Biology Exam 4

What is the evolutionary relationship among archaea, bacteria, and eukarya? Answers: Archaea and eukarya share nucleic acid similarities, so eukarya split off from archaea. All three domains are equally distant from the most primitive common ancestor, a protocell. Since archaea are the most primitive, archaean ancestors gave rise to bacteria that in turn gave rise to eukaryotes. Bacterial ancestors gave rise to both archaea and to eukaryotes as two separate side branches.

Archaea and eukarya share nucleic acid similarities, so eukarya split off from archaea. Response Feedback: Based on biochemical evidence, it is thought that domain Bacteria is not closely related to either domain Archaea or domain Eukarya. Archaea and Eukarya share many biochemical similarities and some molecular similarities.

Which of these is a correct description of a form of horizontal gene transfer in bacteria? Answers: Crossing-over occurs between paired chromosomes in meiosis. Transduction occurs when a live bacterium picks up DNA from dead bacteria that have shed it into the environment of the living cell. Transformation occurs when a bacteriophage carries a bit of DNA from a previous host cell to a new host cell. Conjugation occurs when a cell passes DNA to another cell by means of a sex pilus.

Conjugation occurs when a cell passes DNA to another cell by means of a sex pilus. Response Feedback: While bacteria do not use sexual reproduction, they do have three known methods of combining genetic material. First, there is conjugation, where genetic material is transferred from one bacterium to another via a sex pilus. Next is the process of transformation where the DNA of a dead bacterium is taken up from the surrounding medium by a live bacterium. And finally there is transduction. In this method a virus carries portions of bacterial DNA between two bacteria.

Which of these is NOT a characteristic of a shark? Answers: skeleton of cartilage ability to sense electric currents in the water ability to detect blood in minute amounts ability to sense pressure of other swimming objects a sucker used to attach to prey

a sucker used to attach to prey Response Feedback: Sharks are members of class Chondrichthyes, the cartilaginous fishes and have very acute senses. They are able to detect small quantities of blood, pressure changes in the water, and electric currents. Sharks are also jawed fishes and do not have suckers, but rather a large number of teeth used to catch and devour prey.

A major evolutionary trend among plants is Answers: a reduction in the size of the sporophyte and an increase in the size of the gametophyte. a reduction in the size of the gametophyte and an increase in the size of the sporophyte. an increase in the size of both the sporophyte and the gametophyte. a decrease in the size of both the sporophyte and the gametophyte

a reduction in the size of the gametophyte and an increase in the size of the sporophyte. Response Feedback: An evolutionary trend seen in plants is that the haploid gametophyte becomes reduced in size and the diploid sporophyte has increased in size. Since the sporophyte has become reduced in size, it can be enclosed and packaged as a seed which can then be disbursed.

Amoebae Answers: have pseudopodia. have a nucleus are heterotrophic. all of the above are true. Only A and C are true.

all of the above are true

Which of these characteristics first developed in reptiles? Answers: scales on skin amniotic egg animals with lungs four-legged body

amniotic egg Response Feedback: Scales and the skull and vertebral column are seen in fish and a four-legged body and lungs are seen in amphibians. Both of these phyla developed before reptiles. What is not seen in these earlier forms are amniotic eggs.

The largest animal group, both in number of species and number of individuals, is the Answers: crustacea. reptiles. insects. annelids.

insects Response Feedback: Insects likely have over one million species and are extremely diverse. They are more species-rich and diverse than all other types of life.

The organism represented in the above image Answers: is a chromalveolate. is an excavate. is in the genus Euglena. is in the genus Amoeba. makes pseudopodia. is a flagellate.

is an excavate. is in the genus Euglena. is a flagellate.

A chain of asexual spores produced by a sac fungus is called Answers: a mycelium. a basidiospore. an ascospore. a conidia.

a conidia

The mycelium is a mesh of filaments, each of which is called Answers: a hypha. a basidiospore. a conidium. an ascospore.

a hypha Response Feedback: Fungi have a filamentous body; an individual filament is called a hypha, while the collective mass of filaments is called a mycelium.

