Modules 7+8 Inflorescence and Fruits Flashcards
What is a zygomorphic flower? Give 1 ex.
Flowers are bilaterally symmetrical (mirror image) ex. orchid, violets, snapdragon
What is an actinomorphic flower? Give 1 ex.
Flowers that are radially symmetrical. They can be divided into two equal parts or mirror images by multiple lines or planes of symmetry. ex. ranunculus, scilla, lily, calendula
What type of flower contains both stamens and pistils?
Perfect flower
Describe an imperfect flower and give and example.
Imperfect flowers contain stamens or pistils but not both. For ex. begonia has some flowers with stamens and others with pistils.
A complete flower must have all 4 of these:
- sepals
-petals
-stamens
-pistils
If a flower had sepals, petals, and stamens what type of flower would it be?
Incomplete flower
_____________ means that the male and female flowers are found on the same plant.
Monoecious (one household)
Another term for monoecious is:
unisexual
_____________ means that the male and female flowers are found on separate plants.
Dioecious (two households)
What is the definition of pollination?
The transfer of pollen from the anther to the stigma.
Give 3 examples of a pollination vector:
- wind
- water
- animal
What vector is used to pollinate most grasses?
Wind
Give two examples of adaptations that grasses have to increase chances of pollination?
Grass flowers lack petals, sepals, pigmentation and scent and use most of their energy to produce abundant pollen with long feathery stigmas. (No wonder ppl are allergic!)
Grass plant populations found in large numbers, therefore can exchange lots of pollen.
Flowers found high on the plant where they have better exposure to wind.
What is an example of a mutualistic relationship in pollination?
Animal pollination – > animal gets nutrition, plant gets pollinated
bees use products from pollen and nectar to feed young and queen
What are three ways flowers attract animal pollinators?
- scent
- colour
- shape
What type of animal would a long, red, tubular flower be likely to attract?
Hummingbird
A disk like flower would be most likely to attract:
butterflies
How much of our food supply depends on bees?
About 1/3
Where do bees collect pollen? Describe.
Bees collect pollen in scopae (sing. scopa). Scopa is a group of dense electrostatic hairs often found on the back legs or the bottom of the abdomen.
These specialized scopae carry both pollen and nectar and are found on honeybees and bumblebees:
Pollen baskets
What are the three scenarios in which self-pollination might take place?
- anther and stigma are on the same flower
- anther and stigma are on different flowers of
the same plant - anther and stigma are on different flowers of
different plants of the same clone
Define cross-pollination
Anther and stigma are on different flowers of different plants that are not of the same clone.
Would it be considered cross-pollination or self-pollination if different plants of the same clone pollinated each other?
Self-pollination
What is the definition of sexual reproduction?
A new organism is produced by combining the genetic material of 2 different cells.
What are the advantages of self-pollination?
- ” purity of the race is maintained” [:/]
- less wastage of pollen grains
- less dependence on external factors for
pollination
What are the disadvantages of self-pollination?
- cannot produce new varieties
- the vigor of the species may be reduced
- offspring may be more susceptible to disease
What are the advantages of cross-pollination? (4)
the introduction of new genes is beneficial to the
species
* new varieties are produced
* resulting seeds and plants have improved vigor and
vitality
* new plants tend to have improved resistance to
disease
What are the disadvantages of cross-pollination? (5)
more wastage of pollen grains
* pollination may not occur due to distance between
plants
* possible introduction of detrimental characteristics
* greater dependence on external factors for
pollination
* greater energy spent by some plants to produce
flowers to attract animal pollinators
What is the pollen grain?
Produced on the anther, a pollen grain contains 2 cells.
What are the purposes of the 2 cells in the pollen grain?
- To produce the pollen tube once landed on the stigma by burrowing into the style
- Divides in 2 to form 2 haploid sperm cells that travel down the pollen tube.
What is the difference between the ovary and ovule?
Ovary holds the ovules. Ovules = seed when mature, ovary = fruit when mature (not always tho)
What is it called when the sperm cell fuses with the egg cell in the ovule?
Zygote
What is it called the sperm cell fuses with the central nuclei?
Endosperm
What provides food to the zygote in angiosperms?
