Question

1. Increasing the gravel content of soil will:

   	a.	Decrease the average particle size of soil
   	b.	Increase the capacity of soil to hold water
   	c.	Decrease oxygen availability
   	d.	Decrease availability of magnesium (Mg2+) and calcium (Ca2+) for absorption by root hairs
   	e.	None of the above are true

2. Which of the following statements about active exclusion of sodium are true?

   	a.	It is dependent on a proton gradient and ATP
   	b.	It requires antiporters that exchange H+ for Na+
   	c.	It prevents accumulation of sodium in plant cells
   	d.	It allows for greater uptake of sodium into plant cells
   	e.	All of the above statements are true EXCEPT D

3. Double fertilization refers to:

   	a.	Cross-pollination by two distinct mechanisms (e.g. wind and bees)
   	b.	The formation of male (n) and female (n) gametes
   	c.	The development of a fruit in an angiosperm
   	d.	The process of embryogenesis and seed maturation
   	e.	The formation of a zygote (2n) and primary endosperm nucleus (3n)

Answer 1

1-E- NONE OF THE ABOVE ARE TRUE

Soils filled with gravel and rocks tend to drain faster but are not rich in nutrients. This creates a harsh growing environment in which many plants cannot survive. ... A third option for gardeners dealing with gravel-filled soil is choosing plants that tolerate rocky ground

2- E- ALL OF ABOVE STATEMENTS ARE TRUE EXCEPT D

sodium ions are not permeable to cell membrane, thus they require system to export . thus they depend on proton gradient to go ions into cell and doesnot allow much accumulation

3- E- FORMATION OF ZYGOTE(2N) AND PRIMARY ENDOSPERM NUCLEUS (3N)

Double fertilization is a major characteristic of flowering plants. In this process, two male gametes fuse with one female gamete wherein one male gamete fertilizes the egg to form a zygote, whereas the other fuses with two polar nuclei to form an endosperm