A plant that makes seeds but not flowers would be Answers: a moss. a pine tee. a grass. a fern.

a pine tree

Put these in the order in which they occurred over evolutionary time. Answers: 1. evolution of the embryo 2. evolution of vascular tissue 3. evolution of the seed 4. evolution of the flower

selected answer: 1. evolution of the embryo 2. evolution of vascular tissue 3. evolution of the seed 4. evolution of the flower

A recent study of the marine hawksbill turtle's stomach contents revealed that sponges constitute a major portion of their diet. Sponge beds are generally protected from predators by the sponge's calcium and silica crystals, but these were found in quantity in the turtles' digestive systems. These structures that protect the sponges from most predators, but not turtles, are Answers: spicules. amoebocytes. the osculum. spongin.

spicules Response Feedback: Sponges have an internal skeleton made up of small, needle-like structures that have one to six rays made of calcium or silica crystals; these structures are called spicules.

Which life cycle phase is diploid in moss? Answers: sporophyte generation spores gametophyte generation gametes

sporophyte generation Response Feedback: With alternation of generations, plants cycle between generations that are haploid and give rise to gametes. This is called the gametophyte generation. A generation that is diploid and gives rise to spores after meiosis is called the sporophyte generation. This cycle is found in all plants and only varies as to which generation is larger.Leafy plant with no true roots

During pollination in angiosperms, pollen grains will stick to the enlarged knob in the center of the flower called the Answers: anther. stigma. ovule. style. ovary.

stigma Response Feedback: The sticky stigma would trap pollen that landed there and a pollen tube would grow from the pollen grain down to the egg in the ovule, fertilizing the egg.

At which number on the phylogenetic tree did vertebrates evolve four limbs, becoming tetrapods? Answers: 1 2 3 4 5

4

Which of the following organisms move about by means of pseudopodia? Answers: Paramecium caudatum Chlamydomonas Amoeba proteus trypanosome

Amoeba proteus Response Feedback: Pseudopods are projections of the plasma membrane formed through cytoplasmic streaming. The process allows some protists to move and to engulf food. The movement is sometimes called amoeboid movement. Organisms that use this form of movement include Amoeba proteus.

All mammals have an embryo that develops with a placenta. Answers: True False

False

Which of the following is NOT characteristic of a fern? Answers: Ferns are quite small since they lack vascular tissue Fern sporophyte is vascular. Fern sporophyte leaves first appear in a curled-up form termed a fiddlehead. Fern sporophyte is the dominant generation in the fern life cycle

Ferns are quite small since they lack vascular tissue Response Feedback: In ferns, the dominant generation is the diploid sporophyte that produces sporangia; sites of meiosis that produce haploid spores. The spores give rise to a haploid, leaf-looking structure that does not contain vascular tissue called the thallus. On the thallus are antheridia, which produce sperm, and the archegonium, which produce eggs. Sperm swim to the archegonium and fuse to produce a diploid zygote that remains in the archegonium. The young sporophyte grows from the gametophyte and eventually gives rise to the mature sporophyte.

At one time, biologists thought that fungi were merely forms of plants that had lost their chlorophyll and had returned to saprotrophy to gain food. Why is this no longer considered a solid theory? Answers: Plants are multicellular and fungi are unicellular or multinucleated noncellular plasmodia. Plants store glycogen, while fungi store starch. Fungi attack and engulf food for internal digestion. Fungi have flagella at some stage, providing mobility that plants never have. Fungal cell walls contain chitin rather than cellulose.

Fungal cell walls contain chitin rather than cellulose. Response Feedback: Since plants and fungi have two different molecules that serve as the major structural component of their cells walls as well as two different methods of obtaining food, it is unlikely that one arose from the other.

