Exam 3 Flashcards
what are traits of true sponges?
lack true tissues, can regenerate, filter feeders, sedentary
Cnidarians differ from sponges in that cnidarians have…
true tissues, motile forms, and tentacles
What is most consistent with the hypothesis that the cambrian explosion was caused by the rise of predator-prey relationship?
increased incidence of hard parts in the fossil record
What are characteristics of the body cavity?
acts as a hydrostatic skeleton in soft bodied animals, cushions suspended organs and preventing internal injury, a space lined by mesoderm in coelomates, allows internal organs to enlarge and move independently of the outer body wall
What is true about the animal tissues that develop from embryonic germ layers?
a pseudocoelom has the same functions as a true coelom, in a coelomate the tissue lining the inner side of the body cavity arises from the same germ layer as the tissue lining the outer side of the body cavity, and a diploblast has no mesoderm
what is NOT a characteristic of all animals?
they have tissues, organs, and organ systems
The animal phylum most like the protists that gave rise to the animal kingdom is _____.
porifera
Which of the following is a characteristic of cnidarians?
gastrovascular cavity
The earliest ancestors of about half of all extant animal phyla can be traced back to the ______ explosion
cambrian
An important trend in animal evolution was cephalization. An animals said to show cephalization when it_____
has an aggregation of sensory neurons at the anterior end
Members of the phylum Mollusca_____
are soft-bodied and often covered by a shell
what is thought to be most closely related to humans?
sea stars
What are NOT diagnostic features of the Chordata? a hollow dorsal nerve cord vertebrae muscular, post-anal tail notochord pharyngeal slits or clefts
vertebrae
The diagnostic feature of Chondrichthyes is ______
an endoskeleton of calcified cartilage
Most members of which group are most closely associated with wet or moist environment?
amphibians
what characteristic only of truly terrestrial animals with no need to return to water at any stage of the life cycle?
amniotic egg
There are three major groups of mammals, categorized on the basis of their _______
method of reproduction
Which chordate group lacks a post-anal tail and a notochord as adults?
tunicates
The common ancestor of all these chordate groups EXCEPT the \_\_\_\_ probably had paired appendages mammals amphibians lampreys ray-finned fishes reptiles
lampreys
What is the only chordate group that has hair?
mammals
what is the key difference between a coelom and a pseudocoelom?
only a coelom is fully lined with mesoderm tissue
A graduate student finds an organism in a pond and thinks it is a freshwater sponge. A postdoctoral student thinks it looks more like an aquatic fungus. How can they decide whether it is an animal or a fungus?
look for cell walls under a microscope
Gastrulation is the process that directly forms the _____
primary germ layers
Which of the following animals does NOT have a body cavity? flatworm clam nematode earthworm mouse
flatworm
During embryological development, the anus forms before the mouth in___
humans
Jaws evolved ______
by modification of the skeletal rods that previously supported the anterior pharyngeal gill slits
Which of the following clades contains the greatest number of animal species? chelicerats bilaterians sponges deuterosomes insects
bilaterians
what is thought to have let to the increasing complexity of the arthropod body plan?
changes in regulation of Hox genes for body segmentation
which of the following statements would be least acceptable to most zoologists?
a. the extant lancelets are contemporaries, not ancestors, , of vertebrates
b. the first fossils resembling lancelets appeared in the fossil record around 530 million years ago
c. recent work in molecular systematics supports the hypothesis that lanceletes are the basal clade of chordates
d. the extant lancelets are the immediate ancestors of the fishes
e. lancelets display the same method of swimming as do fishes
d. the extant lancelets are the immediate ancestors of the fishes
If the osteichthyan clade was exclusively made up of ray-finned and lobe-finned fish, the grouping would be…
paraphyletic
Why is a Tikataalik not classified as a tetrapod?
because it had gills
Complete metamorphosis, in which juveniles and adults are dissimilar, was also observed in insects. What is an advantage of metamorphosis?
adults and juveniles do not compete for the same food sources and adults and juveniles have different predatory pressures
All of the following are characteristics of members of the class Aves except one. Select the exception. Ectothermy No urinary bladder Bones lightened by numerous air spaces Feathers Lack of teeth
Ectothermy
what are functions of the hypothalamus?
