exam4 quiz review

When did amphibians evolve?

350 million years ago

Compare a pseudocoelom to a coelom.

A coelom is completely enclosed by mesoderm whereas a pseudocoelom has an outer covering of mesoderm and an inner one of endoderm.

Birds are thought to have evolved from small feathered dinosaurs. Evidence for this comes from the fossil discoveries of ______________________ and ____________________, two transitional forms between dinosaurs and birds.

Archaeopteryx; Caudipteryx

Which of the following lists the organization of a mammalian body from least to most complex?

Cell—tissue—organ—organ system

Which of the following would NOT be an example of negative feedback control in homeostasis?

During the birth process, stretch receptors in the uterus stimulate the release of oxytocin from the pituitary gland. This hormone stimulates uterine muscle contraction that increases stimulation of the stretch receptors.

If a mutation occurred in a flatworm such that the flame cells no longer functioned, what do you predict would be the consequence?

Excretory function would be impaired

Germ layers are

Germ layers are

Attribute one of these statements to the blastopore.

It occurs in both protostomes and deuterostomes.

Characterize the life cycle of cnidarians.

Some have only polyps, some have both polyps and medusae, and others have medusae and a reduced polyp stage.

Which of the following correctly describes the fate of the embryonic germ layers?

The endoderm forms the gut, the ectoderm forms the epidermis and parts of the nervous system, and the mesoderm forms muscles and most internal organs.

How does an open circulatory system differ from a closed one?

The open circulatory system has a combination of blood vessels and large thin-walled sinuses whereas a closed circulatory system has only vessels

Forelimbs form at the junction of the neck and thoracic vertebrae, the position of which is controlled by HoxC-6 genes. Several kinds of vertebrates from different classes are limbless, including limbless lizards, and amphibians known as caecilians. All descended from limbed forms. On the basis of recent research in genetics, what would you conclude about the functioning of their HoxC-6 genes?

The site of expression of their HoxC-6 genes may have moved anteriorly until the level of expression has eliminated the neck region.

Bilateria are characterized by

a plane of symmetry that forms mirror images around a vertical plane in the midline.

Hominins are

all forms of humans, extinct and extant.

coelomates are

animals that have a true coelom

Which of the following are the closest ancestors of humans (genus Homo)?

australopithecines

In Earth's history, what might the cooling of the Earth and the resulting change from a forested to a grassy landscape have made adaptive in humans?

bipedalism

The nearest living relatives of crocodiles and alligators are

birds

The outcome of cleavage during embryonic development is the production of a

blastula

The process by which cells acquire specialized forms and functions is called

cell differentiation

Metamorphosis is

changing of one body form to another within a species, such as the change from an aquatic tadpole to a terrestrial frog.

The stage of development that involves cell division without cell growth is

cleavage

The recent reassessment of animal classification is the result of

comparisons of dna and r Rna among different taxa

The change of a larval form of insect to a different adult form is known as

complete metamorphosis

Cephalization is

concentration of the sensory organs on the anterior end of the body.

Collagen is a tough, stretch-resistant protein. You would be most likely to find collagen in which tissue type?

connective

You are presented with a newly discovered invertebrate species. As you observe it in your lab, you note that the animals shed their skin. Which designation might this lead you to consider?

ecdysozoa

Germ layers An organism in your lab has issues with a malformed central nervous system that can be traced all the way back to the embryonic stage. To further investigate this issue, which germ layer would you want to examine closely to get an idea of exactly how the malformation occurred?

ectoderm

The human body's arterial blood pH is tightly maintained around 7.4 by buffering agents that bind hydrogen ions to stop any change in pH. If an acid-base imbalance overcomes the buffer system, the body changes the ventilation rate, or the rate at which gas enters or leaves the lungs. Changing the ventilation rate changes the concentration of CO2 in the blood, which alters the pH of the blood. In this case, the muscles that control the ventilation rate are acting as the:

effector

The process by which a fertilized egg becomes a distinct organism is called

embyronic development

Animals capable of producing their own body heat by way of metabolism and of retaining it are said to be

endothermic

t or f: A disadvantage in possessing a cuticle is that it forces fertilization to be external

false

t or f: Partitions isolate each segment so each must contract or expand in unison.

false

t or f: The endoderm is a germ cell layer that tends to cover the embryo.

false

t or f: The epidermis, mesoglea, and gastrodermis represent the triploblastic condition found in all cnidarians

false

t or f: The nervous system of a cnidarian consists of a central ganglion leading into a nerve net. True

false

t or f:Choanoflagellates are similar to the choanocytes that corals possess.

false

t or f:Cnidarians can detect and react to prey using a centralized nervous system.

false

t or f:Each arm of the starfish differs internally, one being specialized for reproduction, another for respiration, a third for digestion, a fourth for the water vascular system, and the fifth for the nervous and circulatory systems.

false

t or f:Homeostasis refers to the property of maintaining particular physiological variables such as body temperature and solute concentrations absolutely constant.

false

t or f:Redundancy in segmented animals is not an advantage.

false

t or f:The cuticle is porous and the diffusion of respiratory gases, even through the thickest areas, is not a problem

false

t or f:The two body forms of some Radiata is an example of alternation of generations.

false

t or f:stem cells have determinate cleavage

false

What unique trait do bats have that no other mammal has?

flight

An acoelomate is an animal that

has neither a coelom nor a pseudocoelom.

