Midterm 2- Organisms and Ecosystems

What are the three phylum for sea weeds?

Red algae, green algae, and brown algae.

Rhodophyta

Red algae

Chlorophyta

Green algae

Phaeophyta

Brown algae

What are the two forms of algae?

Filamentous and encrusting.

What are the basic parts of an algae?

The hold fast, stipe, blade, and pneumatocyst.

Holdfast

It is the bottom part of an algae which grabs onto the bottom.

Stipe

It is the stem or trunk part of the algae. It is flexible and doesn't move nutrients or water.

Blade

It is the leaf like part of algae. It has no veins. It is wrinkley to increase surface area to absorb more nutrients.

Pneumatocyst

It is the gas filled sac close to the stipe at the end of the blade.

Alternation of generations

The life cycle for algae and other organisms.

What are the two forms for organisms lifecycles?

Sporophyte and gametophyte.

Sporophyte

It creates spores. It is a diploid.

Gametophyte

It creates gametes.

Spores

They are haploids.

Describe the lifecycle for kelp.

Reproductive blades which are at the bottom of algae create spores. The spores disperse out and can create a gametophyte to form a new algae. When sperm and egg find each other, they fuse to form a sporophyte.

What are the advantages of the life history of kelp?

There is a potential for a huge geographic spread. Kelp are fecund which means they can produce up to 10 trillion spores in their lifetime. The morphology of different life stages may increase survival in more variable environment conditions.

What are the disadvantages of the life history of kelp?

Fertilization occurs after spores settle which means there needs to be a high density of gametophytes to insure successful fertilization. There is constraints over a high distance.

What kind of accessory pigment do red algae have?

Phycobilin

What kind of shell do red algae have?

Calcium carbonate.

Why are red algae good for coral reefs?

They incorporate calcium carbonate into their tissue which creates a hard substrate for coral to grown on. This helps the algae because it is less likely to break off and it is last in line to be eaten due to other algaes present.

What are the economic importance of red algae?

They are used to thicken dairy products, toothpaste, and pudding as carrageenan. They are also used as agar which helps form gels. They are used in canned meets, diet products, and to culture bacteria.

Where are green algae (chlorophyta) found?

Mostly in freshwater (often eutrophic) environments. They are also abundant in rocky intertidal areas.

What pigment causes brown algae (phaeophyta) to be brown?

Fucoxanthin

Where does brown algae (phaeophyta) live?

In deeper waters.

Why is brown algae (phaeophyta) important?

They are important in structuring coral reefs.

What are the economic uses for brown algae?

They are harvested for algin which is a stabilizer and emulsifier used for ice cream, cheese, shampoo, and shaving cream.

What is the domain for fungi?

Eukarya

What is the kingdom for fungi?

Fungi

How do fungi get energy?

They are heterotrophic and get energy by breaking down organic matter.

Describe the fungal life cycle.

They are mostly underground and contain fruiting bodies. They reproduce sexually and asexually. Most cycles involve releasing many haploid spores.

What are the uses of fungi?

They are used in beer, wine, bread, and soy sauce. They are also used in medicine such as penicillin.

What are the types of plants?

Non-vascular, seedless plants, and vascular, seedless plants.

What are the types of plants with seeds?

Gymnosperms and angiosperms.

Gymnosperms

Plants that produce seeds unprotected by an ovary or fruit.

Angeosperms

Flowering plants with fruit.

What are some adaptations plants need?

They need to deal with water loss, be able to transport water and nutrients, get nutrients, stand up on their own, and reproduce in the air.

How have plants dealt with water loss?

They have developed a stomata which can regulate water loss.

How do get and transport nutrients?

They have roots to get water or nutrients and some have a vascular system.

What are some advantages of terrestrial environments?

Plants have better access to carbon dioxide and sunlight. They had initially no predators. There is abundant soil nutrients.

What are the forms of land plants?

Bryophytes, ferns, cone bearing plants, and flowering plants.

Bryophytes

They are non-vacular seedless plants.

What are some examples of bryophytes?

Mosses, hornworts, and liverworts.

What type of plant are ferns?

They are vascular, seedless plants?

What type of plant are cone bearing plants?

Gymnosperms

What type of plant are flowering plants?

Angiosperms.

Describe mosses.

They don't have true roots. They are small and thin. They lack a vascular system and attachment. They have no support structure. They are found in wet environments.

Describe liverworts.

They grow outward and have no vascular system. They have a plate like structure.

Describe the life cycle for bryophytes.

