Answer:
A myosin head bound to actin
Explanation:
Cross bridge cycling explains the sliding filament theory according to which thin and thick filament slide against each other for muscle contraction. The two myosin heads extend form the thick filament. One myosin head has binding site for ATP and other head has binding site for actin from thin filament.
When myosin head binds to actin a cross bridge is formed. When ATP binds to the other head the bridge dissociates. Actin binding site is free and myosin tries to bind with other actin during which ATP is hydrolysed into ADP and Pi. Myosin along with the ADP and free Pi successfully binds to another actin molecule. The cross bridge formed generates a powerful force and ADP and Pi are displaced from it. The cross bridge is now free again for binding of next ATP molecule and the cycle continues.
The right answer is the second one
Producers generally require sunlight to make energy. Since there isn't sunlight at the bottom of the lake, they are unable to photosynthesize and produce energy they need to survive.
Some of the equipment the student can use are:
Nets
Underwater cameras
pH indicators
among others.
<h3>What does the student want to study?</h3>
The student wants to find out if there are invertebrates and fish or if the conditions of the pond would support these types of organisms.
<h3>What does the student need to do?</h3>
In this situation, there are two main approaches:
- Study invertebrates and fish: This approach implies finding out if there are already invertebrates and fish in the pond, to do this, the student can
- Directly observe organisms by using a special camera.
- Use a net to catch organisms in the pond and then classify the organisms.
- Study the conditions: This approach implies determining if the pond has the conditions for invertebrates and fish to live. To do this, the student will need to measure conditions such as:
- Nutrients in the pond.
- Temperature.
- Ph.
This will require equipment such as pH indicators.
Learn more aobut pH in: brainly.com/question/491373
<span>Pacinian corpuscles are rapidly adapting mechanoreceptors so they respond only at the onset and offset of the stimulus. The Pacinian corpuscle has a single afferent nerve fiber. Its end is covered by a sensitive receptor membrane whose sodium channels will open when the membrane is deformed in any way. Pressure thus causes sodium to enter the neuron and create a generator potential. If this potential reaches a certain threshold nerve impulses are formed. This impulse is now transferred along the axon with the use of sodium channels and sodium/potassium pumps in the axon membrane. The magnitude of the stimulus is encoded in the frequency of impulses generated in the neuron. So the more massive or rapid the deformation of a single corpuscle, the higher the frequency of nerve impulses generated in its neuron.</span>