Triploblastic are animals that

have 3 germ layers

Birds are different from all other living vertebrates because they

have feathers

It's your birthday and you splurge with a big slice of chocolate cake, heavy on the icing. Shortly afterwards, your blood glucose levels rise until an endocrine mechanism (secretion of insulin) counteracts this rise and glucose levels decline. The initial change in blood glucose and insulin response that follows is an example of: positive feedback.

homeostasis

Animals that lack a vertebral column are known as

invertebrates

You are given an embryo with eight cells and you carefully separate them and allow them to develop in separate containers. Each of the cells forms a complete embryo that develops normally into an adult animal. How would you categorize your animal?

it has indeterminate cleavage

Which of the following traits are possessed by amphibians but are not present in fish?

limbs

Eutherian mammals are uniquely defined by

longer gestation periods because of more highly developed placentas.

Which major tissue type exhibits the shortening of its cells (i.e., contraction) as a major function?

muscle

Which of the following tissue types is specialized to conduct electrical signals?

nervous

Connective tissue serves to support and bind other tissues. Which of the following is NOT an example of connective tissue?

neurons

In negative feedback, the variable being regulated is changed in the _______ direction, while in positive feedback the variable is changed in the ________ direction.

opposite, same

The release of factors by cells that influence the activity of nearby cells is referred to as:

paracrine signaling

Adult echinoderms display __________ symmetry; however, their larvae display ____________ symmetry. biradial; radial

pentaradial; bilateral

In invertebrates with open circulatory systems, hemolymph is composed of:

plasma plus interstitial fluid

If you conducted an experiment in which you took a complete animal that had no germ layers and strained it through a fine-mesh cloth so that all its cells separated, then you placed all the cells together and they reunited to form a new animal, to which phylum would that animal likely belong? (This was an actual experiment.)

porifera

Germ layers An organism in your lab has issues with a malformed central nervous system that can be traced all the way back to the embryonic stage. To further investigate this issue, which germ layer would you want to examine closely to get an idea of exactly how the malformation occurred?

radial cleavage

An animal that is attached to the substrate and cannot move from one place to another is said to be

sessile

Most cnidarians possess two distinct body forms: the polyp, which is ___________, and the medusa, which is ___________.

sessile; motile

The human body's arterial blood pH is tightly maintained around 7.4 by buffering agents that bind hydrogen ions to stop any change in pH. If an acid-base imbalance overcomes the buffer system, the body changes the ventilation rate, or the rate at which gas enters or leaves the lungs. Changing the ventilation rate changes the concentration of CO2 in the blood, which alters the pH of the blood. In this case, pH 7.4 is the:

set point

During the Cambrian Explosion, the evolution of Hox genes is thought to have assisted rapid speciation because ______ changes in the expression of Hox genes lead to ______ variation among certain important morphological traits.

simple; large

The process of maintaining a _________ internal environment despite changes in the external environment is known as ________.

stable; homeostasis

The choanocytes have a flagellum that moves water through the sponge and a collar that extracts food particles from the water. In what group have you encountered very similar cells before?

the choanoflagellates

What is a characteristic of most animals?

the have hox genes

In addition to the frog, what other organisms are classified as modern amphibians?

toad,salamanders

t or f: Locomotion is more efficient in segmented animals because individual segments can move semi-independently.

true

t or f:A hydrostatic skeleton has no bones or cartilage.

true

t or f:A positive feedback loop causes a self-amplifying cycle where a physiological change leads to even greater change in the same direction. True

true

t or f:Although a medusa and a polyp look different, they have similar body plans.

true

t or f:Bats are active at night, therefore having acute hearing assist the bat in finding food.

true

t or f:Cnidarians are able to capture prey by stinging them with microscopic harpoon-like projectiles released by special cells called nematocytes.

true

t or f:Cnidarians consume food brought inside the gastrovascular cavity using extracellular digestion.

true

t or f:Nematodes and arthropods utilize similar hormones in the molting process, suggesting that these two phyla are closely related within the Ecdysozoa

true

t or f:The animal kingdom is a monophyletic grouping.

true

t or f:The cuticle is a non-living cover that serves to both support and protect the animal.

true

t or f:The cuticle limits growth and must be periodically shed to allow a new larger cuticle to be formed.

true

t or f:cndarians can exhibit one of two life forms: a sessile polyp and/or a free-swimming medusa form

true

t or f:tktaalik is an important fossil for the understanding of phylogeny because it is an intermediate form between fish and amphibians. True

true

t or f: in segmented animals like earthworms (phylum Annelida), each segment may develop a nearly complete set of adult organ systems

truw

An organ must contain at least:

two different tissues types