Chpt. 1 Tree Biology Flashcards
Specialized zones where new cells arise from existing cells
meristems
Following cell division, the process that plant cells use to change their structure and assume a variety of different functions
differentiation
Plant cells with similar structure and function are arranged into _____, like bark or wood.
tissues
Plant tissues are organized into organs. There are 5 organs. Name them.
Leaves, stems, roots, flowers & fruit
What are the two basic types of meristems?
Primary & secondary
What type of growth occurs from primary (apical) meristems?
(Primary growth) Elongation of shoots and roots
What type of growth occurs from secondary (lateral) meristems?
Increase in diameter, produces wood, palms lack this
What structures protect the apical meristem in the shoots? The roots?
Buds protect shoots; root caps protect roots
What are the two secondary (lateral) meristems produced by plants?
Cambium & cork cambium
Cambium is a thin sheath of dividing cells that produces the ________ system of the plant.
Vascular
The cambium produces two types of tissues: ________ on the inside, and ________ on the outside.
Xylem (inside); phloem (outside)
The cork cambium produces _______.
Bark = periderm
Plant cells have cell walls, animal cells do not. T or F?
True
Name two components of plant cell walls that provide support to the cell.
Cellulose (most common organic compound on earth) & lignin (rigidity to help trees grow tall)
The xylem (wood) in a tree has 4 functions. Name them.
- conduction of water & minerals;
- support weight of tree;
- store carbs;
- defend against spread of disease/decay
Xylem is composed of living cells called _______ & dead cells called ________ (they compose most of the volume of a mature tree).
Symplasm (alive); apoplasm (dead)
The xylem of soft woods & hard woods both contain three types of cells. Name them.
Hardwoods also have an additional group of cells called ________.
- tracheids (dead cells that conduct water & provide support)
- fibers (provide strength)
- parenchyma cells (living cells that store carbs, defend against disease/decay, cut across the grain, more abundant in hardwoods)
Hardwoods also have VESSELS (dead hollow cells that conduct water)
Hardwood trees that form wide vessels early in the growing season and narrower vessels later in the season are called _______.
Ring porous (elm, oak, ash trees)
Hardwood trees that form uniform vessels throughout the growing season are called ________.
Diffuse porous (maple, planetree, poplar)
Conifers (soft woods) do not have vessels in their xylem and are called _______ for this reason.
Nonporous
Growth rings in a tree are the result of ________ produced during a growing season.
Xylem
As a grow season progresses, the xylem cells in a tree _______ in size.
Decrease, earlywood will have larger cells than latewood.
Xylem that conducts water and has parenchyma cells is called _______.
Sapwood
Dead xylem cells inside the tree that do not conduct water are called ________.
Heartwood
Phloem tissue in the cambium moves __________ in the tree.
Carbohydrates (produced in the leaves)
Phloem is composed of live cells.
In conifers, that are called ________.
In hardwoods, there are _________ & __________.
Sieve cells (conifers); Sieve tube elements & companion cells (hardwoods)
Old xylem becomes the “wood” of a tree. What happens to old phloem?
It is reabsorbed and the cell walls are incorporated into the bark.
Plants transport water and nutrients longitudinally (axial transport, up and down) through xylem & phloem. How does it transport nutrients radially (across the plant)?
RAYS are parenchyma cells that run across the grain from the phloem to the sapwood. They transport nutrients, store carbs, & restrict decay.
The waxy, corky bark of a tree helps it moderate temperature, prevent injury and reduce water evaporation. How does gas exchange occur in the bark?
LENTICELS are small openings in the bark that allow for gas exchange.
Buds located at the end of a stem or branch are called _______ buds, and are usually the most active and dominant on the stem/branch.
Apical/terminal buds
Buds located along a stem or branch are called _________, and are usually dormant.
Lateral/axillary buds
Buds that are produced in areas where meristems are not normally found.
Adventitious buds
The enlarged area on a stem/branch where leaves or buds arise is called the ________.
Node
What is the area between nodes on a stem called?
Internode
Branches of a tree are strongly attached to the trunk (bark/wood) __________ the branch, and weakly attached to the trunk _________ the branch.
Beneath (strongly); above (weakly)
The bulge around the base of the stem/branch is called the ________ __________.
Branch collar
Between the branch and trunk in the crotch is formed a _______ ________ _________ because the branch and trunk are expanding against each other.
Branch bark ridge
Leaves produce food (carbs) for trees via cells called ____________ that contain a green pigment called ____________.
Chloroplasts; chlorophyll
Sunlight in chloroplasts is converted to chemical energy (carbs) through what reaction?
Photosynthesis
The loss of water through the leaves that helps to cool the plant and pull water up through the xylem is referred to as what?
Transpiration
What is the name for the waxy outer coating on a leaf that prevents desiccation?
Cuticle
Small openings on a leaf that regulate water loss and gas exchange are called _________.
