In general terms, normally a cell in your body crosses a checkpoint in the cell cycle when
a. it receives a "go-ahead" signal directly from your brain
b. concentrations of proteins in the cytoplasm reach the appropriate level
c. it receives a "go-ahead" signal from your external environment
d. concentrations of dna in the nucleus reach the appropriate level
e. a mutation in the dna occurs

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.

What is it called when part of a cell membrane closes around a molecule to allow the molecule to enter the cell? a. passive transport b.diffusion c. endocytosis d. exocytosisc. endocytosis

Plants contain the carbohydrates starch and cellulose.in the spring when stem growth is at its fastest rate, cellulose production rates are increased in some plants. in the months with less sunlight