Chapter 32 & 41
What is the process of asexual reproduction in sponges?
A sponge can break into fragments and each fragment can become an individual.
Which structural features common to connective tissue?
Abundant extracellular material Cells spaced widely apart
Please match each cnidarian class to the correct representatives of that class.
Anthozia-corals Hydrozoa- Portuguese man of war Scyphozoa- jellyfish Cubozoa- box jellies Staurozoa- star jellies
Why can't we base animal classification on whether or not an animal has a coelom?
Because the acoelomate and pseudocoelomate conditions have evolved multiple times
Select the key innovations in animal evolution.
Body cavity Segmentation Symmetry Tissues Various patterns of embryonic development
Which structures belong to the nervous system?
Brain Sense organs Spinal cord
What are the flagellated cells that line the internal cavity of a sponge and help water flow through the ostia called?
Choanocytes
Members of what phylum are characterized by a diploblastic, radially symmetrical body plan and, while not having organs and organ systems, possess distinct tissues?
Cnidaria
What has helped to resolve the relationships between most animal phyla?
Combining data from multiple genes
What is the primary function of nerve cells?
Conducting electrochemical signals
Which are the functions of epithelium?
Covering body surfaces Forming barriers between body compartments
Comb jellies make up the phylum
Ctenophora
Some individuals in the cnidarian class ___ have a sting that is toxic enough to kill humans.
Cubozoa
Protostomes can be divided into two clades
Ecdysozoa and Lophotrochozoa
What are antagonistic effectors?
Effectors that have opposing effects on the same variable.
What type of tissue forms membranes, together with connective tissues?
Epithelial
___ tissues are typically organized into one or more sheets of cells.
Epithelial
___ tissues line the surfaces of organs and body cavities.
Epithelial
What clade includes all animals that have true tissues and body symmetry?
Eumetazoa
Where are smooth muscles found in vertebrates?
In organs of the internal environment
Describe loose connective tissue
It consists of cells scattered within a matrix with a relatively large amount of ground substance.
Which of the following describes an animal that is a homeotherm?
It maintains its body temperature within a narrow range.
Which of the following are the two major clades of protostomes?
Lophotrochozoa Ecdysozoa
What is the source of body heat produced by animals?
Metabolic reactions
Choose the four levels of organization within the vertebrate body.
Organ systems Cells Tissues Organs
Which organ system produces gametes?
Reproductive
Describe the composition of cardiac muscle
Small interconnected cells
Choose the statement that most accurately describes the presence of tissues in animals.
Specialized tissues are found in all animals except sponges.
Which of the following statement best describes sponges?
Sponges have several types of cells that perform different functions.
What are the types of muscle tissue?
Striated Smooth Cardiac
What accurately describes animals with a segmented body plan?
The animal's body is divided into nearly identical units.
What is countercurrent heat exchange?
The transfer of heat from warm blood to cold blood that is being returned to the body's core.
What are characteristics of cnidarians?
They are made of distinct tissues. They have radial symmetry. They are diploblastic.
Which of the following statements about sponges is true?
They are multicellular but do not have true tissues.
What are the features of muscle fibers?
They are tubular. They contain multiple nuclei.
Which of the following describes physiological variables?
They fluctuate around a mean within a certain, typically very narrow, range.
Why are noncoelomate invertebrates, such as sponges and jellyfish, and noncoelomate worms, evolutionarily important?
They possessed the basic animal body plan from which the body plan of all other animals evolved.
What best explains why animals are considered monophyletic?
They share features of major importance.
What is true regarding molecular and traditional analysis of phylogenies?
Though there are differences between the two phylogenies, there is much agreement in the deep parts of the evolutionary tree.
What is the function of neuroglia?
To support and protect neurons
Traditional views of animal phylogeny have depended on features of ___ and embryological development.
anatomy
Animals that lack a coelom do not form a monophyletic clade; therefore,
animal classification cannot be based on whether or not an animal has a coelom
Insulin stimulates responses that lower blood glucose, and glucagon stimulates responses that raise blood glucose, so they are
antagonistic effectors.
Sponges can reproduce ___ simply by breaking into fragments, each of which continues to grow as a new individual.
asexually
Most sponges are
asymmetrical
This group of animals is characterized by a transition to bilateral symmetry.
bilateral
Dilation and constriction of ___ vessels near the skin surface affect heat loss from the body.
blood
The special connective tissues are ___ ,___ ,___ and
blood bone cartilage
Which type of muscle is composed of small, interconnected cells joined by intercalated disks?
cardiac
What are the special connective tissues?
cartilage, bone, blood
The five key innovations in animal evolution include tissues, a body ___ , various patterns of embryonic development, segmentation, and ___
cavity symmetry
Rank the following components of an organ system in order of increasing complexity. List the most simple structure at the top.
cell tissue organ organ system
The brain and spinal cord belong to the ___ system.
central nervous
The flagellated cells that line the internal cavity of a sponge and help water flow through the ostia are known as
choanocytes
As their name implies, flatworms in the phylum Acoela lack
coelom
What organisms are included in the phylum Ctenophora?
comb jellies
In ___ heat exchange, heat from warm blood is transferred by conduction to cold blood that is being returned to an animal's core.
countercurrent
Advantages of a body cavity include
cushioning internal organs. circulating materials. fostering developmental interactions.