Stomata
These cells act to open or close the stomata on a leaf.
Guard cells
Deciduous trees shed their leaves how often?
Periodically, typically every year
What is the name for trees that do not shed their leaves periodically?
Evergreen
Deciduous trees form this at the leaf stalk (petiole) to allow leaf drop and protect the area where the leave will drop from disease or desiccation.
Abscission zone
Fall foliage color change is the result of what?
Accumulation of carbs, reduction of chlorophyll, allows other pigments to be visible.
Red and purple pigments in leaves are called __________. Yellow, orange and red pigments are called ____________.
Anthocyanins; carotenoids
What are the four primary functions of a plant’s roots?
- anchorage
- storage
- absorption
- conduction
Larger roots tend to provide anchorage, storage and conduction. Smaller roots that aid in absorption are called ________.
Absorbing roots
Roots grow where there are _______ & _______; usually the top _______” in the soil.
moisture, oxygen, 12”
Sinker roots grown off the main lateral (horizontal) roots in which direction?
Downward, vertically (increase anchorage and nutrient/moisture uptake)
True or false: Tap roots are commonly found in mature trees.
False: It is usually choked out by other roots as tree matures
What is the name of the area where the roots meet the trunk of a tree?
Root crown
True or False: The radius of the roots of a tree grown in the open can extend to 2-3 times the radius of the tree crown.
True; roots will grow where oxygen, moisture and space are available
What is the name for the symbiotic (mutually helpful) relationship that fungi and roots have?
Mycorrhizae (fungus covered roots); fungus gets food from the roots, roots get water & minerals from the fungus
What is the name for the carbs produced through photosynthesis?
Photosynthate (many of this is stored by the plant as starch)
What is the name of the process both plants and animals use to convert food to energy?
Respiration
Carbon dioxide is required for photosynthesis. What gas is required for respiration?
Oxygen
Transpiration is the natural loss of water vapor in a plant. Why would someone apply an anti-transpirant spray to a plant?
Reduce water loss due to drought or transplant by blocking stomal pores; drawbacks are they reduce cooling of leaves, uptake of CO2, and photosynthesis
The process of water moving into and out of roots from the soil is called __________.
Osmosis (waters moves from higher concentration to lower concentration; salt water “draws” fresh water out of plant roots)
What is a gymnosperm? What is an angiosperm?
Gymnosperm (naked seed, conifers); angiosperm (seed in ovary; monocotyledons/grasses & dicotyledons/woody trees & shrubs, etc.)
Phloem moves carbs from the source to the sink. What does this mean?
It moves carbs from where they are manufactured (source) to where they are needed (sink).
Axial transport moves water and nutrients in which direction? What about radial transport?
Axial =longitudinal (up and down)
Radial = horizontal (across)
What are plant growth regulators/ plant hormones?
Compounds that act in small quantities to regulate plant growth and development.
Auxin is a growth regulator. Where in the plant is it produced? What does auxin affect?
Produced in shoot tips. Affects root development (used in products for cuttings, or herbicides) & tropisms (direction of growth)
What is geotropism? Phototropism?
Direction of growth in response to gravity (geo) or light (photo)
Cytokinin is a growth regulator. Where in the plant is it produced? What does it affect?
Produced in roots. Affects shoot initiation & growth.
When new lateral shoots outgrow the original terminal shoot year after year, what shape tree is the result?
Round-headed, DECURRENT
Trees with strong apical dominance have a strong central leader (trunk that runs up height/center of tree). This type of growth is called what?
EXCURRENT, conifers
What is the name of the process trees use to limit the spread of decay or discoloration?
Compartmentalization
What is CODIT? What are the 4 walls created as part of CODIT?
Compartmentalization Of Decay In Trees:
Wall 1 - resists vertical spread; blocks xylem
Wall 2 - resists inward spread; chemicals in latewood
Wall 3 - inhibits lateral spread; activates ray cells
Wall 4 - inhibits outward spread; growth of new wood tissue
Many tropical trees have buttress roots. What do they do?
Roots at truck base that help support tree and distribute mechanical stress
Some tropical trees produce roots from stems and branches above ground (aerial roots). Why?
To aid in support, gas exchange & propagation (creating new clone plants from the parent plant)
Palms are ________, so they have more in common with grasses than hardwood trees.
monocots
Instead of a cambium layer or growth rings, palms have ______ ______ of phloem and xylem bundled together.
Vascular bundles (xylem and phloem surrounded by fibrous tissue)
Because palms have no cambium layer, there is no secondary growth results in girth. Also, how does this affect any damage to the stem of the palm?
Wounds on stems cannot be healed.
What is an inflorescence?
A flower
Roots of a palm are generally adventitious, and develop from an area of the palm called the _______. Most roots are close to the stem and soil surface (top 12-18”), this is called a ________ _________.
Root initiation zone; root mat
