Unit 5: Seed Plants

Question 1

Vascular plants can be further divided into two groups:

Answer 1

Seedless plants

Seed plants

Question 2

Plants can be divided into two groups based on the presence of vascular tissue.

Answer 2

Non-vascular

Vascular

Question 3

There are two main groups of seed plants:

Answer 3

gymnosperms and angiosperms

Question 4

How is the development of seeds important from an evolutionary perspective?

Answer 4

seed in both groups replaces the function of the spore for dispersion of the species. Seeds provide a viable means for dispersal of offspring without the need for water. They are a far more efficient way of dispersal and allow plants to exist away from direct sources of water.

Question 5

• A seed is an ______________ surrounded by _____________________________.

Answer 5

• A seed is an _embryo__ surrounded by hard outer wall____.

Question 6

• Seed coat:

Answer 6

• Seed coat: protects the embryo from harsh environmental conditions.

Question 7

• Endosperm

Answer 7

a tissue that provides nourishment for the developing plant.

Question 8

• Seeds are diploid and result in the production of ________________________.

Answer 8

Sporophyte plant

Question 9

endosperm allow the seed to stay dormant. In other word

Answer 9

the seed doesn’t need to grow right away. If conditions are poor, the embryo can stay inside the seed and sustain life for long periods of time until conditions are right.

Question 10

• Seeds are diploid and result in the production of Sporophyte plant Roots have three primary functions:

Answer 10

First, roots gather water and minerals
o they draw nutrients and moisture in through their roots.
o They are the principle water-absorbing organs of a plant that grow underground

Question 11

Root hairs

Answer 11

greatly increase the absorbing surface of the root and have greater contact with soil particles

Question 12

Primary root

Answer 12

is the first root to emerge from the seed embryo and branches to for lateral roots.

Question 13

lateral roots

Answer 13

improve anchorage and prevents the plant from blowing away or falling over.

Question 14

some roots form as one large taproot that

Answer 14

taproot that swells and stores food and absorbs moisture. The food is stored in the form of carbohydrates (as starch). Some roots may become specialized below-ground storage organ. aka carrot

Question 15

Functions of the stem:

Answer 15

They provide support for the leaves, flowers and fruits of plants. They help the plant reach for light and transport water and minerals. People often confuse stems and shoots, but shoots are just fresh plant growths out of the ground. Basically, anything that is newly grown and sticks out of the ground is considered to be a shoot.

Question 16

Functions of Leaves:

Answer 16

Producing food and oxygen through photosynthesis
Balancing water loss
Regulating gas exchange
Transporting the products of photosynthesis (do you remember what the products are?!)
Absorbing the reactants of photosynthesis (carbon dioxide and water)

Question 17

cuticle:

Answer 17

cuticle: It is the waxy layer that prevents water loss

Question 18

The layer right below the cuticle is called the upper epidermis and it is a

Answer 18

protective layer of cells that produces the cuticle

Question 19

mesophyll:

Answer 19

Photosynthesis occurs in the different mesophyll cells

Question 20

vein:

Answer 20

consist of xylem and phloem. They play an essential role in transporting water to the chloroplasts in the mesophyll tissues

Question 21

The lower epidermis is also a protective layer of cells. In some plants, it also produces a waxy cuticle. Did you notice the tiny holes in the lower epidermis? Those are called

Answer 21

stomata and they allow carbon dioxide and oxygen to move in and out of the plant. The stomata are surrounded by a pair of sausage shaped cells called guard cells

Question 22

What is the function of the guard cells in stomata?

Answer 22

What is the function of the guard cells in stomata?
Guard cells are located in the leaf epidermis and pairs of guard cells surround and form stomatal pores, which regulate CO2 influx from the atmosphere into the leaves for photosynthetic carbon fixation. Stomatal guard cells also regulate water loss of plants via transpiration to the atmosphere.

Question 23

5. Why is it an advantage for a plant to have most of its stomata on the underside of the leaf?

Answer 23

stomata play an important role in photosynthesis as they allow the plant to absorb carbon dioxide from the environment. In exchange, stomata allow oxygen, which is a waste product of photosynthesis, to be released. In the process, water vapor is also lost as the internal parts of the leaves are exposed. To reduce exposure, stomata are found on the underside of the leaves. They are protected from the sun as excessive heat can increase the rate of water vapor leaving and thus wither the plant. Stomata also have guard cells around the epidermis that close when too much water is being lost

Question 24

2. What are the selective advantages of a seed over a spore?

Answer 24

they are a far more efficient way of dispersal and allow plants to exist away from direct sources of water

in terms of cellular complexity, seeds are superior because they’re multicellular, while spores are unicellular. A seed also has more facilities for plant survival than a spore

Question 25

Gymnosperms

Answer 25

were the first plants to have seeds. They are autotrophic, photosynthetic organisms that tend to conserve water. They have a vascular system (used to transport water and nutrients) that includes, roots, xylem and phloem.

