Chapter 21 Test*
What is the endosperm?
a food supply for the developing plant embryo
Water loss is not a problem for what group of plants?
aquatic plants
Root hairs anchor plants and help them absorb water and minerals by
increasing the root's surface area
Primary growth increases a plant's
length
The upper surfaces of leaves are used mainly for
light gathering
Which of these processes requires a plant to use energy?
loading sugars into the phloem
In what part of a leaf does most photosynthesis take place?
mesophyll
Insects captured by predatory plants provide the plant with
nitrogen
What does each tree ring represent?
one year of growth
The function of guard cells is to
open and close stomata
In the pressure-flow model, sugar is pumped into the phloem, and water flows into the phloem through
osmosis
Plant cells that have thin walls and store starch, oils, and water are
parenchyma cell
The blade of a leaf is connected to the stem by a thin stalk called a
petiole
The cohesion-tension theory proposes that water rises through he plants because of
physical properties of water
Division of a plants apical meristem cells produces
primary growth
Transpiration lowers the pressure in the leaf xylem, creating a vacuum that
pulls water upward
Which type of cell is found in the hard or gritty parts of fruits and vegetables?
sclerenchyma
Phloem tissue is made up mainly of
sieve tube elements and companion cells
A plant's ground tissue is found
throughout the plant
Function of cone of cone of cells at tip of root
to protect the growing part of the cell
Water vapor escapes from plants by the process of
transpiration
Cohesion is a result of hydrogen bonds that form between
water molecules
Water and dissolved minerals are carried from the roots to the rest of the plant by the
xylem
What makes sclerenchyma cells tough and durable
Their second cell wall hardened by lignin
How are parenchyma cells important in healing plant wounds?
They can regenerate throughout the plant's life
What is the function of fruit in flowering plants?
To help disperse seeds
Most leaves have a broad, flat part called a
blade
Where is the vascular cylinder of a root?
center of the root
What happens to the guard cells wen a plant is losing water from transpiration faster than it is gaining water
deflate and close the stomata
Dead parenchyma cells that make up bark form a type of
dermal tissue
Thin leaves such as spines and needles are adaptations to
dry climates
What does the cuticles protect the plant from?
drying out
What are the two basic forms of roots?
fibrous roots and taproots
A mature ovary of a flower is called
fruit
What does the pressure-flow model explain?
how sugars move through a plant