Use Models 1-4 to put the following events in order from the signal from the brain reaching a muscle to the contraction of the whole muscle. •Myosin bends in two places, releasing ADP and pulling on the thin filament.
•The nerve impulse reaches the end of the nerve and causes it to release acetylcholine (Ach)
•An electrical impulse travels down a nerve fiber
•The Z-lines are pulled closer together and the A-band shrinks
•Ach bonds to receptors on the muscle cell membrane and causes the electrical impulse to be transmitted to the muscle cell
•Calcium ions bind to troponin causing it to rotate
•The myofibril gets shorter (contracts)
•The electrical impulse inside the muscle cell causes the release of calcium ions from the endoplasmic reticulum
•Rotation of troponin move tropomyosin off of the myosin binding site on actin
•The myosin head binds the myosin binding domain of actin

Which type of bacterial reproduction is depicted in the diagram?

Complete the sentences by matching the names of trees to the appropriate blanks. to do this, drag the names on the left into the appropriate blanks in the sentences on the right. match the words in the left column to the appropriate blanks in the sentences on the right. terms may be used more than once. make certain you have filled every blank with a term before clicking submit. 1. deciduous trees lose their leaves seasonally and include trees such as maple and elm. 2. conifer leaves are generally thin and needle-like, while seeds are contained in cones. conifers include cedar and pine. 3. evergreens are plants that maintain their leaves in all seasons and include trees such as cedar, elm, and pine. 4. hardwoods reproduce using flowers and have broad leaves; hardwoods include trees such as maple, , and cedar. elm returned you filled in 2 of 10 blanks incorrectly. mango trees are tropical broad leaf plants that maintain their leaves all year long. no credit lost. try again.

The energy required to vaporize a certain amount of a substance is greater than the amount of energy necessary to raise the temperature of the same amout of that substance by 1 degreee celcius