synthesizes some hormones that are released into the blood vessels bound for another gland, integrates nervous and endocrine system, and synthesizes oxytocin and ADH
functions of the posterior pituitary
is an extension of the hypothalamus and releases oxytocin
functions of the anterior pituitary
synthesis and releases PRL, synthesizes an releases TSH, and regulated by hormones released into portal blood vessels
If surgical hypothyroidism would likely affect prolactin levels?
thyroid hormone levels decrease, TRH levels increase, and PRL levels increase
Which term describes a mechanism by which the internal conditions of an organism are kept at set values without regard to the external conditions? negative feedback conformational homeostasis thermoregulation regulatory homeostasis
regulatory homeostasis
Which of the following actions is not a function of the epithelium?
Creates an internal environment that is different from the external environment.
Allows the internal environment to alter its conditions to match those of the external environment.
Regulates the excretion of waste.
Controls the exchange of nutrients between the internal and external environments.
allow the internal environment to alter its conditions to match those of the external environment
True or False. Organisms must maintain homeostasis because optimal enzyme activity is achieved within a very narrow range of conditions
true
Which component of a homeostatic system sends instructions based on sensory information? sensor integrator set point effector
integrator
Which component of a homeostatic system perceives changes in some parameter of the environment? sensor integrator set point effector
sensor
Which of the following actions to warm a homeothermic body? shivering panting sweating dilating blood vessels
shivering
The four major categories of tissues are_____
nervous, epithelial, muscle, and connective
Homeostasis is the…
maintenance of a relatively constant and optimal internal environment
Negative feedback is a method of homeostatic control that____
ensures that conditions in an organism do not vary too much above or below their set points
A countercurrent heat exchanger enables an animal to ____
reduce the loss of body heat to the environment
Urine formed by a kidney collects in the _____ before being drained from the kidney by the _____ and transported to the _____
renal pelvis… ureter… urinary bladder
The _____ are the major blood vessels transporting blood to the kidneys.
renal arteries
The outer part of the kidney is the _____
cortex
what is the functional unit of the kidney?
nephron
Terrestrial animals are ___
osmoregulatory that must obtain water from the environment
Birds, insects, and many reptiles excrete nitrogenous waste in the form of uric acid, which ____
reduces water loss compared to other nitrogenous wastes, but requires more metabolic energy to produce
Freshwater fish excrete nitrogenous wastes as ____
ammonia
An appropriate group of animals to examine to observe a malpighian tubule would be _____
the insects
Osmoregulation and excretion are _____
mechanisms that maintain volume and composition of body fluids
What is the function of endocrine glands?
they release hormones into the bloodstream for distribution around the body
True or false? the homeostatic system fro blood calcium concentration is maintained by the hormones calcitonin and parathyroid hormone
true
Which of the following statements about the pituitary gland is false?
The anterior pituitary is connected to the hypothalamus by blood vessels
it produces hormones that control the menstrual cycle
the posterior portion is an extension of the hypothalamus
neurosecretory cells produce hormones that are stored in the anterior pituitary
Neurosecretory cells produce hormones that are stored in the anterior pituitary
True or false? The pancreas is responsible for producing hormones that maintain the homeostatic levels of glucose in the blood
true
How is the production of hormones such as thyroxin and estrogen regulated?
the hypothalamus directs the anterior pituitary to produce hormones that then stimulate or inhibit the production of these hormones
Which of the following statements about endocrine glands and the hormones they produce is true?
Antidiuretic hormone (ADH) produced by the anterior pituitary controls the body’s metabolic rate.
Erythropoietin (EPO) produced by the kidneys increases blood calcium levels.
Aldosterone produced by the adrenal glands controls the reabsorption of sodium ions by the kidneys.
