The sodium-potassium pump is a membrane protein that pumps sodium out of the cell and brings potassium in. It does this against the concentration gradients; in other words, it pushes both molecules from areas of low concentration to areas of already high concentration. What type of transport is this? a. passive transport, which requires energy
b. passive transport, which does not require energy
c. active transport, which requires energy
d. active transport, which does not require energy

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.

Climate warming trends allow plant and insect species to inhabit larger ranges. select the best answer from the choices provided

Explain how paleontologists use trilobite fossils as index fossils for various geologic time periods.