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Notes - Seed Bearing – Gymnosperms and Angiosperms

Part 1 – Gymnosperms

- Sub phylum _______________ is Latin for “naked seed”. This is fitting as the seeds are exposed

to the environment at maturity. Gymnosperms are ________, ___________, and __________

are thought to be first plant to not need water for their life cycle.

- Conifers – ________ __________ - are the most successful of this subphylum with over ____

types spread over most of the northern hemisphere. They are extremely drought resistant with

needle like leaves with a thick ________. Ex. –

- Cycads look like palm trees with seeds on cones. They exist in tropical and subtropical regions.

- ____________ are the oldest but only one species remains, Ginko biloba as the Chinese have

grown them in their gardens for millennia. A very _____________ _____________ tree.

- Gymnosperms are photosynthetic in gathering energy. ___________ (leaves) last 2-14 years,

contain a thick, _________ __________, and contain small pits on the underside. At the

bottom of these pits are specialised openings, called stomata, which allow the exchange of

______________ made from photosynthesis with __________ ____________ from the air.

- Chloroplasts in the needles change sunlight into sugars (_________). The sugars are transported

throughout the plant by sieve cells in the ___________. Water and minerals are transported by

hollow, dead tracheid cells or _______ which transport horizontally across the stems. Tracheid

cells are what form the _____________ of a tree and thus form the “growth rings”. Together,

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xylem and phloem make up the vascular cylinder for transport. _____________ is unspecialised

cells that adds more _________ on its inside and more ________ on its outside. Cambium is

composed of meristem tissue. Meristem tissues are cells capable of ________ throughout life

of the plant. They are also found in root tips as roots keep growing and spreading into soil. The

_______ forms the outer protective covering for trees called bark. The plant also has ______

__________. These are specialised cells that produce resin, which is a mixture of

_____________ and rosin. This inhibits infection from insects and _______.

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- The sporophyte is the dominant form we recognise as a tree. As all tracheophytes they have true

roots, stems, leaves and vascular tissue. Reproduction occurs through production of two

different cone types. Male cones (pollen cones) are smaller and produce pollen (male

gametophyte) to blow to the female cone, undergo meiosis to produce sperm, and fertilize the

egg (15 months long!). Female cones (seed cones) produce ovules, areas that house the female

gametophyte. Once the egg is fertilised by sperm from the pollen grain, the zygote develops into

an embryo. The embryo is stored food and a protective coat which we now call a seed.

- ______________ from humans, clear cut logging, and lack of forest fires have ______ conifers.

Sulphur dioxide from fossil fuel burning enters through stomata and causes stoma __________.

This has lead to increased penetration from disease and increased water loss. As well,

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__________ have been causing a reduced leaf size (less photosynthetic area). Forest fire

decrease has increased old, weak trees, that help feed insect infestations and _____________

cone release of seeds.

Part 2 – ______________

General Characteristics

- Subphylum Angiosperma is Latin for “_______________”. Angiosperms are what we know as

flowering plants. They are considered the _________ and most advanced of the plant kingdom.

- Angiosperms – flowering plants – all angiosperms are divided into one of ____ groups, based on

the seed type; monocotyledons (monocots) or _______________ (dicots). Both types of seeds

have an embryo, epicotyls, hypocotyls, seed coat, and __________. The difference is that

1.) Monocotyledons have one cotyledon and the endosperm for nutrient. Ex. – ________

2.) Dicotyledons have two cotyledons and the endosperm dissolves. Ex. – ________

- Seeds are dispersed through many different ways. ____ and _________ are the most common.

Wind will float the seed to a new destination (______________). ___________ dispersal

often involves the animal eating the seed and ___________ it somewhere else or having the

seed become entangled in fur or feathers and being deposited elsewhere (burdock seeds). Draw

pictures of my examples.

Dandelion Burdock

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- The _____________ is the dominant form as in other tracheophytes. Flowering plants are

composed of roots, stem and leaves. The ________ function as other tracheophytes roots. That

is, they transport water and minerals up while ____________ the plant to the soil. The stem

stores and ___________ food through photosynthesis. Leaves primary function is the capturing

and converting of sunlight into energy through photosynthesis. However, in some flowering

plants, the _________ may store food and minerals. ___________ – highly modified stem

whose leaves are specialised for sexual attraction and _____________. The flower is composed

of a receptacle, which is the point on the stem where the base of the flower attaches and all of

the flower parts attach too. ___________ – outer most protective leaf-like structures. All

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sepals together are called the ________. Petals – specialised leaves that attract insects or

birds by colour and nectar glands at base of petals (corolla). Stamen – male part of flower,

composed of pollen producing ___________ and a stalk called the filament. The female part of

the flower is called the _________, which is made up of the ovary, style, and stigma (the ovule

becomes the seed and the ________ the fruit). Some plants have both male and female on the

same plant. These are called monoecious, while plants that have separate sexes are called