Prolactin produced by the posterior pituitary triggers contractions in the uterus during labor.
aldosterone produced by the adrenal glands controls the reabsorption of sodium ions by the kidneys
Gigantism, a condition characterized by exceptionally rapid growth, is sometimes caused by a tumor that induces the gland in which it develops to overproduce a certain hormone. Where would such a tumor be expected to grow?
pituitary gland
In a physiological system operating with positive feedback, _______
a change in a variable will amplify rather than reverse the change
The hormone epinephrine causes opposite effects in two populations of target cells because _____.
each set of target cells has different receptor-transduction mechanisms
In their mechanism of action, a difference between lipid-soluble and water-soluble hormones is that____
lipid-soluble hormones bind to an intracellular receptor and this hormone-receptor complex binds to DNA
Oxytocin secretion and milk release from the mammary glands of lactating female mammals are initiated by ____
the physical sensation of the baby sucking at the nipple
Hormones are _____
chemical signals between cells, transported in blood or hemolymph
In general, how does a simple endocrine pathway differ from a neuroendocrine pathway? Type of feedback sensor secretions into the circulation target cells
sensor
When comparing two solutions that are separated by a selectively permeable membrane, the solution with the greater concentration of solutes is... hypoosmotic iso-osmotic hyperosmotic isotonic hypotonic
hyperosmotic
Many reptiles, including birds, excrete uric acid. What is an advantage of this trait in birds?
by minimizing water requirements, birds can reduce body weight
Fat soluble vitamins
A, D, E, K
water soluble vitamins
B1 and C
______ is absorbed from some foods like carrots in the form of carotene. The vitamin accumulates in the rods and cones of the eyes and plays a role in vision
vitamin A
The _______ are not involved as coenzymes. But they are still essential in our diet, and they are involved in important processes such as vision, bone formation, protection from oxidation, and blood clotting
fat-soluble vitamins
_______ is involved in the formation of hydroxyproline and hydroxylyxine, which are important amino acids and part of the collagen that forms the connective tissues. Lack of this vitamin causes scurvy, which can be prevented with citrus and other fruits.
vitamin C
______ is a vitamin that is used in reactions that transfer single-carbon units. The vitamin also helps reduce the risk of birth defects such as spina bifida and cleft lip. Women of child-bearing age should consume the recommended amount of this vitamin
folic acid
the ________ act as coenzymes in the body. They do not stay bonded to only one enzyme, but are used over and over again by different enzymes
water-soluble enzyme
when digested, proteins are broken down into ______
amino acids
when digested, fats are broken down into
glycerol and fatty acids
starch is a type of
polysaccharide
Your small intestine can absorb ____ without their being further digested.
fructoses
Which of these enzymes begins the breakdown of starch? bile disaccharides lipase amylase nucleases
amylase
Starch can be broken down into the disaccharide known as _____.
maltose
protein digestion begins in the
stomach
what is the main components of gastric juice?
water
_____ is secreted by the _____ and acts to emulsify _____ in the _____.
Bile … liver … fats … small intestine
What acid is responsible for stomach acidity?
hydrochloric acid
Which structure is not part of the alimentary canal?
salivary glands
Which process is not required for an animal to obtain energy from food?
excretion
True or false? One advantage of having a tube-like digestive tract is that digestion of all compounds can take place simultaneously down the tract.
false
True or False? The liver is a component of the alimentary canal.
false
Choose the correct statement from the list below.
Proteins that are consumed in the diet are absorbed as individual amino acids following digestion.
Mechanical digestion of proteins is more important than chemical digestion.
The stomach has a high pH which allows for the activation of digestive enzymes.
Protein digestion begins in the small intestine with the activation of trypsinogen to trypsin
Proteins that are consumed in the diet are absorbed as individual amino acids following digestion.
Choose the correct statement.
Carbohydrates are fully digested after passage through the stomach .
Carbohydrate digestion begins in the mouth with salivary amylase.
Carbohydrate absorption occurs primarily in the large intestine.
Bile salts from the gall bladder are essential to the digestion of carbohydrates.
Carbohydrate digestion begins in the mouth with salivary amylase.
Choose the correct statements.
Fats are fully digested after passage through the mouth and stomach.
Free fatty acid absorption occurs in the small intestine.
Fat digestion begins in the stomach with the activation of trypsinogen to trypsin.
Bile salts from the pancreas are essential to the digestion of fats
Free fatty acid absorption occurs in the small intestine.
Many people have a tendency to gorge on rich, fatty foods. How could such a preference have evolved?
In ancestral hunter-gatherer communities, individuals with a tendency to gorge on such foods when available would have had a selective advantage.
