BIOLOGY FINAL EXAM
There are many plants in the tropics of Central and South America that have very large fruits that are dispersed by cows, horses, and donkeys. What is likely true about these fruits?
They were probably dispersed by herbivorous mammals that went extinct thousands of years ago.
Humans and chimpanzees are sister species. Explain what that means.
This means that chimpanzees are the closest related organisms to humans and that they both share a common ancestor
Three mitotic divisions within the female gametophyte of the megaspore produce
three antipodal cells, two polar nuclei, one egg, and two synergids.
what are the 2 types of meristematic tissue? why?
apical and lateral; competitive advantage -apical: upward growth (stem/branches) -lateral: growth in girth (trunk)
In some angiosperms, other floral parts contribute to what is commonly called the fruit. Which of the following fruits is derived mostly from an enlarged receptacle?
apple
Which of the following is (are) unique to animals?
nervous conduction and muscular movement
gymnosperms
no fruiting body
Basidiomycota fungus
no haploid fruiting stage
Why is there a tradeoff between transpiration and photosynthesis? what are 2 adaptations in plants in arid environments?
open stomata: transpiration and gas exchange for photosynthesis, BUT causes the plant to lose water
What features not present in seedless plants have contributed to the enormous success of seed plants on land?
(1) The gametophytes of seed plants are reduced and dependent upon the parent sporophyte which protects them (particularly in the case of the female gametophyte). (2) Pollen is covered with sporopollenin which is resistant to physical factors in the environment. (3) The structure of the seed protects the next generation sporophyte and allows it to remain dormant until conditions are right for germination, development and growth.
Distinguish between primary and secondary growth.
(1) primary growth occurs at the apical meristems, where the structure is elongated. (2) secondary growth occurs at the vascular cambium and cortex cambium, where the structure is increased in width
PLANT PHYLOGENY
(from left to right) Charophycea, bryophytes (3), tracheophytes: [spermatophyta: [lycophyla, pterophytes, gymnosperms: [cycadophyla, gnetophyla, ginkgophyla, coniferaphytes], angiosperms: [dicots, monocots]]
ANIMAL DEVELOPMENT
-bilateria>triploblastic>deuterostome -bilateral: radial cleavage, gastrula stage -blastosphere=opening (future *******) -archenteron=inside circle (becomes mesoderm) -endoderm=inner layer -ectoderm=outer layer
POP QUIZ
-mature male gametophyte=3 cells -mature female gametophyte=7 cells/8 nuclei -xlyem (dead): water transport -phloem (alive): transport of nutrients/sugar -insect pollination of plants is NOT exclusive to angiosperms
Angiosperm chromosomes/cells
-petals/plants have the same amount of chromosomes -endosperm (3N) has 1.5 times as many cells as filament -synergid (N) cell has half as many cells as stem (2N)
METAZOAN PHYLOGENY
1. bilateral symmetry (porifera) 2. multi-cellularity (ctenophora) 3. true tissues (ctenophora) 4. posterior/anterior Hox genes and protostome development (acoela) 5. radial symmetry (lophotrochozoa)
order of evolution of plant traits:
1. phragmoplastic cytokinesis / cellulose in cell wall (charophytes) 2. true vascular tissue (tracheophytes) 3. sperm that lack flagella (pterophytes) 4. branched roots (pterophytes) 5. sporangia encased in spori (ON pterophytes) 6. seeds (gymnosperms) 7. insect pollination (ON cycadophyta) 8. vessel elements (ON gnetophyta) 9. fruits, flowers, vessel elements, insect pollination (angiosperms) 10. single cotyledon (monocots)
Arrange the following in the correct sequence, from earliest to most recent, in which these plant traits originated:
3 → 2 → 1 1. sporophyte dominance, gametophyte independence 2. sporophyte dominance, gametophyte dependence 3. gametophyte dominance, sporophyte dependence
Approximately how far back in time does the fossil record extend?
3,500,000,000 years
What is the probable sequence in which the following clades of animals originated, from earliest to most recent?
5, 3, 2, 1, 4 5. bilaterians 3. deuterostomes 2. vertebrates 1. tetrapods 4. amniotes
What are some of the benefits that lichen algae can derive from their relationship with fungi?
A suitable environment for growth, retention of water and minerals, protection from sunlight, and protection form being eaten.
Which one of the following statements about transport of nutrients in phloem is false?
Companion cells control the rate and direction of movement of phloem sap.
Protostomes that have an open circulatory system and an exoskeleton of chitin are part of which phylum?
Arthropoda
Members of this phylum produce two kinds of haploid spores, one kind being asexually produced conidia:
Ascomycota
In the following diagram of an embryo sac of an angiosperm, which cell(s), after fertilization, give(s) rise to the embryo plant?
B
A major evolutionary episode that corresponds in time most closely with the formation of Pangaea was the
Permian extinctions.
In which phylum are mushrooms and toadstools classified?
