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The study biological systems in regards to their ability to apply and respond to mechanical forces.

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Tensile strength of collagen?

Really specific question, but what is the average tensile strength of human collagen, type I? I've tried looking for it online, and either my google-fu skills are weak, or I'm just unlucky. Also, is ...
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about the muscle's tension's variables

I'm reading the paper "THE PROBLEM OF THE INTERRELATION OF CO-ORDINATION AND LOCALIZATION", which is written by N. Bernstein. The paper said "The degree of tension of a muscle is a function, in the ...
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Why is the passive component in a Hill-type muscle modeled as an exponential?

A Hill-Type muscle model has a contractile element and a passive component in parallel as well as a passive component in series. Equations for this model that I've seen (e.g. Blumel 2012) use an ...
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47 views

Bite Force of Triceratops

Estimations (or measurements) of bite force is usually conducted for toothy predators like sharks, theropod dinosaurs and crocodiles. For example: Tyrannosaurus had a bite force of about 57 kN (about ...
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How are ants able to dig with such pointy limbs?

Digging is usually efficient with somewhat broader structures shovels, no one tries to shovel with an ice-pick. Given that ants have very pointy mandibles and thin wispy legs, how are they able to dig ...
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Reference for the bite force for Nile Crocodile

The (maximal) bite force of the Nile Crocodile (Crocodylus niloticus) is estimated around 22,000 Newton (refer to YouTube interview with Ofer Kobi, a crocodile conservation ranger and croc farm owner, ...
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1answer
14 views

How are the helices of MscL gating “attached”?

I'm attempting to model the mechanosensitive channels of large conductance (MscL) in E. coli for finite element analysis purposes. I have a number of papers where this has been done, and one shows the ...
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1answer
70 views

What is the purpose of the viscous gel in the Pacinian corpuscle?

I have read that 'when the stimulus (in this case pressure) is constantly applied, the gel repositions itself to prevent the formation of an action potential'. I don't really understand what this ...
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How does fungi network transfer substances between plants?

How does fungi network transfer substances between plants? I recently read a short article about fungi network. And I am wondering about how fungi network works (Mechanism). Plants have fungi ...
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31 views

Are there biological ratchet cycles that are small in number?

I recently came across the strange factoid that all animals that can jump do so to roughly the same height (within an order of magnitude). The argument was that the work done by muscles in a single ...
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316 views

Strongest bone in body

AS internet tells is it is thigh bone which is strongest, but why, it carry only upper part of body, does not heel or any foot bones should be strongest in body as they carry full body weight ?
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20 views

Muscle involved in carrying load on head

I have seen people carrying heavy load on their head especially in 3rd world countries, does carrying on head any benefit or harm, which muscle get strengthen in doing it?
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44 views

Are trees still carrying their leaves more likely to be felled by an autumn storm?

Is there evidence that trees still carrying their leaves are more likely to be felled by an autumn storm than trees already having lost their leaves? At first sight this seems plausible (and might be ...
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1answer
31 views

What’s the term used to define a terrestrial being that moves by using six limbs?

I know that Bipedal locomotion would describe how beings like humans and ostriches get around. Quadrupedal locomotion describes how beings like dogs and cats move around. What about insects, ...
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1answer
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How did the largest/longest dinosaurs hold their head and necks up?

After seeing the images in the articles shown below, I am having a tough time understanding the mechanics of how these incredibly long and heavy necks can be supported outstretched like this. A rigid ...
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1answer
122 views

Any simulations of four-winged dinosaur flight? (microraptors)

This week's podcast of the BBC's Science in Action includes a section by Rory Galloway (12:20 to 18:30) covering the Dinosaurs ...
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273 views

Curved membrane effect

Curved Membrane effect: Movements of the tympanic membrane are more at the periphery than at the centre where malleus is attached which provides some leverage. This is called as curved membrane ...
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0answers
91 views

Three foramen lying in one vertical plane

In the human skull we can see that 3 foramina named as supraorbital notch(foramen) , infraorbital foramen and mental foramen share a common vertical plane. Is there any surgical significance of for ...
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How is the Force of Contraction Applied to the Tendons by the Muscle's Individual Fibers?

Image and question have been updated for clarity! The image above is a side view of a semi-transparent skeletal muscle. The dark red lines represent individual fibers, the blue lines represent ...
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How pulmonary vasculature removes embolism?

This book says: Pulmonary vasculature removes emboli before they reach into systemic circulation. I can speculate that if the emboli are made of fat or clot then our body could degrade it but how ...
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2answers
200 views

Why metacarpus is considered hand proper?

