Arrange these muscle contraction events in the correct order. 1. nerve stimulus
2. myosin attaches to actin causing a twitch
3. acetylcholine binds to receptor
4. calcium channels open
5. sarcoplasmic reticulum releases calcium
6. impulse rides along sarcolemma
7. exocytosis occurs releasing acetylcholine into synaptic cleft
8. calcium binds to troponin moving tropomyosin out of the way
9. impulse enters the cells via the t-tubule
10. acetylcholine vesicles move to endplate

ecological efficiency: % of usable energy transferred as

biomass from one trophic level to the next typical is 10% efficient (90% of

energy is lost),is diagramed as the pyramid of energy flow. then osprey eagle

are tertiary consumer and the shrimp are primary consumer, so to balance

mass of shrimp (1/0.1) / 0.1 = 100 kg 

c. heat from the poles back down towards the equator.

photosynthesis makes the glucose that is used in cellular respiration to make atp. the glucose is then turned back into carbon dioxide, which is used in photosynthesis. while water is broken down to form oxygen during photosynthesis, in cellular respiration oxygen is combined with hydrogen to form water.

the rocks are classified by the geological process they are formed by. the three main groups of rocks are igneous, metamorphic, and sedimentary. minerals are not they are classified under the chemical classes they are in. these groups include silicates, sulfates and carbonates.