Basidiomycota
Explain why forams have such a well-preserved fossil record.
Because foram tests are hardened with calcium carbonate, they form long lasting fossils in marine sediments and sedimentary rocks
How do the main similarities and differences between seedless vascular plants and nonvascular plants influence function in these plants?
Both have flagellated sperm that require moisture for fertilization; this shared similarity poses challenges for these species in arid regions. Seedless plants have true leaves and roots when compared to bryophytes which allows more surface area for photosynthesis and improves ability to extract nutrients from soil
Which of the following was not a challenge for survival of the first land plants?
animal predation
Almost all of the major animal body plans seen today appeared in the fossil record over 500 million years ago at the beginning of the
Cambrian peridod
Which is a true statement about angiosperm carpels?
Carpels surround and nourish the female gametophyte.
Which of the following is a diploblastic phylum of aquatic predators?
Cnidaria
Describe the evidence that cnidarians share a more recent common ancestor with other animals than with sponges.
Cnidarians possess true tissues, while sponges do not. also unlike sponges, cnidarians exhibit body symmetry, though it is radial and not bilateral.
What is the benefit of seed dormancy?
Dormancy assures survival of the plant since germination does not occur until conditions are favorable for plant growth.
Which of these illustrates the correct representation of the binomial scientific name for the African lion?
Panthera leo.
Contrast the cellular and DNA structures of prokaryotes and eukaryotes.
Eukaryotic: true nucleus, double membrane, linear DNA made of chromosomes, 5 types of RNA, larger ribosomes, more space, membrane enclosed organelles Prokaryotic: smaller, no nucleus, nucleoid, circular DNA, 3 types of RNA, no organelles
Compare and contrast the nutritional mode of a fungus with your own nutritional mode.
Humans and fungus are heterotrophs. In humans, we ingest relatively large pieces of food and digest the food within our bodies. While in fungus, it digests its food externally and then absorbing the small molecules that result form digestion.
Which of the following statements about xylem is incorrect?
It transports mainly sugars and amino acids.
which of the following interactions do not include mutualisms?
NONE, all are mutualisms... lichens, endophytes, bark/ambrosia beetles, mychorrhizae
Which of the following is a true statement about growth in plants?
Some plants lack secondary growth.
Identify plant organs that are sugar sources, organs that are sugar sinks, and organs that might be either. Explain.
The main sources are fully grown leaves (by photosynthesis). Roots, buds, stems, expanding leaves, and fruits are powerful sinks because they are actively growing. A storage organ may be a sink in the summer when accumulating carbohydrates, but a source in the spring when breaking down starch into sugar for growing shoot tips.
Which of the following statements provides the strongest evidence that prokaryotes evolved before eukaryotes?
The oldest fossilized cells resemble prokaryotes.
Given the differences between angiosperms and gymnosperms in the development of the integument(s), which of these statements is the most logical consequence?
The seed coats of angiosperms should be relatively thicker than those of gymnosperms.
In what pattern does the vascular cambium form new vascular tissue? why?
The vascular cambium forms a ring: secondary xylem forms a wooden interior and secondary phloem forms a bark exterior. Since the phloem transport sugars, sap moves up the tree by the phloem in the bark.
Would you expect a tropical tree to have distinct growth rings?
Tropical evergreen forests or tropical rain forests have no dry season as there is rain spread throughout the year and temp. variations are minimal . So the growth rings are indistinct ; But they are there !
Which of the following is true of seedless vascular plants?
Whole forests were dominated by large, seedless vascular plants during the Carboniferous period.
All of these might have been observed in the common ancestor of chondrichthyans and osteichthyans, except
a swim bladder.
what are the implications of a the hypothesis that makes ctenophora a sister taxon to metazoans?
a. true tissue evolved twice OR b. true tissue was lost in sponges (sister to metazoans)
What is the primary role of a mushroom's underground mycelium?
absorbing nutrients
what led to rise of gymnosperms?
after permian extinction and the formation of Pangaea, aridity caused mass extinctions of carboniferous forests; gymnosperms took over b/c they can survive in dry climates with the adaptation of seeds
Biologists suspect that endosymbiosis gave rise to mitochondria before plastids partly because
all eukaryotes have mitochondria (or their remnants), whereas many eukaryotes do not have plastids.
The opening of stomata is thought to involve
an increase in the osmotic concentration of the guard cells.
how do the life cycles of gymnosperms and angiosperms differ?
angiosperms have double fertilization - produces 3N endosperm (supports growth of embryo)
Which of the following pairs are the best examples of homologous structures?
bones in the bat wing and bones in the human forelimb
We know from the experiments of the past that plants bend toward light because
cell expansion is greater on the dark side of the stem.