The mammalian trachea and esophagus both connect to the
pharynx
Which of the following organs is incorrectly paired with its function? stomach--protein digestion pancreas--enzyme production small intestine--nutrient absorption oral cavity--starch digestion large intestine--bile production
large intestine- bile production
Which of the following is NOT a major activity of the stomach? mechanical digestion HCL secretion mucus secretions nutrient absorption enzyme secretion
nutrient absorption
Fat digestion yields fatty acids and glycerol, whereas protein digestion yields amino acids; both digestive processes
require a low pH resulting from HCl production
occur inside cells in most animals
are catalyzed by the same enzyme
consume ATP
add a water molecule to break bonds
add a water molecule to break bonds
Choose the list that presents the four stages of food processing in the order in which they naturally occur.
digestion → ingestion → absorption → elimination
absorption → digestion → ingestion → elimination
ingestion → absorption → elimination → digestion
ingestion → digestion → elimination → absorption
ingestion → digestion → absorption → elimination
ingestion → digestion → absorption → elimination
The gastrovascular cavity differs from the alimentary canal in that only the gastrovascular cavity _____.
has only a single opening
Birth defects of the neural tube in humans _____.
Birth defects of the neural tube in humans _____.
can be prevented by ingestion of more vitamin A during the periconception interval
are reduced from about 6% without folic acid supplements in the periconception interval to about 1% when the supplements were taken
result from excess sodium in the pregnant woman’s diet
are not affected by nutritional considerations during pregnancy
are typically seen in 10-20% of male babies born in well-developed countries
are reduced from about 6% without folic acid supplements in the periconception interval to about 1% when the supplements were taken
To maintain adequate nutrition, animals require dietary access to certain amino acids. An amino acid that is referred to as “nonessential” would be best described as one that
can be made by the animal’s body from other substances
An advantage of a complete digestive system over a gastrovascular cavity is that the complete system
allows for specialized regions with specialized functions
Ingested dietary substances must cross cell membranes to be used by the body, a process known as
absorption
Secretin stimulates the \_\_\_\_ to secrete \_\_\_ pancreas ... bicarbonate pancreas ... pancreatic enzymes small intestine ... disaccharidases stomach ... bicarbonate liver ... liver enzymes
pancreas… bicarbonate
Cholecystokinin (CCK) stimulates the \_\_\_\_\_ to secrete \_\_\_\_\_.
pancreas ... bicarbonate
pancreas ... pancreatic enzymes
small intestine ... disaccharidases
stomach ... bicarbonate
liver ... liver enzymespancreas… pancreatic enzymes
The acidity of the stomach contents triggers the small intestine to secrete a hormone known as \_\_\_\_\_. cholecystokinin, or CCK histones TSH secretin pepsin
secretin
The presence of fatty acids and amino acids in the chyme from the stomach triggers the small intestine to secrete a hormone known as \_\_\_\_\_.
cholecystokinin, or CCK
histones
insulin
secretin
thyroxinecholecytokin, or CCK
Bile is produced by the \_\_\_\_\_ and stored by the \_\_\_\_\_ until it is secreted into the small intestine.
liver ... gall bladder
pancreas ... gall bladder
liver ... pancreas
gall bladder ... liver
esophagus ... stomachliver… gall bladder
Choose the correct anatomical sequence that presents the order in which food in the digestive system passes through.
esophagus → pharynx → stomach → small intestine
pharynx → small intestine → large intestine → stomach
pharynx → esophagus → stomach → small intestine → large intestine
pharynx → stomach → esophagus → small intestine
esophagus → stomach → pharynx → small intestine
pharynx → esophagus → stomach → small intestine → large intestine
The lower esophageal sphincter surrounds the upper opening into the stomach. If this sphincter failed to properly constrict, there might be a problem with _____.
too rapid emptying from the stomach into the small intestine
too rapid emptying of the small intestine into the large intestine
the control of defecation
the movement of swallowed food into the trachea rather than into the esophagus
regurgitation of acidic stomach contents into the esophagus, commonly called “heartburn”
regurgitation of acidic stomach contents into the esophagus, commonly called “heartburn”
In the digestive system, peristalsis is
voluntary control of the rectal sphincters regulating defecation.
the transport of nutrients to the liver through the hepatic portal vessel.
a process of fat emulsification in the small intestine.
smooth muscle contractions that move food along the esophagus.
a common cause of loss of appetite, fatigue, and dehydration.
smooth muscle contractions that move food along the esophagus.
