Module 15 (vocabulary is on Biology ipad app)

Question 0

A biologist studies two plants. The flowers of the first plant open each morning and close each night. The second plant’s flowers stay open all of the time. However, if the plant is placed so that one of its sides is in the shade and the other is in the sunlight, the plant will eventually grow so that all of its leaves point towards the sunlight. Which plant is using nastic movement and which is using phototropism?

Answer 0

The first plant is using nastic movements and the second is using phototropism.

Question 1

Name the four processes for which plants require water. Which of these processes can be neglected for a short amount of time?

Answer 1

A plant uses water for photosynthesis, turgor pressure, hydrolysis, and transport; turgor pressure can be ignored for a short time.

Question 2

Briefly describe the cohesion-tension theory of water transport in plants.

Answer 2

The cohesion-tension theory states that when water evaporates through the stomata in a plant’s leaves, a deficit of water is created. This causes the water molecules just below those that evaporated to move up and take their place. Since water molecules like to stay together, however, the water molecules just below the ones that moved up also move up, in order to stay close. This causes a chain reaction, eventually causing water from the roots to move up into other parts of the plant.

Question 3

Do xylem cells need to be alive in order for xylem to do their job? Why or why not?

Answer 3

Xylem cells need not be alive for xylem to do their job; they need not play an active role in transport

Question 4

Do phloem cells need to be alive in order for xylem to do their job? Why or why not?

Answer 4

Phloem cells must be alive in order for the phloem to do their job, because the phloem cells take an active part in translocation.

Question 5

What substances do xylem contain? What substances do phloem contain?

Answer 5

Xylem contain water and dissolved materials, while phloem contain sugar and organic substances.

Question 6

Do insectivorous plants really eat insects? Why or why not?

Answer 6

Insectivorous plants do not really eat insects. They decompose the insects and use their raw materials for biosynthesis.

Question 7

From a genetic point of view, what is the difference between vegetative reproduction and sexual reproduction in plants?

Answer 7

Vegetative reproduction leads to offspring with genetic codes which are identical the parent. Sexual reproduction leads to offspring with genetic codes which are similar to, but not identical to, the parents’ genetic codes.

Question 8

A gardener says that one limb of his crabapple tree now produces normal-sized apples. What must the gardener have done to make this happen.

Answer 8

The gardener must have grafted limbs from a tree that produces normal-sized apples to his crabapple tree.

Question 9

What is the male reproductive organ of a flower? What is the female reproductive organ?

Answer 9

The stamen is the male reproductive organ, and the carpel is the female reproductive organ.

Question 10

Why are the pollen grains and embryo sacs of flowers sometimes considered the gametophyte generation in an alternation of generations life cycle?

Answer 10

Both structures are multicellular, and they both reproduce using gametes.

Question 11

What two types of cells are found in a pollen grain?

Answer 11

sperm cell; tube nuclues

Question 12

Typically, how many cells are in an embryo sac? How many of them get fertiziled?

Answer 12

Typically, there are seven cells in an embryo sac. Two of these cells get fertizied.

Question 13

See problem #15 on page 494

Answer 13

a. stigma
b. style
c. ovary
d. ovule
e. sepal
f. anther
g. filament
h. petal
i. receptacle
j. pedicel

Question 14

See problem #16 on page 494

Answer 14

carpel

Question 15

See problem #17 on page 494

Answer 15

stamen

Question 16

What is the difference between pollination and fertilization?

Answer 16

Pollination is simply the transfer of pollen from an anther to a stigma, while fertilization is the act of the sperms fusing with the egg and the large central nucleus in the embryo sac.

Question 17

How many sperm cells are used in plant fertilization?

Answer 17

2

Question 18

Where does the endosperm come from? What is its purpose?

Answer 18

comes from the fertilization of the large, two-nucleus cell that is at the center of the embryo sac; it provides nutrition for the developing embryo.

Question 19

The cotyledon or cotyledons help provide food for the plant before and often after germination. How do cotyledons accomplish each task?

Answer 19

Cotyledons either absorb the endosperm or aid in the transfer of nutrients from the endosperm to the embryo. After germination, they often perform the first photosynthesis in the plant.

Question 20

Name the three basic parts of the plant embryo and what each gives rise to in germination.

Answer 20

The three basic parts are the radicle, the hypocotyl, and the epicotyl. The radicle becomes the root, the hypocotyl the stem, and the epicotyl gives rise to the first true leaves of the plant.

Question 21

What the purpose of a fruit?

Answer 21

it allows for the dispersal of seeds to places away from the parent

Question 22

Name at least three ways in which pollen is transferred from the stamens of one flower to the carpel of another.

Answer 22

wind, bees, beetles, birds, moths, or butterflies

Question 23

Why are cotyledons sometimes called “seed leaves?”

Answer 23

They form leaf-like structures if they end up rising above ground with the seedling.