According to National U

question 104

Multiple Choice

According to national U.S.studies, in 1978 nearly __________ of children ages 5-10 had dangerously elevated levels of lead in their blood, which can cause brain damage; by 2001, the rate had fallen to __________.

• A)30%; 1%
• B)40%; 5%
• C)50%; 10%
• D)60%; 15%

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Definitions:

Axillary Bud

Bud located in the axil of a leaf.

Bud Scale

A small protective covering over a bud that shields it from the elements and pathogens.

Casparian Strip

Layer of impermeable lignin and suberin bordering four sides of root endodermal cells; prevents water and solute transport between adjacent cells.

Vascular Cylinder

In eudicots, the tissues in the middle of a root, consisting of the pericycle and vascular tissues.