Biology B: Exam 2

what are the more derived triploblastic animals?

deuterosomes and protostomes

what are plants role in ecosytems?

Ultimate source of energy All energy and most of the carbon passes through primary producers Efficiency of energy transfer Energy loss; via heat in chemical reactions & indigestible material

what are marine worms like?

have eyes and parapodia (flat outgrowths of the body wall that facilitate gas exchange and movement). The parapodia are typically tipped by bristles termed setae.

what are some unique features of crustaceans?

have multiple specialized body segments typically hidden beneath a hard carapace or shell. They typically possess two sets of antenna and eyes mounted on stalks. The mouthparts of Crustaceans are made up of multiple pairs of appendages that vary by taxa. Some are for piercing and chewing, others are fan-like for straining

what are the features of non-vascular plants?

small, often living on marginal areas, and have many features that can be considered ancestral: -no true leaves, stems, roots, vascular tissue -need very moist areas to be live and reproduce -ancestral alternation of generation pattern

what are rotifers?

(1,800 species); numerous, very small, motile filter feeders in damp & fresh water environments -One group the bdelloid rotifers appears to have foregone sexual reproduction for 40-80 million years. How they are able to be so successful despite not having sex is one of the great questions in evolutionary biology

what are the annelids?

(segmented worms) include the marine worms, tube worms, earthworms, and leaches. They can be aquatic or terrestrial and have some 16,500 described species.

what's the deal with plant sex?

--often there will be a male flower and a female slower -plants with a single flower with both sexes are "perfect" -those with different sexed flowers are "imperfect" -single plants with both sexes=monoceious(one house) -those with individual plants that are male or female are dioceious (twohoused)

what defines angiosperm and animal coevolution?

-. This association is typically for pollination or dispersal of the seeds. The most common and important examples are with arthropods, specifically insects. -Not surprisingly, insect diversity increased rapidly at the same time Angiosperms diversified. The associations range from mutualism to exploitative. -On the right is an orchid that mimics the structure of a wasp. A male wasp will mount this structure attempting to mate with it (pseudocopulation)

when did early vascular plants evolve and what did they do?

-425 million years ago -Early vascular plants occurred in huge wet swampy areas, and their decaying material is the source of coal. -plants lacked leaves, roots,and seeds (see 28.3 in your text). However, leaves and roots do evolve later in the ferns.

whawt are some of the unique features of the nautilus species like octopi?

-Aqueous jet propulsion for movement -Octopi and squid are typically nocturnal and have cellular chromatophores that can alter color. This alteration is used for visual communication and camouflage. -The eye structure of octopi is very similar to mammals and is often cited as a example of convergence. -Octopi are extremely intelligent organisms, they display high degrees of problem solving, visual learning, and have significant memory

what is the importance of plants as artificially selected organisms?

-Artificial selection of plants by humans dates back at least ten thousand years. Maize is one of the best examples of this process --The original plant (Teosinte) originated in the new world along with potatoes, sunflowers, and chocolate -Selection for larger kernels without a tough covering has led to a highly important food crop! -Maize is just one of the many examples of domestication and artificial selection of plants

importance of cannabis as an artificially selected plant?

-Cannabis includes at least three species and are native to central Asia and South America -Probably the oldest use for Cannabis was for structural material. It can grow relatively quickly to 20 feet, and has very strong but pliable tissues -More recently, Cannabis has been selected for increase in its amount of THC which is psychoactive

how is plant related to carbon?

-Carbon is used in producing sugars for energy use by the plant and are also used to construct plant tissues -When the plant uses sugars as fuel the carbon is released back into the atmosphere as CO2. Therefore, plants are both a source and a sink for carbon. However, plants are a net sink for carbon because their tissues take so long to break down. -Carbon cycling is critical because carbon is a key element of the tissues of all organisms and CO2 is a greenhouse gas that traps heat in the upper atmosphere!

what are the diverse body forms in mollusks?

-Dorsal tissue layer, the mantle, excretes the hard shell material -Digestive tract and gills show significant variation especially in bivalves and snails -Structure of the "foot" varies from a general amorphous extension in snails to arms (not tentacles) in Cephalopods -Neurology varies from limited and mostly "smelling" in bivalves, to extensive and highly acute (e.g. vision) in some Cephalopods

what was the worst recent ecological disaster?