Question 26

Gymnosperm adaptations that allow them to live on land include:

Answer 26

Alternation of generations (you should be a pro at explaining alternation of generations by now!).
Seeds that are resistant to drying out.
Seeds contain a fully formed embryo enclosed with food. This allows for greater survival and germination.
Woody growth supports the large plants and positions the needles (leaves) optimally for photosynthesis.
They have strong woody roots, allowing for optimal collection of water and nutrients.
They have needles instead of leaves. This is an advantage because there is less surface area for water loss and they are covered by a waxy cuticle.
Pollen from male cones is dispersed by the wind, so no water is needed for fertilization

Question 27

Gymnosperms are classified into four phyla:

Answer 27

Cycadophyta
Gingkophyta
Gnetophyta
Pinophyta

Question 28

Phylum Cycadophyta

Answer 28

They thrive in mild climates,
Large leaves
Cycads thrive in mild climates. Cycads are interesting because they bear large cones and are usually pollinated by beetles rather than wind- this is quite unusual! Cycads face possible extinctions and several species are protected

Question 29

Phylum Gingkophyta

Answer 29

There is one surviving species in this group and it is the Gingko biloba. These trees were originally only found in China but now can be found all around the world. They are recognized by their fan-shaped leaves. The interesting thing about G. biloba is that there are separate male and female plants. Typically, only male trees are planted because the seeds produced by the female plant have a pungent smell when they produce seeds (smells like rancid butter…yuck

unusual characteristic for ginkgoes is that the leaves fall from the tree at the end of each growing season. Trees that lose their leaves at the end of their growing season are called deciduous Most gymnosperms are evergreens and retain their leaves year-round.

Question 30

Phylum Gnetophyta

Answer 30

Gnetophytes are the closest relatives to modern angiosperms, which we will learn more about in the next chapter. They have broad leaves like angiosperms. The picture above shows Ephedra, which is found in dry areas of western USA and Mexico. It is the source of the drug ephedrine, which is used as a decongestant

Question 31

Phylum Pinophyta

Answer 31

• Most widely studied, also known as conifers.
• Important sources of: of wood, paper, ornamental plants and Christmas trees. Some examples include evergreen trees such as pines, hemlock ȾKÁ¸IȽĆ, spruces ₭ÍYÁL¸EŚEȽĆ , firs JSȺ¸IȽĆ and ₭ÍYÁL¸EŚEȽĆ , cedars ȾKÁ¸IȽĆ , sequoias, and yews ṮEṈ¸KIȽĆ .
• Examples: They are typically tall trees that usually bear scale-like or needle-like leaves.
• Bear scale-like or needle-like leaves
o How is this modification important for the survival of conifers? Give examples
o heir modified leaves reduce water evaporation because they have a thin shape and a thick cuticle
o
o Another advantage of having thin needles and a thick cuticle is when it snows in BC. We have gotten more snow than usual lately and that snow can easily slide off the needle-shaped leaves. This decreases the chances of branches breaking off and allows the leaves to catch that rare sunlight during snowy season

Question 32

Western Red Cedar- BC’s Official Tree
Thuja plicata
Uses by First Peoples:

Answer 32

The WSÁNEC Peoples’ used shredded XPȺ bark to make mats, hats, clothing, bedding, baskets and fish line. Logs were split into large, long planks and used to make big houses. XPȺ wood was made into dug-out canoes, totems, bent wood boxes, cradles, coffins, drum frames, masks, herring rakes and canoe bailers. Young branches would be twisted to make reef net frames, ropes. The roots made baskets, nets and mats.

The Western Red Cedars are aptly named the “trees of life” by the Northwest Coast Peoples, as the trees play a very important role in their culture. Both the bark and wood were important materials for constructing shelter, clothing, tools and transportation. The bark is durable and pliable, making it ideal to weave into skirts, hats and baskets. The wood of the tree is used for dug-out canoes, totem poles, long houses, tools, bentwood boxes and smoking fish. Various parts of the tree were also used for medicinal purposes, such as tuberculosis remedy and heart medicine. In addition to material use, cedar is prominent in spiritual culture and is often figured in mythology. Unlike modern forestry practices, Indigenous Peoples did not fell entire trees to harvest material. Instead they often used falled wood and peeled bark off in long vertical strips. The latter process has left many culturally modified trees, which remain as a part of the culture of the Northwest Coast Peoples.

Current industry also uses Western Red Cedar for many purposes. Due to its durability, lightness and resistance to decay, cedar is primarily used in home construction (roofing shingles, exterior finishings, decking and fencing). In addition, derivatives of cedar have also been found in cooking (to give flavour to smoked meats), insecticides, shoe polishes and medicine.
Reflecting the Western Red Cedar’s importance in the economy, heritage and culture of people living in British Columbia, it was named the provincial tree of BC.

