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Notes - Aquatic Plants - Algae

Part 1 – General Information

- Algae are considered the ____________ of plant types. They lack any internal structures that

allow the transport of ___________ _____ ____________ throughout the organism. As such,

they must live in or near a water source.

- Algae are ________________or multicellular, causing a large size range, from microscopic to the

size of a ______________ _______. Like plants, algae have a ________ _______ surrounding

the cell for support and contain photosynthetic pigments (____________________) for energy

gathering. However, algae differ in that there are no _______, stem, or _______ structures like

terrestrial plants. Many deep dwelling algae also possess accessory ______________ to aid in

photosynthesis. These pigments help absorb wavelengths of light not used by _______________

(primary photosynthetic pigment). It is these different chlorophylls and accessory pigments that

are largely used in classifying the different algae types.

- Multicellular Algae has been divided into 3 main groups; Chlorophyta, ________, and Rhodophyta.

1.) ______________ – green algae – this phylum all contain chlorophylls __ ____ __, and it is

these pigments that give the green colour. As well, this phylum also stores their energy in the

form of a complex sugar called __________. Green algae are found near the surface of

water and in very moist land. Some Chlorophyta are single celled. Ex. –Chlamydomonas.

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- ___________ green algae also exist. There are two kinds of colonies. Gonium is colonial but

each cell acts individually.

Whereas, a colony of ___________ is the second type of colony in that it is made of

individual cells that come together and act as one organism. There are ________________

strands connecting the cells for communication and movement. A Volvox colony only produces

a few specialised cells for reproduction.

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Another example is Spirogyra, this forms a threadlike colony called ________________.

They reproduce by _________________.

2.) Phaeophyta – __________ ______ - this phylum all contain chlorophylls, but they are a and

c, along with the accessory pigment ______________, and it is these pigments that give the

brown colour. As well, this phylum stores their energy in special starches and _____.

Ex. – _____________

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3.) Rhodophyta – red algae - this phylum all contain chlorophyll a (a few species also d) along with

accessory pigments called ________________. Phycobilins are excellent at absorbing

________ light, which allows these algae to live in deeper water where only blue light

penetrates. As well, this phylum stores their energy in special starches.

Part 2 – Reproduction

- Most algae life cycles are characterised by what is called ______________________________.

This expression describes how part of the algae’s life cycle is _________ (half the chromosomes)

and the other half of the life cycle is diploid (full amount of chromosomes). This trend is common

to all members of the __________ kingdom.

- The general life cycle of ___________________ characterises the life cycle for most algae.

Most of the life cycle is spent in a _____________ stage. The organism reproduces asexually

until conditions become unfavourable. Then the organism will switch to sexual reproduction.

Instead of releasing ______________ that develop into new organisms the Chlamydomonas will

release both + and – gametes. These two types will fuse (___________) and form a thick walled

___________. This zygote can survive harsh conditions and when ready will undergo _________

and release four haploid cells that grow into new Chlamydomonas.

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Part 3 - Algae Impact

- The primary role of Algae is the production of ____________. Between 50 to 75% of all oxygen

comes from algae.

- Algae are used for food in sashimi (nori wraps), ice cream, and __________________.

- Industry uses algae for everything from plastics, waxes, to deodorants.