-During the 1930's the worst recent ecological disaster occurred in the great planes of North America when drought was combined with the removal of native grasses and other plants for farming -Without significant root masses rich soils runoff with hard rains or can be carried off by strong winds. These soils generally end up in the ocean. These nutrients typically take thousands of years to return from the ocean

what is the cuticle and who has cuticles?

-One Ecdysozoan feature is a hard external covering secreted by the epidermis, this is called the cuticle. The cuticle serves as external support and protection (exoskeleton). In some forms (nematodes) the cuticle is thin and flexible, in others it is quite firm. -cuticle forms all at once and then cannot grow along with the organism. Therefore, the cuticle must be shed or molted periodically to allow for growth of the organism. The next layer of the cuticle is already forming when the older is shed. This new layer expands and hardens in a few hours to a few days. This is a period of danger for the organism.

what is the main carbon sink in our planet?

-The tree species that dominate forests hold massive amounts of carbon for long periods of time. -Unfortunately deforestation is occurring at a devastating rate -South America, Africa, Asia, and the boreal forests are decreasing fast -Some parts of North America and Europe are experiencing growth

how are nematodes involved with infection?

-There are hundreds millions of people per year infected by nematodes, they include the cause of... trachinosis, alanosis and elephanatosis

how are crustaceans critical to marine ecosystems>

-are extremely small and makeup the "consumers" within the ocean's plankton. Marine ecosystems are almost totally dependent on planktonic organisms including bacteria, Protists, and crustaceans

what are the ticks and mites?

-are highly speciose and numerous. Note: lice, although similar in ecology, are insects. -are typically small, host specific parasites of animals and plants. They typically attach themselves securely to their host and then either feed off skin or burrow to ingest the fluids of the host. Insects are often the host of choice for mites and ticks

what is greenhouse gas? main source?

-have become the center of media attention because human activity has caused a huge increase in atmospheric CO2. The main source of this is the increasing use (burning of) fossil fuels: Coal, Petroleum (oil), natural gas

are crabs, lobsters, shrimp and crayfish decapods?

-implies they have ten legs which is not always true, however. This group has three body parts but this is often obscured by a thick shell that covers the head and thorax. Most species are marine, and almost all are aquatic. -This group often has one set of legs with enlarged "claws". Lobsters often have dimorphic claws one for "crushing" the over for "pinching or "slicing". Female decapods typically carry eggs on their body until hatching occurs.

what is a strange feature of angiosperms?

-is double fertilization -the male gamete carries two sperm. One of these fertilizes the egg and goes on to become the offspring. The other sperm fertilizes two other haploid nuclei of the female to form a 3n nucleus and tissue. This tissue then grows and divides and nourishes the primary embryonic tissue. Wow!

what is the principle novel feature of gymnosperms?

-is their spoors and seeds; -Male "spoors" are spread by the wind and therefore need much less water than their ancestors -Fertilized eggs (seeds) are covered in a tough seed coat that resists physical damage and dehydration

what do nitrogen fixing bacteria do

-produce ~170 million metric tons of fixed nitrogen per year. Compare this with the total human industrial production of 80 million tons that requires a great deal of energy to accomplish. Nitrogen is essential in the chemical structure of molecules of living organisms...

what is the ultimate limiting reaction for life on our planet?

-termed Primary Production RXN: 6 CO2 + 6 H20 C6H12O6 + 6 O2 -. Cellular respiration is the use of the carbon molecule(s) often in the presence of a strong oxidizing agent (O2) to form chemical energy.

what is a major misnomer considering climate change?

-that patterns of human habitation and farming can simply move...

what are the most commons seedless vascular plants?

-the ferns -Like nonvascular plants, the ferns require wet environments for reproduction, the sperm require water to swim to the eggs. But they do have a vascular system and simple roots which allows for vertical growth.

what are angiosperms?

-the flowering plants... had their origin approximately 150 MYA... diversified and became the dominant land eukaryote about 75 MYA -Currently there are more than a quarter million species of angiosperm

what is the general trend of ALT of gens across plant taxa?