What is the significance of the Miller-Urey experiment? Answers: It demonstrated that new cells can only come from pre-existing cells. It demonstrated that the monomers of life could have been formed from chemical processes in the absence of life. It created the hypothesis that membrane-like structures could form in the absence of life. It created the hypothesis that the atmosphere of the early earth had a lot of oxygen.

It demonstrated that the monomers of life could have been formed from chemical processes in the absence of life.

Who invented the term "virus"? Anton van Leeuwenhoek Harold Urey Stanley Miller Louis Pasteur

Louis Pasteur

Euglena Answers: is an excavate. is an chromalveolate. has an eyespot. all of the above are true. Only A and C are true.

Only A and C are true.

Which of the following statements is NOT correct about cnidaria? Answers: A jellylike mesoglea contains cells that form a nerve net throughout the body. There are two tissue layers: an outer epidermis and inner gastrodermis. Stinging cells contain a threadlike nematocyst released to capture prey. The adult body is bilaterally symmetrical.

The adult body is bilaterally symmetrical. Response Feedback: Cnidaria all have radial symmetry.

Which statement is NOT true about ferns? Answers: The sporophyte stage lacks vascular tissue. Fertilization requires moisture for the sperm to swim to the egg within the archegonia. The sporophyte stage is the dominant generation. Antheridia and archegonia develop on the prothallus of the gametophyte stage.

The sporophyte stage lacks vascular tissue. Response Feedback: In ferns, the dominant generation is the diploid sporophyte that produces sporangia, sites of meiosis that produce haploid spores. The spores give rise to a haploid gametophyte, a leaf-looking structure that does not contain vascular tissue, called the thallus. On the thallus are antheridia, which produce sperm, and the archegonium, which produce eggs; the sperm require water to swim to the archegonium and fuse to produce a diploid zygote, which remains in the archegonium. The young sporophyte grows from the gametophyte and eventually gives rise to the mature sporophyte. The mature sporophyte is a vascular plant with true roots, leaves, and stems.

Which statement is true about bacteria? Answers: They usually lack a cell wall. They lack ribosomes. They contain a single, circular DNA molecule as the genetic material. They contain a nucleus.

They contain a single, circular DNA molecule as the genetic material. Response Feedback: Bacteria are single-celled organisms; they do not have any membrane-bound organelles, but they do contain ribosomes which are not membrane bound. Their DNA is a single circular chromosome that is located in the cytoplasm of the cell, not in a nucleus. Bacteria are found in one of three shapes: bacilli (rod), cocci (spheres), and spirillum (curved). They reproduce asexually through binary fission.

Which of the following is NOT true about viruses? Answers: They contain nucleic acid, protein, and mitochondria. The genome may be DNA or RNA. They exhibit host specificity. They are obligate intracellular parasites.

They contain nucleic acid, protein, and mitochondria. Response Feedback: Viruses are segments of either DNA or RNA enclosed in a capsid composed of protein and possibly a membrane called an envelope. The genetic material of the virus may be either DNA, which can be single stranded or double stranded, or RNA, which can be single stranded or double stranded. They cannot exist without a host who supplies the molecular machinery to produce more viral genetic material, proteins for the capsid, and the envelope. Viruses do not have the structures necessary to be considered cellular; nor are they considered living.

Earthworms are Answers: arthropods. annelids. platyhelminthes. molluscs.

annelids Response Feedback: Annelida include earthworms and are segmented with a hydrostatic skeleton and a closed circulatory system. Molluscs include clams, snails, and squids and all have a foot, mantle, and visceral mass. Echinoderms include star fish and are characterized by a water vascular system and a thin epidermis covering an endoskeleton of calcareous plates. Platyhelminthes are flatworms like tapeworms and flukes. Arthropoda includes crustaceans, insects, and spiders and are characterized by an exoskeleton, an open circulatory system, and well-developed sensory organs.

Lichens Answers: are a symbiotic relationship between an alga and fungus. are important in making bread. thrive in areas of high pollution. cause the flavors in blue cheese.

are a symbiotic relationship between an alga and fungus.

