scholarly journals Ancestral form and function of larval feeding structures are retained during development of non-planktotrophic gastropods

2020 ◽  
Vol 52 ◽  
Author(s):  
Rachel Collin ◽  
Caitlin M. Shishido ◽  
Anabell J. Cornejo ◽  
Maryna P. Lesoway
Keyword(s):  
Marine Invertebrates ◽  
The Body ◽  
Larval Feeding ◽  
Complex Structures ◽  
Video Footage ◽  
Form And Function ◽  
Body Sizes ◽  
Planktotrophic Larvae ◽  
Mode Of Development ◽  
And Function

Mode of development (MOD) is a key feature that influences the rate and direction of evolution of marine invertebrates. Although many groups include species with different MODs, the evolutionary loss of feeding larvae is thought to be irreversible as the complex structures used for larval feeding and swimming are lost, reduced, or modified in many species lacking feeding larvae. This view is largely based on observations of echinoderms. Phylogenetic analysis suggests that feeding larvae have been re-gained in at least one species of calyptraeid gastropod. Further, its sister species has retained the velum, the structure used for larval feeding and swimming. Here, we document velar morphology and function in calyptraeids with 4 different MODs. Embryos of Crepidula navicella, Crepidula atrasolea, Bostrycapulus aculeatus, Bostrycapulus odites, Bostrycapulus urraca, Crepipatella dilatata, Crepipatella occulta, Crucibulum quiriquinae and Crepidula coquimbensis all hatch as crawling juveniles, yet only Crepidula coquimbensis does not make a well-formed velum during intracapsular development. The velar dimensions of 6 species with non-planktotrophic development were similar to those of planktotrophic species, while the body sizes were significantly larger. All of the species studied were able to capture and ingest particles from suspension, but several non-planktotrophic species may ingest captured particles only occasionally. Video footage suggests that some species with adelphophagic direct development capture but frequently fail to ingest particles compared to species with the other MODs. Together these lines of evidence show that, among calyptraeids at least, species that lack planktotrophic larvae often retain the structures and functions necessary to successfully capture and ingest particles, reducing the barriers to the re-evolution of planktotrophy.

Mechanobiology and Adaptive Plasticity (MAP) Theory as a Potential Confounding Factor in Predicting Musculoskeletal Foot Function

2021 ◽  
Author(s):  
Greg Quinn
Keyword(s):  
Physical Nature ◽  
Theoretical Models ◽  
The Body ◽  
Adaptive Plasticity ◽  
Form And Function ◽  
Complex Processes ◽  
Kinetic Information ◽  
Foot Function ◽  
Clinical Variation ◽  
And Function

There are many theoretical models that attempt to accurately and consistently link kinematic and kinetic information to musculoskeletal pain and deformity of the foot. Biomechanical theory of the foot lacks a consensual model: clinicians are enticed to draw from numerous paradigms, each having different levels of supportive evidence and contrasting methods of evaluation, in order to engage in clinical deduction and treatment planning. Contriving to find a link between form and function lies at the heart of most of these competing theories and the physical nature of the discipline has prompted an engineering approach. Physics is of great importance in biology and helps us to model the forces that the foot has to deal with in order for it to work effectively. However, the tissues of the body have complex processes that are in place to protect them and they are variable between individuals. Research is uncovering why these differences exist and how these processes are governed. The emerging explanations for adaptability of foot structure and musculoskeletal homeostasis offer new insights on how clinical variation in outcomes and treatment effects might arise. These biological processes underlie how variation in the performance and utilisation of common traits, even within apparently similar sub-groups, make anatomical distinction less meaningful and are likely to undermine the justification of a 'foot type'. Furthermore, mechanobiology introduces a probabilistic element to morphology based on genetic and epigenetic factors.

scholarly journals A Historical Review of Enzymatic Debridement: Revisited

2019 ◽  
Author(s):  
Brett David W
Keyword(s):  
Wound Care ◽  
Historical Review ◽  
The Body ◽  
Form And Function ◽  
Bacterial Collagenase ◽  
History Of ◽  
Biochemical Research ◽  
The Many ◽  
And Function ◽  
Enzymatic Debridement