-the more ancestral plants tend to be gametophyte (n) dominant -the more derived plants are sporophyte(2n) dominant

what are the mollusks?

-the most diverse of the Lophotrochozoans and second only to Arthropods among animals. To date there are approximately 100,000 described species of mollusk. These include the scallops, clams, snails, slugs, nudibranchs, squid, octopi, and nautili. -are non-segmented. Further, all mollusks either have a hard shell or have lost this feature through evolutionary history. Inside their shell mollusks are soft-bodied. -tend to have gills for gas exchange and an open circulatory system. Circulation involves a pumping "heart" connected to blood vessels that empty into open sinuses in the body where gas exchange with the tissues takes place

what are bogs and what kind of plants usually make them up?

-usually bryophytes.. act as a large, critical carbon sink in cool northern latitudes -bogs are a big source of CO2, the top of bogs are alive but bottom mass can decompose and release CO2

what evolutionary traits helped adapt the gymnosperms to land?

-woody stem and secondary growth that allows for much larger size -thicker waxy cuticle covering the leaves to prevent water loss -larger root system for support

what are some explanations for arthropod success?

1. the combo of an external skeleton that can evolve many different shapes and features 2. the tendency to be highly specialized on one particular host, food, and habitat 3. separation of larval and adult niche in some arthropods.. specifically insects... babies dont compete with adults

what are the reasons for the fact that very similar body forms and life history strategies evolve over and over despite very different evolutionary starting points?

1. the physical environment places consistent physical constraints such as: gravity, predatory-prey relationships etc. 2. organisms will typically have genetic architecture and physcially evolutionary paths (hox genes)

what is an example of the mutually beneficial partnership between plants and fungi?

1.Plants roots are responsible for taking up water and nutrients from the soil. But most plants do not have enough roots to perform this task! (you can test this by treating plants with fungicide) 2. They rely on associations with Fungi to increase surface area for absorption. Most of what we think of as plant root tissue is actually Fungi...

Today of all medical compounds have critical plant molecules. Only __% of plants species have been investigated for medical use fill in blanks...

25%... 2%

when and what were the first vascular plants with seeds?

300 million years ago -called gymnosperms

what is the photosynthesis reaction?

6 CO2 + 6 H20 ---> C6H12O6 + 6 O2

what takes up 56% of our caloric intake? 70%?

6 plants, 14 plants

what is parasitism in protostomes?

: evolved repeatedly; protostomes parasitize plants and animals

what are arachnids like as predators?

Arachnids typically have chemical venom that helps to incapacitate their prey. Most are sit-and-wait predators and many use secreted "webs" to capture and hold prey.

what takes up %14 of human caloric intake?

Bananas, beans, soybeans, sorghum, barley, coconuts, sugar cane, sugar beets

why are we able to examine patterns of evolutionary change in protostome nature?>

Both major clades of the Protostomes contain diverse taxa of organisms and large species numbers (diverse and speciose).

what are the nonvascular plants sometimes referred to as? and what do they include?

Bryophytes... they include The most ancestral terrestrial living plants, and those that appear most similar to the earliest fossil plants -, include the liverworts, mosses, hornworts

summary of photosynthesis?

Chlorophyll molecules, when struck by photons, change light energy into chemical energy As you should know the final outcome is sugars or other carbohydrates (starch) that are used in cellular respiration throughout the plant

what is alternation of generations?

Many plants have free living diploid (2n, sporophyte) and haploid (1n, gametophyte) life history stages (generation). This is odd to us because the vast majority of animals lives are spent in a diploid stage.

how do nematodes feed?

Most nematodes are free living predators (or detritivores) consuming Protists, bacteria, fungi, and microscopic animals. A small fraction of nematodes are internal parasites of animals or plants.

what are flatworms?

Most of the 25,000 species of flatworm are internal parasites of animals, including humans. Internal parasites often have a loss of discernable features. Includes tapeworms, and flukes such as Schistosoma (adult)

what do the arthropods include?