Diatoms Answers: are unicellular algae with glassy cell walls. have pseudopodia. are excavates. all of the above are true. Only A and B are true.

are unicellular algae with glassy cell walls.

Which type of organism is characterized by having jointed appendages, ability to molt, and three sets of fused segments? Answers: chordates arthropods molluscs annelids

arthropods Response Feedback: Arthropods are covered in a rigid exoskeleton and must molt to increase in size. They have fused segments with a pair of jointed legs for every segment.

Which stage of viral reproduction takes place when the spikes of the virus bind to a specific receptor molecule on the surface of a host cell? Answers: release stage biosynthesis stage penetration stage attachment stage

attachment stage Response Feedback: During attachment, the virus binds to a specific receptor protein on the surface of the cell. Although the receptor has some function that it normally performs for the cell, the virus is able to use the receptor for its own purposes. It then fuses its envelope with the membrane of the cell, allowing the capsid and its contents to enter the cell.

Which of the following features is NOT a characteristic used to distinguish birds? Answers: hard-shelled egg air sacs body temperature that varies with environment four-chambered heart feathers

body temperature that varies with the environment Response Feedback: Birds are endotherms so they do not have a variable body temperature but rather maintain a specific temperature through metabolic processes.

Look at the phylogenetic tree above. Which of the following organisms are in the Bilateria? Answers: hydra butterflies sponges corals cnidarians earthworms sea stars snails

butterflies earthworms sea stars snails

Which of these is the most accurate description of a virus? Answers: chemical complexes of RNA or DNA protected by protein a cell at the boundary between living and nonliving things a noncellular living organism one of the smallest bacteria known

chemical complexes of RNA or DNA protected by protein Response Feedback: Viruses are segments of either DNA or RNA enclosed in a capsid composed of protein and possibly a membrane called an envelope. They are generally smaller than the smallest known bacteria and are obligate parasites, meaning that they cannot exist without a host, whose host supplies the molecular machinery to produce more viral genetic material, proteins for the capsid, and the envelope.

Fungi are NOT photosynthetic because they lack Answers: cell membrane. xylem. chloroplasts. cell walls.

chloroplasts Response Feedback: Fungi do not contain chloroplasts which contain the photosynthetic pigment chlorophyll. This molecule allows autotrophs to convert the energy of the sun into chemical potential energy in the form of organic molecules.

One bacterial cell passes DNA to a second cell through a sex pilus in the process of Answers: transduction. transformation. conjugation. replication.

conjugation Response Feedback: Of the three possible methods of DNA transfer for bacteria, the only one that involves a movement of DNA directly from one bacterium to another is conjugation.

Which is an example of an alga? Answers: amoebae diatoms slime molds ciliates

diatoms Response Feedback: The algae include green algae, diatoms, dinoflagellates, red algae, and brown algae. Sporozoa, zooflagellates, slime molds, and ciliates are protists but fall under other classifications than algae.

Cyanobacteria Answers: have a nucleus and chloroplast. split hydrogen sulfide. are heterotrophs. do photosynthesis similar to green plants.

do photosynthesis similar to green plants.

The molluscs look so different, and yet we can tell they are related because they all Answers: have a mantle, visceral mass, and a foot. have shells. have an external skeleton. are segmented.

have a mantle, visceral mass, and a foot Response Feedback: All molluscs have three characteristics: 1) a visceral mass that is the soft-bodied portion that contains the organs; 2) a strong, muscular foot used for locomotion; and 3) the mantle, a covering that partially covers the visceral mass and secretes a shell if one is present.

Which of the following apply to the crab in the image? Answers: exoskeleton crustacean molts to grow gastropod arthropod insect echinoderm arachnid

exoskeleton crustacean molts to grow arthropod

Jaws are believed to have evolved from the Answers: cranium. first pair of gill arches. suckers of lampreys. first ribs.

first pair of gill arches. Response Feedback: The first pair of gill arches (skeletal rods that support the gill slits) are thought to have become modified so that they became a hinged jaw. The second pair of gill arches also became modified and evolved into support structures for the jaw.