_______________.

Reproduction

- Male gametophyte is very tiny. Microspore mothercells (____) reside inside of the anther. Each

microspore mothercell undergoes ___________ to produce four haploid microspores (N). The

microspores are the __________ ________. Inside each pollen grain’s thick moisture proof

coat, the nucleus divides into two parts; the _________ ________ which dissolves and the

generative nucleus which ___________ again to form two sperm. When the anther dries out the

__________ ____________ are set adrift by the wind.

- Female gametophyte is attached at the base of the flower (_____). Inside the ovary are one or

more ________ containing the megaspore mother cell (2N). The megaspore mothercell will

undergo __________ to produce 4 haploid cells (N), only which one of survives. This cell

undergoes mitosis to produce eight cells. The eight cells and surrounding membrane are called

the _________ ______. The eight cells move around with ________ settling at each end and

two in the middle called the __________ _________. All will dissolve except one of the three

closest to the opening. This cell is called the egg nucleus.

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Comparative Review of Life cycles

- ______________ is the act of pollen moving from the anther to the stigma. This can occur as

self pollination or cross pollination. ______ ___________ is when a flower’s pollen fertilises

the same plants egg resulting in no sexual reproduction. Cross pollination is when wind, _______,

or insects cause the pollen from a one plant (same species) to fertilise a different plants egg

resulting in a _____________ ___ _____________ (sexual reproduction).

- Once the pollen has landed on the _______, chemicals on the stigma cause a pollen tube to begin

_________ from the pollen grain down to the ___________ (opening) in the ovule. Once the

tube is complete the two sperm travel down, enter the ovule, and one fertilises the egg to form a

zygote (2N) while the other fertilises the _____ _______ ________ (3N) in a process called

double fertilisation. The ________ (3N) becomes the __________ to nourish the embryo.

Most of our food is the endosperm of grasses (wheat, corn, and rice). The _________ is the

mature ovary and the seeds are the mature ovule.

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- The life span of flowering plants fit into three different groups; annuals, biennials, and perennials.

____________ flower and live one season, _____________flower once in the second year and

live for two seasons, and perennials flower and live for many years. You can get an idea on

lifespan based on if the plant is herbaceous or woody. Herbaceous plants are green and soft

stemmed like most garden flowers. __________ plants are flowering plants with wood stems,

and often live for many years.

Plant Parts (angiosperms)

- Leaves – are largely composed of cells that contain _______________ for photosynthesis. Outer

layer, top and bottom of leaves, is called the ____________. The remainder of the leaf is

composed of two types of _____________ cells; palisade and spongy mesophyll. Mesophyll cells

(parenchyma cells) are cells that largely contain the chloroplasts used for photosynthesis.

Palisade mesophyll is ___________ layered mesophyll, while spongy is mesophyll cells spaced by

____________ and air space for _______ exchange to occur.

- Stomata are on the underside of the leaf. They regulate gas exchange (in/out) for

___________________ to occur. They remain closed at _________ as no photosynthesis is

occurring. The opening and closing is controlled by the _________ (water pressure) in the guard

cells of the stomata.

- Veins are the bundles of vascular tissue. The ______________ of leaves is controlled by tugor

pressure in veins. The large flat side of leaves is called the ________. The petiole is the leaf

stem that attaches the leaf. __________ are small growths (_______ ___ ________) that

may grow near the base of the leaf.

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- Roots – two main purposes; anchor plant and ____________ water and minerals. There are also

two main types of roots; __________ and ___________. A ____________ is a large single

main root that grows deep with small secondary roots. Ex. – __________,________,_______

Fibrous roots are when many secondary roots anchor the plant and one main root does not exist.

Ex. – grasses.

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- The tip of a root is called the ____________. The cap lubricates the soil and is constantly

replaced by apical meristem as the cap is scraped off as root grows. ________________ grow

out of the root and increase surface area for water/mineral uptake dramatically.

- The cortex is the main cells of a root and is primarily used for ___________ ___________. The

endodermis is a thick, waxy layer of cells that encase the ___________ and ____________ to

stop water and minerals from escaping the vascular bundle. The waxy part of the endodermis is

called the Casparian strip and this is water waterproofs the endodermis. The outer layer is the

epidermal cells and they function to absorb water they come in contact with.

- Stems – tracheophyte stems differ between a monocot stem and a dicot stem. ___________

stems are lacking _________ to allow the vascular tissue to continue to increase in size. This

therefore limits stem growth for girth (not height) throughout monocot development. This is

due to the vascular bundles being _____________ throughout the ground tissue (pith) of the

stem. In dicots (______________) the vascular tissue is in a ring of cambium with the xylem on

the inside, and phloem on the outside. This allows continuous growth in both the x and y axis

continually throughout the plants development.

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- Water moves from roots to leaves via 4 actions working in conjunction.

1.) ___________________ – upward movement through narrow tubes due to molecular

attractive forces.

2.) Root pressure – difference in osmotic pressure between cells from root hair into xylem of

root. This forces water up xylem tubes.

3.) __________________ –

4.) Transpiration-cohesion theory – when water evaporates the cell becomes limp and water

diffuses in because of cohesion.

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