The following is an update to a book entitled, “A Historical Review of Enzymatic Debridement: Revisited”, which I wrote in 2003. Since its publication, while the relevant clinical evidence has remained consistent, the amount of biochemical research and knowledge gained has been impressive. In the first chapter a sampling of the typical topical enzymatic debriding agents that have been used in wound care are reviewed and interestingly enough only one remains on the market. The FDA has removed all others from the marketplace and an explanation is provided in chapter one along with descriptions of the use and mode of action (MoA) of these agents. Chapter two is a review of the many different types of collagen found in the body, including their structure, form, and function as so much additional insight into this molecule has been gained since 2003. In chapter three we see an account depicting the many advances in understanding matrix metalloproteinases (MMPs) reviewed in detail. Form, function, tissue orientation and preferred substrates are addressed. Finally, in chapter four we see the history of the MoA of MMPs as compared to bacterial collagenase starting in the early ‘80s to the time of this current publication. In addition we see the level of complexity of bacterial collagenases compared to MMPs, helping us to better understand why bacterial collagenase is much more efficient at removing necrotic tissue from wounds than are our own (endogenous) MMPs. I hope the reader finds this review useful from an academic standpoint, but more importantly from a clinical framework helping to understand the role of these types of therapies in wound care.

scholarly journals GrassView - the form and function of grass: a multimedia program

2013 ◽  
pp. 141-143
Author(s):  
E.P. Ashley ◽  
C. Matthew ◽  
J. Hodgson
Keyword(s):  
3D Animation ◽  
Interactive Mode ◽  
Linear Mode ◽  
Video Footage ◽  
Form And Function ◽  
Graphical Displays ◽  
Multimedia Program ◽  
Computer Based ◽  
And Function ◽  
Leaf Extension

GrassView - the form and function of grass is an interactive computer programme which uses video footage, narration, sound, computer based 3D animation, graphical displays of information, charts and quizzes to present a description of the morphology of a grass tiller and the implications for sward behaviour. The programme is designed for flexibility of use. In interactive mode it could be used for self-directive study, whereas in linear mode it could be video-projected as a presentation to a class of students or to an assembled group. It has been optimised to run under Windows 95 or NT 4.0 and is distributed as a CD. Keywords: computer program, grass form and function, grass morphology, interactive program, leaf extension,

scholarly journals The Antitrochanter of Birds: Form and Function in Balance

The Auk ◽  
2007 ◽  
Vol 124 (3) ◽  
pp. 789-805 ◽  
Author(s):  
Fritz Hertel ◽  
Kenneth E. Campbell
Keyword(s):  
Hip Joint ◽  
Spatial Orientation ◽  
Good Predictor ◽  
Bipedal Locomotion ◽  
Terrestrial Locomotion ◽  
Form And Function ◽  
Wide Range ◽  
Body Sizes ◽  
Position And Orientation ◽  
And Function

AbstractThe antitrochanter is a uniquely avian osteological feature of the pelvis that is located lateral to the postero-dorsal rim of the acetabulum. This feature makes the avian hip joint unique among all vertebrates, living and fossil, in that a significant portion of the femoral-pelvic articulation is located outside of the acetabulum. This additional acetabular articulation occurs between the neck of the femur and the antitrochanter, and operates as a hinge joint or ginglymus. It is complementary to the articulation of the head of the femur with the acetabulum, which is a pivot joint or trochoides. The size, location, and spatial orientation of the antitrochanter were determined for 77 species of birds representing a variety of hindlimb functions (e.g., highly cursorial, vertical clinging, foot-propelled diving) and spanning a wide range of body sizes (swifts to rheas). The area of the antitrochanter is a good predictor of body mass in birds; its position and orientation are reasonably consistent within hindlimb morphofunctional groups, but not among all birds. The antitrochanter serves as a brace to prevent abduction of the hindlimb and to absorb stresses that would otherwise be placed on the head of the femur during bipedal locomotion. The drum-in-trough-like form of the antitrochanter-femur articulation tends to assist in the transfer of long-axis rotational movements of the femur to the pelvis. The avian antitrochanter is a derived feature of birds that evolved as an aid in maintaining balance during bipedal terrestrial locomotion.El Antitrocánter en las Aves: Forma y Función en el Equilibrio

scholarly journals Prosthetic Considerations in Oral and Maxillofacial Trauma

2014 ◽  
Vol 48 (2) ◽  
pp. 87-90 ◽  
Author(s):  
Sudhir Bhandari
Keyword(s):  
The Body ◽  
The Other ◽  
Maxillofacial Trauma ◽  
Maxillofacial Region ◽  
Form And Function ◽  
Life Threatening ◽  
Oral And Maxillofacial Region ◽  
And Function