Molds (except slime and water molds) and mushrooms belong to the kingdom Answers: Animalia. Plantae. Fungi. Protists.

fungi Response Feedback: Molds and mushrooms are both part of the kingdom Fungi. Archaea is composed of prokaryotic organisms that are closely related to eukaryotes. Protists are typically unicellular eukaryotes and do contain water and slime molds, which are not classified as fungi because they have cellulose in their cell walls and engulf their food, unlike fungi which digest outside their bodies. Unlike plants, molds and mushrooms do not contain chlorophyll.

In the above image the ovary is labeled Answers: g c a e

g

Which sequence is correct in the life cycle of alternation of generations? Answers: gametophyte → gametes → zygote → sporophyte → spores gametophyte → gametes → zygote → spores → sporophyte gametophyte → spores → gametes → zygote → sporophyte gametophyte → gametes → spores → sporophyte

gametophyte → gametes → zygote → sporophyte → spores Response Feedback: Plants undergo a cycle called alternation of generations that alternate between multicellular haploid and diploid organisms. The haploid generation is called the gametophyte and produces gametes; the gametes fuse and give rise to a diploid generation called the sporophyte. The sporophyte has structures that undergo meiosis and produces spores that are haploid and give rise to the sporophyte generation.

Defining characteristics of chordates are Answers: gill arches or pharyngeal pouches, dorsal tubular nerve cord, notochord, and postanal tail. segmentation, dorsal hollow nerve cord, gill arches or pharyngeal pouches. dorsal hollow nerve cord, notochord, bilateral symmetry, and postanal tail. bilateral symmetry, segmentation, and well-developed coelom

gill arches or pharyngeal pouches, dorsal tubular nerve cord, notochord, and postanal tail. Response Feedback: There are four characteristics that an organism must have at some point in this life history to be classified as a chordate. These are 1) a notochord or dorsally located support rod; 2) a dorsally located nerve cord that is filled with fluid; 3) pharyngeal pouches, these can give rise to gills or can be adapted for other uses; and 4) a postanal tail.

The ____ algae are thought to be closely related to the first plants because they share most of the characteristics of plants. Answers: red brown pink green

green Response Feedback: Green algae are thought to be the most closely related to plants because they share these characteristics: a cell wall composed of cellulose; chlorophylls a and b; and the storage of starch as a reserve energy source.

The plant in the image is a Answers: nonvascular plant. seedless vascular plant. angiosperm. gymnosperm.

gymnosperm

The chief distinguishing characteristic of all mammals is the presence of Answers: four limbs. a four-chambered heart. hair and mammary glands. constant internal temperature.

hair and mammary glands Response Feedback: Mammals and birds both have a four-chambered heart and maintain a constant body temperature. Mammals, amphibians, birds, and some reptiles all have four limbs. Some but not all mammals have a placenta that supplies the fetus with nutrients and removes wastes.

Which of the following sequences correctly represents vertebrate evolution? Answers: jawless fish - lobe-finned fish - amphibians - reptiles - mammals jawless fish - amphibians - reptiles - lobe-finned fish - mammals lobe-finned fish - mammals - reptiles - jawless fish - amphibians lobe-finned fish - reptiles - mammals - jawless fish - amphibians

jawless fish - lobe-finned fish - amphibians - reptiles - mammals Response Feedback: Jawless fish and all of the other classes have vertebra, the first derived trait. Lobe-finned fish, amphibians, reptiles, and mammals all have lungs. Amphibians, reptiles, and mammals all are tetrapods; they have true limbs. Reptiles and mammals (as well as birds, or feathered reptiles) have amniotic eggs; in conjunction with internal fertilization, the amniotic egg allows these classes to reproduce without the necessity of water to protect and support the egg. Mammals further have the characteristic of producing milk from mammary glands to nourish offspring once they are born.

