C. 37 - Reproduction in Flowering Plants

Question 1

Angiosperm pollen grains - #sperm and for what

Answer 1

Angiosperm pollen grains possess 2 sperm cells that are used during double fertilization in flowering plants

Question 2

How does pollination occur?

Answer 2

Angiosperm pollen may be transported by wind or animals, etc.

Question 3

What are some examples of organisms used to transport pollen?

Answer 3

Bees, butterflies, beetles, hummingbirds, bats

Question 4

How do plants take advantage of insects’ vision?

Answer 4

Insects can see the ultraviolet spectrum, so flower petals often show a sort of bullseye to attract the insect to feed/pollinate.
The striations are called “nectar guides”

Question 5

How does a flower such as a kind of orchid attract insects?

Answer 5

It has a structure that resembles a female bee. When the male bee tries to have sex with it, he inadvertently pollinates the flower.

Question 6

If a single gene change causes the pollinators to shift from bees to hummingbirds, what has changed

Answer 6

Color (in one example)- attracts different species

Question 7

Describe the process of pollination

Answer 7

1. Pollen grain lands on stigma (sticky part of pistil)
2. Pollen tube grows
3. Two (2) sperm move down the pollen tube to the ovule
4. Double fertilization occurs
   a. Zygote
   b. Triploid endosperm (3n)

Question 8

What are the 6 different types of fruit? Give examples.

Answer 8

1. Berry - simple fleshy fruit with a thin wall
   a. tomato
2. Legume - pea pod
   a. green bean
3. Nut
   a. oak-acorn
4. Aggregate fruit - develops from a single flower
   a. blackberry
5. Multiple fruit - develops from a group of flowers
   a. mulberry
6. Accessory fruit
   a. apple, pear

Question 9

What are the four types of seed dispersal?

Answer 9

1. Wind
2. “Hitchhikers”
   a. bird feathers, mammal fur, human clothing
3. Burial
   a. Small animals (ants), white material (food source for ants) – they bury them underground
4. Explosive dehiscence

Question 10

Give examples of each type of seed dispersal.

Answer 10

1. Wind - milkweed seeds
2. Hitchhiker - burs
3. Burial - bloodroot seeds
4. Explosive - bittercress
5. Shit out - blackberry
   a. Some seeds need to go through the highly acidic environment of the digestive tract in order to germinate. Some seed coatings act as laxatives to ensure their timely dispersal.

Question 11

Why do seeds disperse?

Answer 11

To avoid competition with parent plants and spread out the population

Question 12

What is imbition?

Answer 12

Dry seeds must “imbibe” (take in) water before germinating.

Question 13

How do eudicots and monocots protect young plants?

Answer 13

Eudicot: hook - helps protect embryonic leaves

Monocot - coleoptile

Question 14

Name and describe the 5 modified stems used in asexual reproduction of flowering plants.

Answer 14

Rhizome - a horizontal underground stem
Tuber - A rhizome with enlarged ends (potato)
Bulb - Modified underground bud with fleshy storage leaves
Corm - A very short, erect underground stem that resembles a bulb
Stolon (Runners) - horizontal above-ground stems

Question 15

What are two more structures used in asexual reproduction?

Answer 15

Plantlets (small plants) - detach and grow into individual plants
Suckers - above-ground shoots from roots
a. Advantage: if a stem dies, the plant can keep surviving
b. Chestnut