Biology 104-Exam #2 Questions and
Answers
Phylum Angiosperms - Answer -flowering plants that are 250,000-300,000 in number
1. Monocots- 1 side leaf (Corn)
2. Dicots- 2 side leaves (Bean) - Answer -The 2 large classes of Angiosperms
Monocots - Answer --Have 1 cotyledon/side leaf
-The flower parts, such as the petals, are in 3s or in multiples of threes
-The leaf mostly has parallel venation (ex-grasses)
-Have no cambiums, therefore, they do NOT grow very tall
-Their vascular bundles are scattered
-The pollen (sperm) has only 1 aperture (whole, thin are in the wall of the pollen grain)
Dicots - Answer --Have 2 cotyledons
-The flower parts are in 4s, 5s, or in multiples of either
-The leaf veins are in some sort of network
-They have cambiums--both vascular and cork
-Usually grow taller and wider than monocots because of cambiums.
-The vascular bundles are in a ring.
-The pollen grain has 3 apertures
-Variety in shapes and sizes
Tissue Patterns of Angiosperm Stems - Answer -1. Herbaceous Dicot Stem
2. Woody Dicot Stem
3. Monocot Stem
Herbaceous Dicot Stem - Answer --Non woody, soft stem, usually only lives for one
season (an annual)
-Example: Alfalfa Grass
-Mostly primary tissue
-Vascular bundles are in rings-this separates the inner pith from the outer cortex
-Pith is in the center and is made of parenchyma
-Xylem is on the inside and carries water upward
-Phloem is on the outside and carries sap downward
-The vascular cambium is between xylem and phloem
Woody Dicot Stem - Answer --When it's young, the tissue looks like herbaceous
, -As it matures, Secondary Tissue (Xylem or Wood) is the most obvious difference
-Wood shows seasonal growth, this is the key!
-Springwood (early wood) shows larger vessels because sap going up.
-Summerwood (late wood) shows smaller vessels
-Together, spring/summer wood make an annual ring (one ring).
-Age can be determined by counting the rings.
-The easiest way to count rings is with a increment borer (tool).
As trees age, Parenchyma may grow into the conducting cells--forming TYLOSES,
which stops conduction.
-Resin, gum, and tannin accumulate--forming dark heartwood
-The lighter, still functioning, Xylem is Sapwood.
Bark - Answer -All the tissue outside the Cork Cambium--this includes Phloem carrying
the sap down.
Monocot Stem - Answer --These are soft
-The vascular bundle looks like a monkey head. Phloem is the forehead--it's always on
the OUTSIDE carrying sap down. Xylem is the nose and eyes, carrying water UP.
-There is NO cambium
-The cover is the epidermis
The vascular bundles are scattered.
1. Spiral- where the leaves alternate
2. Paired- leaves are oppositely arranged
3. Whorls- when there are 3 or more leaves - Answer -In Woody Stem Anatomy, what
are the 3 different leaf arrangements?
Node - Answer -The place where a leaf or branch arises
Internode - Answer -The space in between 2 nodes
Petiole - Answer -The stalk that a leaf has which attaches it to the stem
Axil - Answer -The angle between the Petiole and Stem
Axillary Bud - Answer --Located in the axil
-May become stems or flowers
-Each bud is protected by bud scales
Terminal Bud - Answer -A bud that is located at the end of each branch
Bud Scale Scar - Answer -A ring that marks the location of a terminal bud in season's
past
Stipules - Answer -Tiny paired leaves at the base of the petiole
Answers
Phylum Angiosperms - Answer -flowering plants that are 250,000-300,000 in number
1. Monocots- 1 side leaf (Corn)
2. Dicots- 2 side leaves (Bean) - Answer -The 2 large classes of Angiosperms
Monocots - Answer --Have 1 cotyledon/side leaf
-The flower parts, such as the petals, are in 3s or in multiples of threes
-The leaf mostly has parallel venation (ex-grasses)
-Have no cambiums, therefore, they do NOT grow very tall
-Their vascular bundles are scattered
-The pollen (sperm) has only 1 aperture (whole, thin are in the wall of the pollen grain)
Dicots - Answer --Have 2 cotyledons
-The flower parts are in 4s, 5s, or in multiples of either
-The leaf veins are in some sort of network
-They have cambiums--both vascular and cork
-Usually grow taller and wider than monocots because of cambiums.
-The vascular bundles are in a ring.
-The pollen grain has 3 apertures
-Variety in shapes and sizes
Tissue Patterns of Angiosperm Stems - Answer -1. Herbaceous Dicot Stem
2. Woody Dicot Stem
3. Monocot Stem
Herbaceous Dicot Stem - Answer --Non woody, soft stem, usually only lives for one
season (an annual)
-Example: Alfalfa Grass
-Mostly primary tissue
-Vascular bundles are in rings-this separates the inner pith from the outer cortex
-Pith is in the center and is made of parenchyma
-Xylem is on the inside and carries water upward
-Phloem is on the outside and carries sap downward
-The vascular cambium is between xylem and phloem
Woody Dicot Stem - Answer --When it's young, the tissue looks like herbaceous
, -As it matures, Secondary Tissue (Xylem or Wood) is the most obvious difference
-Wood shows seasonal growth, this is the key!
-Springwood (early wood) shows larger vessels because sap going up.
-Summerwood (late wood) shows smaller vessels
-Together, spring/summer wood make an annual ring (one ring).
-Age can be determined by counting the rings.
-The easiest way to count rings is with a increment borer (tool).
As trees age, Parenchyma may grow into the conducting cells--forming TYLOSES,
which stops conduction.
-Resin, gum, and tannin accumulate--forming dark heartwood
-The lighter, still functioning, Xylem is Sapwood.
Bark - Answer -All the tissue outside the Cork Cambium--this includes Phloem carrying
the sap down.
Monocot Stem - Answer --These are soft
-The vascular bundle looks like a monkey head. Phloem is the forehead--it's always on
the OUTSIDE carrying sap down. Xylem is the nose and eyes, carrying water UP.
-There is NO cambium
-The cover is the epidermis
The vascular bundles are scattered.
1. Spiral- where the leaves alternate
2. Paired- leaves are oppositely arranged
3. Whorls- when there are 3 or more leaves - Answer -In Woody Stem Anatomy, what
are the 3 different leaf arrangements?
Node - Answer -The place where a leaf or branch arises
Internode - Answer -The space in between 2 nodes
Petiole - Answer -The stalk that a leaf has which attaches it to the stem
Axil - Answer -The angle between the Petiole and Stem
Axillary Bud - Answer --Located in the axil
-May become stems or flowers
-Each bud is protected by bud scales
Terminal Bud - Answer -A bud that is located at the end of each branch
Bud Scale Scar - Answer -A ring that marks the location of a terminal bud in season's
past
Stipules - Answer -Tiny paired leaves at the base of the petiole