Endosperm
When the zygote divides what does it become?
Embryo
What is the scientific name for the tissue surrounding the seed (mature ovary) called?
Pericarp
Draw and label the three tissues that make up the pericarp.
Endocarp, mesocarp, exocarp
What is the production of fruit without fertilization with NO seeds called? Give an example.
Parthenocarpy. Ex. Banana, navel orange, pineapples.
What is production of fruits without fertilization WITH seeds? Give an ex.
Apomixis. Ex. apple, reproduced through grafting.
How do seeds disperse when mature?
The seeds may be dispersed when the fruit rots
or cracks open or when they are transported by
wind, water or animals.
What is a fruit? How does it come to be?
Fruits are mature ovaries.
Following fertilization ovules grow and develop into seeds. The ovary enclosing the ovules enlarges (this is the fruit).
What are the 4 main functions of a fruit?
- Protect the seeds
- prevent seeds from dehydrating
- disperse the seeds
- provide food for the seedling
Describe a simple fruit. What category are simple fruits divided into?
Simple fruit is from a flower with one ovary. Subdivided into: fleshy or dry fruits.
Describe a compound fruit. What categories are compound fruits divided into?
Formed from a flower with several ovaries or from multiple flowers. Subdivided into: aggregate or multiple fruits.
What type of simple fruit is a mango?
Fleshy fruit
Why are fleshy fruits juicy?
To prevent dehydration of the seeds.
How might a simple fleshy fruit’s seeds be dispersed?
An animal eats the fruit and ingests the seeds, the animal walks away and poops elsewhere and the seeds come out in the feces intact.
What are the 5 categories of simple fleshy fruits?
- Berries
- Hesperidiums
- Pepos
- Drupes
- Pomes
Which type of simple fleshy fruits have a pericarp that is completely fleshy? Ex. Tomato, eggplant
Berries
Describe a hesperidium.
Leathery exocarp and mesocarp.
Juicy and partitioned endocarp.
Ex, citrus fruits
Which type of simple fleshy fruits have a thick, hard rind and fleshy matrix on the inside?
Pepos! Melons, squash
Which simple fleshy fruit has a stony endocarp, fleshy mesocarp, and thin exocarp?
Drupes. Cherries, peaches, plums
Describe a pome and give an example.
Pomes consist of the pericarp and the fleshy bases of the perianth. Ex. apples, pears.
The bulk of what we’re eating when we eat an apple or pear is:
the hypanthium
Dry fruits are subdivided into which two types?
Indehiscent and dehiscent fruits
What does in/dehiscent refer to?
Whether or not the fruit splits open when it matures.
How many seeds do indehiscent fruits usually contain?
1 or 2
What are the 4 subdivisions of indehiscent fruits?
- achenes
- samaras
- nuts
- schizocarps
Which indehiscent fruit is one-seeded and attached to the fruit at one location? Ex. sunflower or buckwheat.
Achene
What is a samara? Give an example
Indehiscent, simple dry fruit. A (single) winglike appendage that develops from the pericarp. Ex. maples, ashes, elms.
These are one-seeded simple dry fruits with very hard pericarps.
Nuts
Describe what type of simple dry fruit parsley, carrot, and dill produce and the origin of the prefix.
An indehiscent fruit that separates when ripened into two or more one-seeded mericarps. Schizo means “split”
What are the 4 subdivisions of dehiscent fruits?
- Legumes
- Follicles
- Capsules
- Siliques
This dehiscent fruit consists of one carpel and splits open along two lines or sutures when ripened:
Legume ex. beans, peas, honeylocust
Describe what type of fruit a follicle is and how to identify it.
Dehiscent simple dry fruit. Follicles consists of one carpel and splits open along one line or suture when ripened. Examples include the fruits of milkweed and spireas
What type of fruit is a poppy or okra? Describe this group.
Capsule, dehiscent, simple dry fruit.
Contains more than one carpel and splits open along more than two sutures when ripened.
Which dehiscent simple dry fruit consists of two carpels that separate when ripened. A thin partition or septum, is found in between the two carpels. Which family do these fruits belong to?
Silique. Mustard, brassicaceae (formerly cruciferae).