Myriapoda (Millipedes, Centipedes; 14,000 species) Chelicerata (Spiders, Ticks, Mites, Horseshoe Crabs, Scorpions, Daddy Longlegs; 98,000 species) Crustaceans (Barnacles, Isopods, Copepods, Shrimp, Lobsters, Crabs; 52,000 species) Insects (Hexapods) (Beetles, flies, Ants, Bees, Wasps, Dragonflies, Butterflies, Grasshoppers, Crickets, Bugs, etc.; 1,000,000+ species)

what is considered the most important eukaryote for human survival and why?>

RICE... is a type of grass, a monocot flowing plant -Utilization predates written history & Currently provides over 20% of human dietary energy -Nutritional quality depends on the strain used. However, rice does not have all of the essential amino acids so a diet of rice must be supplemented.

what is the evolution history of plants>

Recall that plants have their origin in aquatic green algae. Approximately 500 million years ago the first land plants evolved. Much of their subsequent evolution was associated with adaptations for living on land versus their ancestral aquatic environment.

what takes up %50 of human caloric intake?

Rice, wheat, maize, potatoes, manioc, sweet potatoes

what is mycorrhizae?

Root tissue interacting with Fungi; the root & fungi is given the collective name Root tissues actively communicates with, and induce fungal hypha to invade the plant root tissue. This relationship increases the plant-root surface area by The fungi receive energy in the form of simple sugars from the plant. Recent data has shown that not only are the mycorrhizae critical for the health of the plant, but this system often directly connects one plant to another, sometimes even of different species. This allows individuals to share resources and communicate! This has been shown elegantly though radioactive tracers injected into forest trees

what are symptoms of nematode infections?

Symptoms are often subclinical until the number of nematodes are extremely high and treatment can be difficult. Parasitic nematodes often have life-cycles that include multiple hosts.

how is O2 and Carbon transformed for use?

The transformation of both of these molecules into a useable form is ONLY done by cyanobacteria and their relatives!

what makes nematodes critical members of terrestrial and some aquatic ecosystems?

There are 25,000 described species but many multiples of this number likely exist. Your text states that a single rotting apple on the ground may have as many as 90,000 nematodes. Their enormous numbers and biomass along with being a key trophic connection between protists and larger animals

what does xylem in plants do?

Water from the soil is transported up via it

what are the chelicerata?

a type of arthropod... consists of the spiders, mites, ticks, scorpions, horseshoe crabs and daddy longlegs. The vast majority of these are terrestrial, just a few are aquatic. Like the Myriapods they have a distinct body and head region. Many Chelicerata have eight legs.

what are arachnids?

a type of chelicerata within the arthropods... made up of mostly spider-like forms, but also includes the horseshoe crabs (note these are not true crabs). Most species are terrestrial and have four pairs of legs, with an additional pair that has been modified into piercing mouth parts

what are barnacles?

a type of crustaceans -are filter feeding organisms that resemble mollusks externally. The wispy structures are legs extended outside of their shell to filter out small prey. Their "head end" is positioned downward. Barnacles tend to live in shallow water and in great numbers

how is better locomotion important for protostomes?

allow prey to escape more easily, but also predators to capture prey more easily. This sets up a evolutionary "arms race" that may facilitate evolution and diversity

what are the diverse feeding structures of protostomes?

allow species to take advantage of many food sources and niches.

what does the tardigrades ability to pull in head and limbs do>

allows them to withstand: High & low temperature, ionizing radiation, severe dehydration, extremes in pressure, even the vacuum of space!

what are crustaceans?

an arthropod... include the lobsters, shrimp, crayfish, crabs, along with the less familiar isopods, copepods, and barnacles. The Crustaceans are the dominant arthropods in marine environments. Many have noted that Crustaceans dominate aquatic environments while insects dominate terrestrial environments. A few Crustaceans such as the land crabs and pillbugs (roly-polies) are terrestrial.

what are tardigrades?

are microsopic, slow moving aquatic ecdysozoan protostomes... when environmental conditions become unsuitable, they pull in limbs and head

what do dead plant bodies do?

bodies break-down, form soils, and cycle nutrients and energy

what is elephantiasis?

can cause extreme swelling in the affected tissue. This commonly occurs in the legs, but can occur in the genitals, arms, and face. If untreated, infected tissues often develop open sores and become infected. Infected individuals are often stigmatized and left untreated in their communities

what about nematodes and crop plants?