They have a sporophyte and gametophyte stage. They have a dominant gametophyte stage. The sporophyte grows on top of the gametophyte which releases spores. Reproduction is dependent on rain. The sperm have flagella which help them swim and fertilize eggs.

What is the dominant stage for liverworts?

They have a dominant gametophyte stage.

What stage is dependent on the other?

The sporophyte is dependent on the gametophyte stage.

What is the dominant stage for ferns?

They have a dominant sporophyte stage.

Do ferns have a vascular system?

Yes.

Describe some characteristics of ferns.

They can grow upward. They have no seeds. They developed roots, leaves, and a vascular system.

What are some of the advantages of ferns' adaptations?

They have increased surface area, increasing photosynthesis. Their roots uptake water and nutrients. Their vascular system can move around the water and nutrients. This allows them to exploit dryer and shaddier environments.

What is their vascular system made of?

Lignin which is a hard strucutre.

What are the two main structures in the vascular system of ferns?

Xylen and pholem.

Xylem

It moves water and nutrients from the roots to the upper part of the plant.

Phloem

It moves sugar up and down the plant.

What are the processes that allow the movement of water in plants?

Transpiration and osmosis.

Osmosis

The flow of water from high concentration to lower concentration.

Transpiration

The process by which evaporation pulls water up a plant.

Is the sporophyte stage dependent on the gametophyte stage for ferns?

Initially, yes.

Sori

Clusters of sporangia (spores)

Describe the reproduction of ferns.

The sporophyte develops and releases gametophytes which create gametes that fertilize and form eggs. The sporophyte is initially associated with the gametophyte but losses it when it matures into a mature sporophyte.

What are some characteristics of cone bearing plants?

They have seeds and secondary growth which means the grow outward.

Describe the structure of a seed

Something with a hard coat (to lower water loss), can withstand stress, and has nourishing tissues on the inside.

Fruit

A seed-bearing structure in a flowering plant. It forms from an ovary after flowering.

What are the types of gymnosperms?

Cycads, gingkos, and conifers.

Gingkos

They have separate sexes per plant. Females produce and sticky, stinky sap.

What are the components of cone bearing trees?

The sporophyte is the tree. Male cones produce pollen and females are the pine cones.

How do cone bearing trees reproduce?

The pollen form male cones fertilizes female pine cones. The pollen inside the male cone is a gametophyte.

What is the dominant stage for cone bearing plants?

Sporophyte.

What are some characteristics of angiospems (flowering plants)?

They have true leaves, stems, roots, and flowers to attract pollinators.

Anther

The location where pollen is produced (male gametophyte).

Ovule

It located in the ovary.

Monocots

They have one cotyledon in their seed.

Eudicots

They have two cotyledons in their seed.

How can you tell apart eudicots from monocots?

Eudicots have more of a net pattern for veins. Monocots have a parallel leaf veins.

Prolifera

They are sponges.

Do sponges have tissues?

No.

What are some common challenges for animals?

They need to locate, ingest, and digest food. They need oxygen for cellular respiration and an ability to distribute it to their cells. They need to maintain water balance and temperature. The nitrogenous waste products of their metabolism need to be excreted. They must be able to reproduce successfully.

What are the phylum for sponges?

Porifera.

Are sponges sedentary, sessile, or motile?

They are sessile meaning they are attached and can't move. They are fixed to a surface.

What are the ecological importance of sponges?

They are a food source for turtles and provide a habitat for organisms.

How do sponges defend themselves?

They create poisons to defend themselves.

What are the commercial importance of sponges?

They are important for pharmaceutical use. They are also used as sponges.

Do sponges have a nervous system?

No.

How do sponges reproduce?

They do it asexually through budding and fragmentation. They also do broadcast spawning.

What is the body plant for sponges?

They are asymmetrical and radial.

Radial symmetry

Able to be cut up into multiple equal parts.

What are the classes for sponges?

Demospongiae, Hexactinellida, and Calcarea.

Demospongiae features

They are encrusting meaning they do thin growth on rocks. Examples are barrel sponges and bath sponges. They are not photosynthetic.

Hexactinellida

They are glass sponges (made of silica) that live in deep water.

Calcarea

They are calcium carbonate sponges that live in shallow waters in the tropics.

What are the two main thing sponges are made of?

Calcium carbonate and silica.

What are the main structures for sponges?

They have choanocytes, amebocytes, ostia, and an osculum.

Choanocyte

It is a flagellate cell used for feeding. it move around/waves to generate a current which moves water into the sponge.

Amebocyte (sponge structure)

It grabs food particles and distributes it around the sponge.

Ostia

They are small pores in which water flows through.