ABSTRACT Intraoral trauma may occur in isolation or in combination with injury of the other parts of the body. Once the life-threatening phase of trauma is over, the primary need for the patient is to restore the form and function of the tissues lost due to trauma. In the oral and maxillofacial region, esthetic consideration does sometimes supersede the need of function. This article briefl y summarizes the scope of prosthodontics in patients with oral and maxillofacial trauma. How to cite this article Bhandari S. Prosthetic Considerations in Oral and Maxillofacial Trauma. J Postgrad Med Edu Res 2014; 48(2):87-90.

scholarly journals Decussation as an axial twist: A Comment on Kinsbourne (2013)

2017 ◽  
Author(s):  
Marc HE de Lussanet ◽  
Jan W.M. Osse
Keyword(s):  
The Body ◽  
Form And Function ◽  
Efferent Connections ◽  
Similarities And Differences ◽  
And Function ◽  
Axial Twist ◽  
The Brain ◽  
Rostral Part

One of the great mysteries of the brain, which has puzzled all-time students of brain form and function is the contralateral organization of the forebrain, and the crossings of its major afferent and efferent connections. As a novel explanation, two recent studies have proposed that the rostral part of the head, including the forebrain, is rotated by 180 degrees with respect to the rest of the body (de Lussanet and Osse, 2012, Animal Biology 62, 193–216; Kinsbourne, 2013, Neuropsychology 27, 511–515). Kinsbourne proposes one 180-degree turn while we consider the 180 degrees being the result of two 90-degree turns in opposite directions. We discuss the similarities and differences between the two hypotheses.

scholarly journals Ontogenetic scaling of hydrostatic skeletons: geometric, static stress and dynamic stress scaling of the earthworm lumbricus terrestris

1998 ◽  
Vol 201 (12) ◽  
pp. 1871-1883 ◽  
Author(s):  
KJ Quillin
Keyword(s):  
Body Size ◽  
Body Wall ◽  
Dynamic Stress ◽  
Lumbricus Terrestris ◽  
Static Stress ◽  
The Body ◽  
Cross Sectional ◽  
Dynamic Stresses ◽  
Form And Function ◽  
And Function

Soft-bodied organisms with hydrostatic skeletons range enormously in body size, both during the growth of individuals and in the comparison of species. Therefore, body size is an important consideration in an examination of the mechanical function of hydrostatic skeletons. The scaling of hydrostatic skeletons cannot be inferred from existing studies of the lever-like skeletons of vertebrates and arthropods because the two skeleton types function by different mechanisms. Hydrostats are constructed of an extensible body wall in tension surrounding a fluid or deformable tissue under compression. It is the pressurized internal fluid (rather than the rigid levers of vertebrates and arthropods) that enables the maintenance of posture, antagonism of muscles and transfer of muscle forces to the environment. The objectives of the present study were (1) to define the geometric, static stress and dynamic stress similarity scaling hypotheses for hydrostatic skeletons on the basis of their generalized form and function, and (2) to apply these similarity hypotheses in a study of the ontogenetic scaling of earthworms, Lumbricus terrestris, to determine which parameters of skeletal function are conserved or changed as a function of body mass during growth (from 0.01 to 8 g). Morphometric measurements on anesthetized earthworms revealed that the earthworms grew isometrically; the external proportions and number of segments were constant as a function of body size. Calculations of static stresses (forces per cross-sectional area in the body wall) during rest and dynamic stresses during peristaltic crawling (calculated from measurements of internal pressure and body wall geometry) revealed that the earthworms also maintained static and dynamic stress similarity, despite a slight increase in body wall thickness in segment 50 (but not in segment 15). In summary, the hydrostatic skeletons of earthworms differ fundamentally from the rigid, lever-like skeletons of their terrestrial counterparts in their ability to grow isometrically while maintaining similarity in both static and dynamic stresses.

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