11. the highest level in the organizational hierarchy of the human body is the
a. atom.
b. organ system.
c. organism.
d. tissue.
12. the brain of the cell is called the
a. endoplasmic reticulum.
b. nucleus.
c. lysosome.
d. cytoplasm.
13. within the cell, the clean-up crew is the
a. endoplasmic reticulum.
b. nucleus.
c. lysosomes.
d. cytoplasm.
14. within the cell, a tubular network that is involved in protein synthesis and transport is the
a. endoplasmic reticulum.
b. nucleus.
c. lysosomes.
d. cytoplasm.

The health, management and conservation of biodiversity, is a challenge facing ecosystems worldwide. the major factors that affect the health and function of the great barrier reef are climate change and pollution. which question investigates the effects of a biotic factor on the reef ecosystem?

With the description of the different cell walls, membranes, and associated proteins set in the students' minds, you now need to introduce them to the idea that the cell wall can also act as a foundation to build things upon. bacterial appendages require a strong foundation that will offer the support needed to move and function in a dynamic world. for example, flagella are long, whiplike protein structures that are used by many gram-positive and gram-negative bacteria for locomotion. in order to function effectively, a flagellum must be firmly anchored to the cell wall. how will you be able to get across the idea that the peptidoglycan cell wall is strong enough to support such a mechanism? with a protein rod that passes through the cell wall and protein rings used to anchor it in the membranes, these basal bodies are the rudimentary biological motors that use atp power to spin the hook and the flagella attached to it. bacterial flagella have a biological motor that spins within the cell wall and is powered by atp. this allows the flagella to spin in a whiplike motion to propel the bacterium.

Most animal cells membranes have proteins that pump ions out of the cell and potassium ions into the cell