Question 33

Western Red Cedar- BC’s Official Tree
Thuja plicata
Industry Uses: Current industry also

Answer 33

Industry Uses: Current industry also uses Western Red Cedar for many purposes. Due to its durability, lightness and resistance to decay, cedar is primarily used in home construction (roofing shingles, exterior finishings, decking and fencing). In addition, derivatives of cedar have also been found in cooking (to give flavour to smoked meats), insecticides, shoe polishes and medicine.
Reflecting the Western Red Cedar’s importance in the economy, heritage and culture of people living in British Columbia, it was named the provincial tree of BC.

Question 34

Male cones give rise to microspores, which produce pollen grains.

Answer 34

microspore

Question 35

megaspore

Answer 35

Female cones give rise to megaspores, which produce ovules.

Question 36

pollen tube

Answer 36

During pollination, pollen grains land on the female cone and a pollen tube develops from the pollen grain to initialize fertilization. It takes about a year for the sperm to reach the egg, which is only a few millimetres awa

Question 37

Pollination must occur for fertilization to take place. Zygotes develop into embryos inside seeds, from which the next sporophyte generation grows.

Answer 37

Pollination must occur for fertilization to take place. Zygotes develop into embryos inside seeds, from which the next sporophyte generation grows.

Question 38

Angiosperms are able to grow in a variety of habitats. They can grow as

Answer 38

trees, shrubs, herbs, bushes, and small flowering plants. What’s your favourite angiosperm? If I had to choose, I would say magnolia trees and peonies!

Question 39

Some common characteristics shared by all angiosperms are:

Answer 39

Their seeds are enclosed and protected inside a fruit of the flower.
All angiosperms have flowers at some stage in their life. The flowers serve as the reproductive organs for the plant- allow the exchange of genetic information.
Angiosperms, like all other plants, undergo an alternation of generations life cycle.
They have vascular tissue (xylem and phloem).
Angiosperms have small pollen grains that spread genetic information from flower to flower.
Angiosperms have smaller female reproductive parts than non-flowering plants. This allows them to produce seeds more quickly.

Question 40

cotyledon

Answer 40

A cotyledon is a leaf-like structure that the plant first produces when it germinates, sometimes called the first leaves. The very basic distinction between monocots and eudicots is the number of cotyledons it produces upon germination: one cotyledon makes a plant a monocot (mono- means one) and two cotyledons make a plant a eudicot (di- means two).

Question 41

All angiosperms belong to Phylum Magnoliophyta and are divided into two groups

Answer 41

s (monocots and eudicots).

Question 42

How do flowers create a symbiotic relationship with small animals?

Answer 42

The flower attracts insects or birds by its scent and colour and offers a sugary nectar for food. In exchange, the animal is sprinkled with pollen to carry to the next flower for fertilization. After it is fertilized, the flower will develop into a fruit which may be harvested or eaten by animals. The animals may ingest the fruit (with seeds) and migrate for miles before they, ahem, drop off the seeds with a bit of fertilizer.

Question 43

Anther

Answer 43

produces pollen (with sperm inside)

Question 44

Stamen- male parts Filament:

Answer 44

raises anther so pollen can be dispersed or picked up by an insect

Question 45

Stamen- male parts

Pollen

Answer 45

: vessel for dispersal of sperm

Question 46

Carpel (or pistil)- female parts

Stigma:

Answer 46

sticky to capture pollen

Question 47

Ovary:

Answer 47

becomes fruit to protect the seed

Question 48

Ovule:

Answer 48

eventually develops seeds

Question 49

• Petal:

Answer 49

• Petal: attracts pollinators

Question 50

• What is the function of this flesh?

Answer 50

The function of this flesh varies in different plants but it nourishes, protects and aids in the transport of seeds, to some extent.

Fruit is found on all angiosperm plants and are produced following the pollination of flowers. The main purpose of fruit is to protect seeds during development. They are also important for attracting birds and other animals to eat seeds. Plants use fruit to entice animals to eat their seeds because they can carry their seeds into new areas while the seeds are in their guts before releasing them with their feces

Question 51

As with gymnosperms, the diploid sporophyte stage is

Answer 51

dominant in angiosperms and the seed is responsible for the dispersal of species. We learned the components that make up a flower; the male parts are in the anther and the female parts are in the ovule.

Question 52

Angiosperm Reproduction (Flower) 	Male parts are in the \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_


Answer 52

Stamen
Anther- Pollen production

Filament

Question 53

Angiosperm Reproduction (flower) female parts are in the _________________

Answer 53

Carpel
Stigma
Style
Ovary

Question 54

pollination

Answer 54

Pollination is essential to the reproduction of flowering plants. It involves the transfer of pollen from one flower to another. Since plants are sessile (cannot move), they must rely on pollinators to transfer pollen for them. Different flowers have different pollinators. The pollinator depends on the characteristics of the flower.

Question 55

Moss are .

Answer 55

gametophyte