As an animal's temperature decreases, the rates at which the molecules in its body move and encounter each other
decreases
Based on ample evidence, the echinoderms and chordates form a monophyletic clade called the
deuterostomes
The ___ and ___ systems obtain nutrients and oxygen for the body, while the circulatory system distributes those to every cell.
digestive respiratory
Which phyla contain Deuterostomes?
echinoderms and chordates
In contrast to Parazoa, the ___ includes all animals that have true tissues and body symmetry.
eumetazoa
Connective tissue cells are widely spaced apart, which allows for abundant ___ material.
extracellular
True or false: If the body is maintaining homeostasis, the internal environment is perfectly constant.
false
Because they obtain energy and organic molecules by ingesting other organisms, animals are
heterotrophs
A high metabolic rate is likely to result in
high body temperature
A(n) ___ is an animal that maintains its body temperature within a narrow range.
homeotherm
The ___ system produces cells that protect us against invading organisms while the ___ system is the first line of defense against pathogens and forms a protective covering.
immune integumentary
The organ systems that are responsible for protecting the body against attackers and invaders are the ___ and ___ systems.
immune integumentary
Dilation of ___ blood vessels blood flow, and constriction of blood vessels ___ blood flow.
increases decreases
How does a heterotrophic organism obtain energy and organic molecules?
ingestions of other organisms
The ___ system forms the outer covering of the body and is the first line of defense against disease-causing agents.
integumentary
Unlike the digestive cavity, the body cavity is
isolated from the exterior of the body.
All animals share features of major importance and are therefore
monophyletic
Protostomes are animals in which the embryonic blastopore becomes the
mouth
A positive feedback loop, when presented with a change in a physiological variable, results in responses that
move the variable further in the direction of the change.
The ___ system consists of two interrelated systems. It provides physical support for the body and moves it.
musculoskeletal
In ___ feedback, biochemical reactions help to keep a variable near its set point.
negative
What is the term for a homeostatic mechanism in which deviations from the set point are minimized?
negative feedback
The primary function of ___ tissue is to produce and conduct electrochemical signals.
nerve
The sensory systems are a subset of the ___ system.
nervous
Cells that support, protect, and aid in the nourishment of neurons are called
neuroglia
Despite their simplicity, the appearance of noncoelomate invertebrates was very important - these organisms possessed the basic animal body ___ , from which that of all other animals evolved.
plan
In general, what does not maintain homeostasis because the result is magnification, rather than minimization, of fluctuations in physiological variables?
postive
Organs are made of up of tissues that are:
present in up to several different types.
Animals that undergo embryonic development where the embryonic blastopore develops to become the animal's mouth are
protostomes
Temperature affects the ___ of chemical reactions.
rate
The ___ system is responsible for producing gametes and nurturing the developing embryo and fetus.
reproductive
What is a type of body plan in which an animal's body is divided into nearly identical units?
segmented body plan
Organs are
self-contained. outlined by distinct borders.
Multinucleated muscle fibers are formed during development when
several cells fuse, end to end.
Epithelial tissues are organized as one or more ___ of densely packed epithelial cells.
sheets
The three types of muscle tissue are: ___ muscle, ___ muscle, and ___ muscle.
skeletal smooth cardiac
Which organ systems support and move the body?
skeletal and muscular
All animals exhibit some form of body symmetry except
sponges
The only animals that lack any form of body symmetry are
sponges
In all animals except ____, cells differentiate into specialized ___ which are groups of cells that take on particular functions in the animal's body.
sponges tissues
Most sponges do not have a definite ___ and do not posses tissues.
symmetry
The mouth of an acoel flatworm leads to digestive
syncytium
A(n) ___ is formed by specialized cells of a single type that are organized to perform a particular function.
tissue
___ are clusters of specialized cells of a single given type
tissues
A reduction in an endothermic animal's internal body temperature to produce a state of dormancy is called
torpor
___ is a state of dormancy characterized by a reduction in an animal's metabolic rate and body temperature.
torpor
How many clades does the Bilateria comprise?
two
The regulation of the concentration of body fluids is carried out by the ___ system.
urinary
In vertebrates smooth muscle is found in the organs of the internal environment, so it is also called ___ muscle.
visceral
n vertebrates smooth muscle is found in the organs of the internal environment, so it is also called ___ muscle.
visceral