What is true of matter in ecosystems?
a. the primary productivity of an ecosystem does not depend on the availability of nutrients.
b. living things can recycle elements within an ecosystem as long as decomposers are present.
c. matter flows in a one-way direction with a 10% loss at each move up in trophic level.
d. elements continuously cycle between the physical environment and living organisms.

Which statement correctly describes a way that mutations increase the likelihood that a species will survive in a changing environment

Use this dichotomous key for insect identification to identify the insect shown. 1. a. insect has one pair of wings. order diptera b. insect has two pairs of wings. go to #2 2. a. front wings thicker in texture than hind wings go to #3. b. front and hind wings are same texture throughout. go to #4 3. a. front wings are short order dermaptera b. front wings cover entire abdomen order coleoptera 4. a. wings with scale on all parts of their area. order lepidoptera b. wings without scales go to #5. 5. a. hind wings smaller than front wings. order ephemeroptera b. front and hind wings nearly equal in size. order odonata the insect pictured is in the order diptera. ephemeroptera. coleoptera. odonata.

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