The cartilaginous fishes include all EXCEPT Answers: dogfish shark. lampreys. skates. whale shark. rays.

lampreys Response Feedback: Cartilaginous fish, class Chondrichthyes, do not have bony skeletons; of the fish listed, sharks, rays, and skates all belong to this class. Lampreys do not have a skeleton so they are not part of this class but, because they are jawless, they belong to the class Petromyzontida.

Which of the following is NOT a characteristic of echinoderms? Answers: endoskeleton of spiny, calcium-rich plates locomotion by muscles both sexual and asexual reproduction larva is bilaterally symmetrical

locomotion by muscles Response Feedback: Echinoderms do not use muscles to move; most are slow moving or sessile. The echinoderms, such as sea stars and sea urchins, which do move, do so by means of tube feet. Tube feet work by means of forcing water into the ampulla and a podium (foot portion). The ampulla squeezes water into the podium, causing it to expand. When the foot comes into contact with a surface, the center withdraws, giving the foot suction and causing it to adhere to the surface. The organism can move along slowly by expanding and contracting the tube feet.

Which of the following is a nonvascular plant that has the longest evolutionary history on land? Answers: ferns redwood tree bristlecone pine tree moss

moss Response Feedback: Ferns, pine trees, redwood trees, and grass are all vascular plants. Mosses are nonvascular plants; they do not have true leaves, true roots, or stems.

Which of the following apply to the sponge in the image? Answers: cnidarian no true tissues fungus cnidocytes asymmetrical radial symmetry animal skeleton with spicules or protein spongin

no true tissues asymmetrical animal skeleton with spicules or protein spongin

The plant in the image with a dominant, very small gametophyte is a Answers: seedless vascular plant. angiosperm. nonvascular plant. gymnosperm.

nonvascular plant

What is the correct evolutionary pathway for the key features of chordates? Answers: notochord - vertebrae - jaws - bony skeleton - lungs - amniotic egg - 4 limbs - mammary glands vertebrae - notochord- jaws - bony skeleton - lungs - 4 limbs - amniotic egg - mammary glands notochord - vertebrae - jaws - bony skeleton - mammary glands - lungs - 4 limbs - amniotic egg notochord - vertebrae - jaws - bony skeleton - lungs - 4 limbs - amniotic egg - mammary glands

notochord - vertebrae - jaws - bony skeleton - lungs - 4 limbs - amniotic egg - mammary glands Response Feedback: The first feature to evolve was the presence of a notochord. The notochord is then replaced by the vertebrae. The evolution of jaws enabled chordates to feed on different food choices. A bony skeleton increased the efficiency of movement. Lungs increased respiration. Four limbs would provide greater support on land. An amniotic egg protected the embryo from drying out on land. Mammary glands increase the nutrition available for the offspring.

Ovules are contained within the Answers: stigma. style. filament. ovary. anther.

ovary Response Feedback: The carpel, or pistil, of a flower is the female part of the flower and is made up of the stigma, style, and the ovary that contains the ovule.

Botanically, a seed is a structure developed from a(n) Answers: ovule. anther. stigma. sepal. style.

ovule Response Feedback: A seed is a mature ovule containing a sporophyte. The stigma is the sticky end of a carpel where pollen is trapped and the style is the tube that connects the stigma to the ovule.

Which of the following kinds of molecules is thought to have been absent from the primitive reducing atmosphere? Answers: hydrogen (H2) methane (CH4) water vapor (H2O) oxygen (O2)

oxygen (O2) Response Feedback: In the early earth, volcanoes erupted constantly, and the first atmospheric gases would have consequently contained methane (CH4), ammonia (NH3), hydrogen (H2), and water vapor. Oxygen (O2) would not have been present until photosynthetic organisms had evolved and produced oxygen that collected in the atmosphere.

