron.
13. • The 10% that remain on the ipsilateral (same) side
eventually decussate at the spinal cord levels where
they synapse with a local circuit neuron or lower
motor neuron.
• Thus, the right cerebral cortex controls most of the
muscles on the left side of the body, and the left
cerebral cortex controls most of the muscles on the
right side of the body.
• There are two types of corticospinal tracts:
14. 1 Lateral corticospinal tract
• Corticospinal axons that decussate in the medulla
form the lateral corticospinal tract in the lateral
white column of the spinal cord .
• These axons synapse with local circuit neurons or
lower motor neurons in the anterior gray horn of the
spinal cord.
• Axons of these lower motor neurons exit the cord in
the anterior roots of spinal nerves and terminate in
skeletal muscles that control movements of the distal
parts of the limbs.
• The distal muscles are responsible for precise, agile,
and highly skilled movements of the hands and feet.
Examples include the movements needed to button a
shirt or play the piano
15.
16. 2 Anterior corticospinal tract.
• Corticospinal axons that do not decussate in the
medulla form the anterior corticospinal tract in the
anterior white column of the spinal cord
• At each spinal cord level, some of these axons
decussate via the anterior white commissure. Then,
they synapse with local circuit neurons or lower motor
neurons in the anterior gray horn.
• Axons of these lower motor neurons exit the cord in
the anterior roots of spinal nerves. They terminate in
skeletal muscles that control movements of the trunk
and proximal parts of the limbs.
17.
18. Corticobulbar Pathway
• The corticobulbar pathway conducts impulses for the
control of skeletal muscles in the head.
• Axons of upper motor neurons from the cerebral
cortex form the corticobulbar tract, which descends
along with the corticospinal tracts through the
internal capsule of the cerebrum and cerebral
peduncle of the midbrain.
19. • Some of the axons of the corticobulbar tract
decussate; others do not. The axons terminate in the
motor nuclei of nine pairs of cranial nerves in the
brain stem: the oculomotor (III), trochlear (IV),
trigeminal (V), abducens (VI), facial (VII),
glossopharyngeal (IX), vagus (X), accessory (XI), and
hypoglossal (XII).
• The lower motor neurons of the cranial nerves convey
impulses that control precise, voluntary movements of
the eyes, tongue, and neck, plus chewing, facial
expression, speech, and swallowing.
20.
21. Indirect Motor Pathways
• The indirect motor pathways or extrapyramidal
pathways include all somatic motor tracts other than
the corticospinal and corticobulbar tracts.
• Axons of upper motor neurons that give rise to the
indirect motor pathways descend from various nuclei
of the brain stem into five major tracts of the spinal
cord and terminate on local circuit neurons or lower
motor neurons.
22. • These tracts are the
1 rubrospinal
2 tectospinal
3 vestibulospinal
4 lateral reticulospinal
5 medial reticulospinal tracts
23. RUBROSPINAL TRACT
• Conveys nerve impulses from red nucleus (which
receives input from cerebral cortex and cerebellum)
to contralateral skeletal muscles that govern precise,
voluntary movements of distal parts of upper limbs.
• The rubrospinal tract is small in humans and
terminates in the cervical cord. It is thought to be
responsible for taking over functions after
corticospinal tract injury and may also play a role in
flexor or decorticate posturing in the upper
extremities with lesions above the level of the red
nucleus in which the rubrospinal tract is preserved.
24.
25. Tectospinal & Reticulospinal Tract
• Conveys nerve impulses from superior colliculus to
contralateral skeletal muscles that reflexively move
head, eyes, and trunk in response to visual or auditory
stimuli.
• The final two descending motor pathways are the
tectospinal tract, terminating in the cervical cord,
and the reticulospinal tract, terminating along the
entire cord. The tectospinal tract is responsible for
coordination of head and eye movements, and this is
poorly understood in humans. The reticulospinal tract
is responsible for automatic posture and gait-related
movements.
26.
27. Vestibulospinal Tract
• Conveys nerve impulses from vestibular nucleus
(which receives input about head movements from
inner ear) to ipsilateral skeletal muscles of trunk and
proximal parts of limbs for maintaining posture and
balance in response to head movements.
• the vestibulospinal tract with medial fibers
terminating in the cervical and upper thoracic cord
and lateral portions, which are still considered part of
the medial system, terminating in the entire cord.
Vestibulospinal tracts are responsible for positioning
of the head and neck (the medial fibers) and balance
(the lateral fibers).
28.
29. Medial and lateral reticulospinal
Tract
• Conveys nerve impulses from reticular formation to
ipsilateral skeletal muscles of trunk and proximal
parts of limbs for maintaining posture and regulating
muscle tone in response to ongoing body movements.