This textbook states The hand (or manus) consists of the following parts: (a) wrist or carpus, (b) hand proper (or metacarpus), and (c) digits (thumb and fingers). How could I justify why are ...
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72 views

How can skeletal muscles in the human body be modeled as levers? [closed]

From what I understand, human arms can be thought of as third class levers, so that the distance from your elbow to the place where the muscle attaches is effectively the distance to the fulcrum, so ...
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1answer
9k views

Why do we have the tibia and fibula (a 2nd bone) in the lower leg?

Does fibula participate in rotational movement of ankle or not (just like the radius in forearm)? If not, what is the purpose of that bone?
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2answers
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Are humans done changing?

I thought that massive changes among organisms are over long periods of time. This is caused by, to my knowledge: Evolutionary pressure Natural/artificial selection Mutations Genetic drift Will ...
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1answer
157 views

How does the brain alter/inhibit muscle reflexes?

I can find lots of information on how stretch-reflexes/reciprocal-inhibition/autogenic-inhibition work but from them all it's unclear how exactly the brain interfaces/controls/disables such automatic ...
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Mechanics of Peregrine Falcon Dive Pull Up

There are loads of information on how fast the Peregrine Falcon dives, but aside from having specialized lungs, eyes, etc... to survive the dive. What mechanics does it use to pull out of such a dive,...
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1answer
90 views

What is the acceleration profile of the greyhound?

I'm interested in the acceleration curve over time that's typical of an adult greyhound prior to attaining this peak velocity. My curiosity is motivated by a desire to understand the biomechanical ...
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1answer
67 views

What is the acceleration profile of a cheetah?

I'm interested in the time it takes for a cheetah to reach maximum velocity as well as the acceleration over time that's typical of a cheetah prior to attaining this peak velocity.
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1answer
136 views

How is a synapse held in place?

Here is a question I've never asked myself until now: All textbooks show synapses with a decently large synaptic cleft between the axon terminal and the dendrite. How is this connection held in place ...
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1answer
656 views

How fast is the patellar reflex?

I have found a lot of content on the patellar reflex, but I cannot find any studies on how fast the reflex is, from onset of stimulus to innervation of muscles. Does anyone know of either a study or ...
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1answer
14k views

How do disulphide bonds in hair cause curling?

I understand that there are several characteristics of curly hair which differ from straight hair (such as an asymmetrical distribution of disulphide bonds in curly hair), but really am struggling to ...
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2answers
1k views

Are there any predators without camouflage?

Are there any predators that don't use camouflage?
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1answer
83 views

How do proteins perform their function [closed]

I have asked a question on physics stackexchange, but was redirected here. I copy the entire question word for word. The original is here. Let's, for example, take a ribosome. It is an enzyme that is ...
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1answer
468 views

Can geckos climb a wet surface?

We know geckos can climb vertically or even upside down a surface like glass. But can they do that on wet glass?
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2answers
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Which part of human body sustains most pressure when standing up straight?

Let's suppose a healthy fit barefoot young adult standing comfortably on a flat solid surface. A reasonable guess is somewhere around the foot. But is it the ankle, the heel, or the Metatarsus?
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1answer
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Why do flagella form a bundle only when they rotate counterclockwise during chemotaxis?

During Chemotaxis in bacteria with flagella, the flagellar rotation dictates how the cell moves. If the flagella rotate counterclockwise, then they form a bundle at one end of the cell (---O) and ...
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51 views

How does trees know to balance themselves so that they never fall down [duplicate]

Well i was flying kites today I saw a tree and its branches were spread around in random directions... I would like to know that how do these trees know to nourish their branches in some direction so ...
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2answers
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How do marine mammals control buoyancy?

Presumably, as a whale or seal dives, its lungs get compressed by the increasing water pressure, and it gets less buoyant. Under this model, for a given amount of air taken in at the surface, the ...
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1answer
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How fast can a human run?

I'm a runner (cross country) and I'm always amazed at how fast Olympic sprinters are. There's a lot of hype about those in the 100-meter dash being the fastest in the world, and we're constantly ...
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force required to do damage to child's leg/feet in collision [closed]

I'm currently working on a toy robot for a student project. Part of this robot is the fact that it will be moving around quite fast. As such hitting the child can and most likely will happen. As such ...
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2answers
1k views

What are the buoyancy control mechanisms of Chambered nautilus?

I'm currently working on an underwater robot and was hoping to use the principle used by the nautilus for buoyancy control. So how do the Chambered nautilus control its buoyancy?
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2answers
346 views

Can jellyfish swim backwards?

Jellyfish use jet propulsion to move forward, according to http://earthsky.org/earth/how-do-jellyfish-swim. Otherwise, they drift with the ocean currents. Does this mean that, without the presence of ...