Microbiology is the study of microbes. These include all but which of the following? Answers: Bacteria Archaea viruses plants

plants Response Feedback: All of the listed organisms, except plants, fall into the category of microbes. Most of these are small enough that a microscope to see them, although that is not true in all cases.

This is a question with multiple correct answers. Choose all that are correct. You will receive points for each correct answer and lose for each incorrect. You will not get negative points on the question. Which of the following apply to the anemone in the image? Answers: polyp cnidocytes bilateral symmetry fungus arthropod cnidarian medusa radial symmetry

polyp cnidocytes cnidarian radial symmetry

Bovine spongiform encephalopathy (BSE), or "mad cow disease," is caused by a(n) Answers: archeon. bacterium. cyanobacterium. prion. virus.

prion Response Feedback: One form of infectious protein or prion is bovine spongiform encephalopathy (BSE), or "mad cow disease."

The capsid of a virus is composed of Answers: protein. DNA. lipid. cellulose. RNA.

protein Response Feedback: The capsid of a virus may take one of several shapes and is composed of protein subunits.

Which type of animal symmetry produces mirror images of each other no matter how the animal is sliced longitudinally? Answers: asymmetrical symmetry asymmetrical symmetry and bilateral symmetry bilateral symmetry radial symmetry

radial symmetry Response Feedback: Radial symmetry means that the animal is organized circularly, so that no matter how the animal is sliced longitudinally it produces mirror images. Asymmetrical symmetry means that they have no particular symmetry. Bilateral symmetry means that the animal has definite right and left halves. The only cut that produces a mirror image is down the center of the animal.

____ are organisms that break down dead organic matter in order to absorb the nutrient molecules. Answers: Saprotrophs Parasites Heterotrophs Eukaryotes

saprotrophs Response Feedback: Organisms can be classified by the way that they obtain food; heterotrophs are organisms that ingest matter as a food source, parasites spend all or part of their lives feeding off of a host and saprotrophs digest food outside their bodies, allowing any unused nutrients to be used by autotrophs, who convert inorganic energy into an organic molecule.

When an enveloped animal virus enters a cell during the entry stage, Answers: the envelope is removed after the virus is inside the cell's nucleus. it immediately integrates its nucleic acid genome into the host chromosomes. the next thing it does is assemble a new virus. the protein capsid is removed through uncoating to expose the viral genome.

the protein capsid is removed through uncoating to expose the viral genome. Response Feedback: Attachment is the first stage where the virus attaches to a receptor protein on the host cell. Entry is the next stage and denotes when the virus actually enters the host cell. Once the virus has entered the cell, uncoating of the virus proceeds and the viral genetic material as well as the capsid and other viral components are deposited in the cell.

The term deuterostome refers to Answers: having a spiny skin. having three germ layers. the second embryonic opening becoming the mouth. possessing a notochord.

the second embryonic opening becoming the mouth Response Feedback: The term deuterostome is from the Greek, "deuteros," meaning "second" and "stoma," meaning "mouth"; so the term refers to the formation of the mouth from the second opening. A deuterostome is a developmental stage where the second embryonic opening becomes the mouth and an outpocketing by the primitive gut becomes the coelom.

Which difference distinguishes protostomes from deuterostomes? Answers: One has a nervous system, and one doesn't. One has cephalization and one doesn't. One has a notochord and one doesn't. Their embryonic development is different.

their embryonic development is different Response Feedback: There are two developmental plans: protostomes or deuterostomes. During the embryonic development of protostomes the mouth develops from the blastopore and in deuterostomes the anus develops from the blastopore

Which features set most of the members of protista apart from the rest of the kingdoms? Answers: photosynthetic and unicellular None of the answer choices is correct. multicellular and microscopic unicellular and microscopic

unicellular and microscopic Response Feedback: Protists are often unicellular and microscopic. While some of them are photosynthetic, heterotrophic, and even multicellular these are not traits unique to the protists. Animals, plants, and fungi all share some of these traits as well.