can cause significant damage to crop plants, but other nematodes are actually beneficial by consuming other plant parasites and used as biological controls

what's a neat ability that octopi + cuttlefish have?

change their shape significantly. This allows the individual to mimic the texture of their background to a amazing extent. Further, the lack of a shell allows them to squeeze into amazingly small spaces.

what does the name segmented worms come from?

comes from the tendency for them to display a strong pattern of segmentation.

what are hard body coverings like for protostomes?

coverings (exoskeletons and shells): evolved independently in many groups. Important for locomotion and protection from predation

what is the protostome complex life cycle?

different stages specialize on different resources

what are nematodes?

ecdysozoan protostomes... are typically microscopic and extremely common in terrestrial and aquatic soils

what is segmentation in protostomes?

facilitates evolution of increased size and independence of body part movement

what are centipedes?

first set of legs are modified into pincer-like mouthparts that inject venom into the prey. The largest of the centipede is ~ 12 inches long, the longest millipede ~ 1 meter in length.

what are the two broad groups of plants?

green algae and land plants

What can we deduce about evolution from the body shapes of Lophotrochozoans vs. Ecdysozoans?

in both clades there appear appear to be certain body forms that evolution has produced... small fitter feeding forms, a diversity of worm-like forms and larger organisms that rely on more complex nervous system for survival and prey capture

what are cephallopods generally?

include some of the most active, intelligent, and largest of the Protostomes... 800 species

what are the green algae?

include the most recent ancestors of land plants, and they are especially important in aquatic systems where they provide oxygen and food for other aquatic organisms.

what's the deal with earthworms?

ingest soils and digest organic materials. Their excretion produces enriched soil that is critically important for plant growth. The biomass of these organisms is very high (10^6 per acre). These organisms are hermaphrodites, each individual is both male and female

how is protostome diversity defined?

it is difficult to comprehend. They span the range from very small organisms (rotifers) to Mollusks such as octopi and squid, and Arthropods such as the spiders, and the insects.

what does breakdown of plant tissue do?

it is the source of soils that allows other plants to grow and terrestrial ecosystems to flourish.

what are some of the less speciose insect groups?

like the Odonata, dragonflies & damselflies contain 5,000+ species. In comparison all the combined mammals only amount to ~4500 species

what are the most speciose of segmented worms?

marine worms

what arthropod can serve as vectors for disease?

mites and ticks... facial mites (Demodex)

what is rhizobia?

nitrogen fixing bacteria>

what are the most important groups in terrestrial ecosystems?

plants and fungi

what are the most numerous, speciose, and important of the triploblastic animals?

protostomes

what are the nautilus species?

retain a external secreted shell that has been lost in the octopi and squid. In the Ordovician (475 mya) squid-like cephalopods with long straight shells were extremely common

what are the features that make protostomes so successful?

segmentation, complex life cycles, parasitism, diverse feeding structures, hard body coverings, better locomotion

what is monoceious?

single plants with both sexes

what is the one group of animals that exemplifies diversity and numbers of individual eukaryotres?

the arthropods

what is schistosoma?

the second most prevalent disease after malaria. It's egg stage thrives in contaminated water where it invades the skin of its primary host. Secondary hosts are typically snails. Once in the host the pathogen can take host proteins and adhere them to their exterior! Early stages of infection are often accompanied by skin lesions and irritation.

what are some of the largest insect groups?

they are arthropods... There appears to be enormous numbers of: True bugs (Hemiptera); ants, bees and wasps, (Hymenoptera); beetles (Coleoptera); flies (Diptera), and butterflies & moths (Lepidoptera).

what are the millipedes like?

they are myriapods.. a type of arthropod -Millipedes are mostly scavengers of dead plant material. However, centipedes are ravenous predators. They have reduced or absent eyes and use chemo-sensation and tactile sensation via their antenna

what does the phloem do?

transports sugars from the photosynthetic tissues to other plant tissues

what is the ichthysoaur?

~ 150 mya, evolved from lizard-like reptiles. Note the shape of the body, the paddle shaped limbs, extension of the head, dorsal fin, etc

dolphin and icthysoaur relation?

~ extant, evolved from a wolf-like mammal. Note the very similar features, but the differences as well.