The most recent common ancestor of all land plants was probably similar to modern-day members of which group?
charophytes
A shared derived characteristic for members of the arthropod subgroup that includes spiders would be the presence of
chelicerae
Which of the following are elongated in the oral-aboral axis?
class Holothuroidea (sea cucumbers)
what combination of environmental and morphological change is similar in the evolution of both fungi and plants?
colonization of land and loss of flagellated cells
which structure is incorrectly paired with its tissue system?
companion cell ground tissue
In the life cycle of an angiosperm, which of the following stages is diploid?
microsporocyte
what ploidy level do basidiomycotes spend most of their time?
diploid
Which of the following is a shared characteristic of all chordates?
dorsal, hollow nerve cord
if we were to separate these eight cells and attempt to culture them individually, then what is most likely to happen?
each cell may continue development, but only into an inviable embryo that lacks many parts
Protists are alike in that all are
eukaryotic
A trend first observed in the evolution of the earliest tetrapods was
feet with digits.
Which of these structures are most likely to be a component of both chytrid zoospores and motile animal cells?
flagella
A lophophore is used by ectoprocts and brachiopods
for feeding.
The first appearance of free oxygen in the atmosphere likely triggered a massive wave of extinctions among the prokaryotes of the time. Why?
free oxygen attacks chemical bonds and can inhibit enzymes and damage cells. as a result, prokaryotes that had thrived in anaerobic environments would have survived and reproduced poorly in oxygen-rich environments, driving many species to extinction.
mycorrhizae
fungal net around plant roots; supply plant with certain nutrients and plant supplies fungi with carbs
At which developmental stage should one be able to first distinguish a diploblastic embryo from a triploblastic embryo?
gastrulation
Which of these genetic processes may be most helpful in accounting for the Cambrian explosion?
gene duplication
Penicillin is an antibiotic that inhibits enzymes from catalyzing the synthesis of peptidoglycan, so which prokaryotes should be most vulnerable to inhibition by penicillin?
gram-positive bacteria
What distinguishes a coelomate animal from a pseudocoelomate animal is that coelomates
have a body cavity, whereas pseudocoelomates have a solid body.
which device is used to study liquid flow through xylem?
high pressure flowmeter: transpiration, tension and cohesion create (-) pressure
ferns
homosporous - only one kind of spore
what is an imperfect flower? how might imperfect flowers aid in preventing self-fertilization?
imperfect flower=one with only male (stamen) or female (carpel) gametophyte; dioecious flowers separate gametophytes to prevent self-fertilization
deuteromycete
imperfect fungus (no known sexual phase); produce septate mycelia/yeasts
Only certain prokaryotes can perform nitrogen fixation, but nitrogen-fixing prokaryotes are not known to live inside animals. Thus, how do animals gain access to fixed nitrogen?
ingest nitrogen fixers, plants that harbor nitrogen fixers, other animals
cubozoa
jelly; no digestive tract; single opening for ingestion/excretion
The correct sequence, from the most to the least comprehensive, of the taxonomic levels listed here is
kingdom, phylum, class, order, family, genus, and species.
Which feature excludes it from possibly being a leech?
lack of external segmentation
Sponges and cnidarians are among the fossilized animals found in both the Ediacara Hills and the Burgess Shale from the Rocky Mountains of British Colombia. This observation requires that
land that now comprises Ediacara Hills and Rocky Mountains was underwater about 550 million years ago
Which of the following use light energy to synthesize organic compounds from CO2?
photoautotrophs
For mycelia described as heterokaryons or as being dikaryotic, which process has already occurred, and which process has not yet occurred?
plasmogamy, genetic recombination
What effect does "pinching back" have on a houseplant?
produces a plant that will grow fuller
What do fungi and arthropods have in common?
protected by coats constructed of chitin.
Based on studies of plant evolution, which flower part is not a modified leaf?
receptacle
Which group is incorrectly paired with its description?
red algae-acquired plastids by secondary endosymbiosis
What are the challenges of estimating the absolute ages of old fossils?
sediment is subject to erosion; short half-life of carbon-14, 5730 years, makes the reliable only up to about 75,000 years;
What is a major difference in the life cycles of byophyta and spermatophyta that is probably an adaptation to land?
seed production; aridity was a major challenge of terrestrial life, plants probably evolved seeds to protect embryos until conditions were suitable for growth
Current research best supports the hypothesis that the jaws of vertebrates were derived by the modification of
skeletal rods that had supported pharyngeal (gill) slits.
If you were able to walk into an opening cut into the center of a large redwood tree, when you exit from the middle of the trunk (stem) outward, you would cross, in order,
the annual rings, phloem, and bark.
The result of heterospory is
the existence of male and female gametophytes.
The term "homoplasy" is most applicable to which of these features?
the legless condition found in various types of extant lizards
An adult animal that possesses bilateral symmetry is most certainly also
triploblastic.
The amount and direction of movement of water in plants can always be predicted by measuring which of the following?
water potential (Ψ)
uppose George Washington completely removed the bark from around the base of a cherry tree but was stopped by his father before cutting the tree down. The leaves retained their normal appearance for several weeks, but the tree eventually died. The tissue(s) that George left functional was (were) the
xylem.