Hort 1001 Lecture 10

Front 1

Angiosperms are composed of compressed stems with ___ nodes and ___ internodes.

Back 1

Angiosperms are composed of compressed stems with 4 nodes and 3 internodes.

Front 2

Peduncle

Back 2

Stalk of solitary flower or of the stalk of a cluster of flowers.

Front 3

Pedicel

Back 3

The stalks of individual flowers when flowers occur in clusters.

Front 4

Receptacle

Back 4

Region of tissue above the peduncle that gives rise to whorls/spirals of modified leaves.

Front 5

Sepals

Back 5

Leaf-like appendages and always lack sporangia. Usually green and photosynthetic.

Front 6

Calyx

Back 6

Together, sepals form the calyx (second ring of floral parts). Comprised of modified leaves called sepals. They are photosynthetic.

Front 7

Petals

Back 7

Leaf-like appendages lacking sporangia. Attract pollinators through bright colors and patterns. They can be fragrant and exude nectar.

Front 8

Corolla

Back 8

Together, petals form the corolla (first ring of floral parts).

Front 9

Stamens

Back 9

Make up the third whorl of appendages extending from the receptacle. They bear sporangia and produce spores. It consists of a stalk-like filament with a lobed anther at the top.

Front 10

Gametophyte (pollen grain)

Back 10

Form when microspores undergo a single mitotic cell division forming two cells within the original microspore.

Front 11

Carpel (pistil) and its regions

Back 11

Modified leaf containing internal protected megasporangia. Contains three regions: Stigma, Style and Ovary

Front 12

Ovary

Back 12

Forms base of carpel - hollow. Swollen region forming the base of the carpel.

Front 13

Style

Back 13

Elongated and supports the stigma. Length varies from species to species. Generally, plants pollinated by wind have long styles. Others have short styles or lack them. It elevates the stigma and serves as a pollen tube conduit.

Front 14

Stigma

Back 14

Found at terminal end of the carpel and traps pollen. Specialized for catching pollen and promoting germination of pollen plants of the same species.

Front 15

Tube Nucleus

Back 15

During germination of the pollen grain, the tube nucleus migrates into growing end of the tube and stays there.

Front 16

Generative Cell

Back 16

Becomes active and divides by mitosis to form two sperm cells that enter the pollen tube and descend following the tube nucleus.

Front 17

Locules

Back 17

Cavities of the ovary.

Front 18

Funiculus

Back 18

Ovules are attached to the ovary wall by this stalk like structure.

Front 19

Ovules

Back 19

Attached by funiculus to the tissue filling the center of the ovary. Found inside locules.

Front 20

Mother cell

Back 20

Surrounded by the megasporangium (nucellus) which is surrounded by integuments.

Front 21

Integuments

Back 21

Grow together enclosing the megasporangium and leaving only a small opening (micropyle) into the ovule.

Front 22

Receptacle

Back 22

Shorty chunk of stem where four different kinds of modified leaves can emerge from its nodes:

Front 23

Flowers have ___ nodes.

Back 23

4 nodes

Front 24

Rank the four nodes of receptacle from greatest to lowest (starting at the base of the receptacle).

Back 24

4th node: Calyx - base

3rd node: Corolla

2nd node: Androecium (men's house)

1st node: Gynoecium (women's house) - tip

Front 25

Why are the leaves/components of the receptacle modified?

Back 25

They are all modified leaves because they are specialized for sexual reproduction.

Front 26

Whorls

Back 26

The nodes where the modified leaves are attached. Called whorls because two or more of these leaves are attached radially around the node.

Front 27

Monocots have how many modified leaves attached at each node?

Back 27

3

Front 28

Dicots have how many modified leaves attached at each node?

Back 28

4-5

Front 29

Tepals

Back 29

Form when sepals and petals are showy and indistinguishable.

Front 30

Perianth

Back 30

Collective name for the calyx and corolla. Some flowers lack this (ex: corn) because they are wind pollinated and have no need to attract pollinators.

Front 31

Androecium

Back 31

Composed of modified leaves called stamens. MALE.

Front 32

Two components of stamens

Back 32

Filament

Anther

Front 33

Filament (long stalk)

Back 33

Male component of Androecium. Lifts the anther into a position where it can release pollen grains into/onto the pollinator. Has a plumbing function because it connects anther to the vascular system so it can receive water and nutrients.

Front 34

Anther (4 sacs with pollen grains)

Back 34

Male component of Androecium. Contains microsporangia and microspore mother cells where meiosis occurs. Meiosis leads to formation of male gametes (sperm) that will be packaged in a pollen grain.

Front 35

Gynoecium

Back 35

Female part composed of carpels.

Front 36

Pistil

Back 36

Carpels fused into compound carpel

Front 37

Three components of carpel

Back 37

Stigma: Tip on the end of structure.

Style: A supportive stalk.

Ovary: Swollen base.

Front 38

____ of mother cells leads to formation of female gametes (eggs).

Back 38

Meiosis of mother cells leads to formation of female gametes (eggs).

Front 39

Epigynous

Back 39

Flowers that have the other flower parts attached ABOVE the ovary.

Front 40

Perigynous

Back 40

Flowers that have an ovary that is surrounded by the fused bases of flower parts (calyx, corolla, androecium) that surrounds the ovary.

Front 41

Hypogynous

Back 41

Flowers that have the other flower parts attached BELOW the ovary.

Front 42

A flower that has a calyx, corolla, androecium AND gynoecium is a “__” flower.

Back 42

A flower that has a calyx, corolla, androecium AND gynoecium is a “complete” flower.

Front 43

Perfect, Bisexual or Hermaphroditic

Back 43

Flower with both androecium and gynoecium (male and female parts). Can self-pollinate.

Front 44

Cleistogamy

Back 44

In some species the anther matures and pollen is shed, and the stigma is receptive, BEFORE the flower even opens. It is common in self-pollinating agricultural crops.

Front 45

Why is self-pollination encouraged?

Back 45

Encouraged because it is tough for pollen from another flower to get to the stigma with a closed flower before pollen from the flower’s own anther gets there first.

Front 46

Protandry

Back 46

Pollen is shed before the stigma is receptive.

Front 47

Progyny

Back 47

Stigma is receptive prior to pollen shed.

Front 48

Self-Incompatibility

Back 48

Stigma and style recognize pollen produced by the same plant and thwart germination or pollen tube growth of these pollen (thereby avoiding self pollination).

Front 49

Incomplete flowers

Back 49

Only produce male or female parts.

Front 50

Staminate flowers

Back 50

Flowers with only androecium (male).

Front 51

Pistillate flowers

Back 51

Flowers with only gynoecium (female).

Front 52

In order to avoid self pollination, some plants have only ___ or ___ flowers.

Back 52

In order to avoid self pollination, some plants have only staminate or pistillate flowers.

Front 53

Dioecious

Back 53

Single-sex plant (always either staminate or pistillate)

Front 54

Monoecious

Back 54

Plant that contains both sexes, whether perfect or imperfect.

Front 55

True or False:Staminate plants divert all of their stored energy to their rhizomes and don’t have fruits (like pistillate plants do) into which energy is wasted. Extra energy stored in rhizomes results in greater shoot production. Ex: Asparagus.

Back 55

True