Indicate whether each statement is true or false: 1. Water can move either direction across the wall of the small intestine; osmotic gradients across the epithelium determine the direction of its movement. True 2. Because of the osmotic gradient produced as nutrients are absorbed in the small intestine, nearly all water that enters by way of the oral cavity, stomach, or intestinal secretions is excreted. True 3. Potassium, calcium, chloride, magnesium and phosphate ions all move passively through the intestinal wall of the duodenum and jejunum following positively charged sodium ions. False

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.

Which statement best describes lactic acid fermentation? a. lactic acid fermentation is the first step of cellular respiration. o b. lactic acid fermentation is the final step of cellular respiration. re to berate c. in the absence of oxygen, cells release atp by breaking down lactose into glucose. e der lade res o d. in the absence of oxygen, cells release atp by breaking down glucose into lactate. ar

How can active reading strategies you? o a. they can you get into better physical shape. o b. they can you read fewer science articles. o c. they can you understand what you read. o d. they can you avoid reading altogether.