Pepsin is a digestive enzyme that
helps stabilize fat-water emulsions.
splits maltose into monosaccharides.
is denatured and rendered inactive in solutions with low pH.
is manufactured by the pancreas.
begins the hydrolysis of proteins in the stomach.
begins the hydrolysis of proteins in the stomach.
The absorption of fats differs from that of carbohydrates in that the
fat absorption occurs in the stomach, whereas carbohydrates are absorbed from the small intestine. most absorbed fat first enters the lymphatic system, whereas carbohydrates directly enter the blood. processing of fats does not require any digestive enzymes, whereas the processing of carbohydrates does. fats, but not carbohydrates, are digested by bacteria before absorption. carbohydrates need to be emulsified before they can be digested, whereas fats do not.
most absorbed fat first enters the lymphatic system, whereas carbohydrates directly enter the blood
Glandular secretions that are released initially as inactive precursors of digestive enzymes are the
fat-solubilizing bile salts.
hormones such as gastrin.
acid-neutralizing bicarbonate.
carbohydrate-digesting enzymes.
protein-digesting enzymes.protein-digesting enzymes
Because adult lampreys attach onto the surface of large fish for long periods of time to feed on body fluids, they can accomplish nutritional balance without need for a
gallbladder.
intestine.
stomach.
pancreas.
liver.stomach
Earthworms, grasshoppers, and birds all have a
epiglottis pharynx gastric cecae larynx crop
crop
The molar teeth of herbivorous mammals are especially effective at
ripping.
piercing.
grinding.
splitting.
cutting.grinding
A group of animals among which a relatively long cecum is likely to be found is the
carnivores.
autotrophs.
omnivores.
heterotrophs.
herbivores.herbivores
Cattle are able to survive on a diet consisting almost entirely of plant material because
they are autotrophic.
they have cellulose-digesting, symbiotic microorganisms in chambers of their stomachs.
cattle, like rabbits, re-ingest their feces.
they manufacture all 15 amino acids out of sugars in the liver.
cattle saliva has enzymes capable of digesting cellulose.
they have cellulose-digesting, symbiotic microorganisms in chambers of their stomachs.
metabolic rate is ____
the total amount of energy an animal uses in a unit of time
Choose the list that correctly ranks metabolic rates per gram of body mass, from lowest to highest.
human, rabbit, snake
gazelle, lion, elephant
hummingbird, dog, mouse
fish, dog, mouse
human, cat, mouse, salamanderfish, dog, mouse
Constipation can result from the consumption of a substance that
promotes water reabsorption in the large intestine.
stimulates peristalsis.
contains plenty of fiber.
decreases water reabsorption in the small intestine.
speeds up movement of material in the large intestine.
promotes water reabsorption in the large intestine
What is the process of adding nonessential dilutes and wastes from the body fluids to the filtrate?
Secretion
Essential nutrients must be obtained from an animals diet. Which of the following is NOT one of the four classes of essential nutrients? Essential amino acids Essential sugars Essential fatty acids Vitamins Minerals
Essential sugars
What is the most common type of malnutrition among humans worldwide? Protein Fatty acid Carbohydrate Vitamin Mineral
Protein
A “complete digestive tract” differs from a gastrovascular cavity in that only the complete tract
Permits extracellular digestion
Has teeth and tentacles to help with ingestion
Uses its surface area for nutrient absorption
Has specialized compartments
Allows elimination of undigested wastes
Has specialized compartments
In humans the first opportunity for ingested food to undergo enzymatic hydrolysis is in the
Mouth Stomach Liver Small intestines Large intestine
Mouth
Stomach acid
Splits polypeptides into amino acids
Splits fats into fatty acids and glycerol
Activates pepsinogen into pepsin
Initiates the development of stomach ulcers
Inhibits the production of epithelial cells
Activates pepsinogen into pepsin
The bile salts function in fat digestion by
Dispersing big droplets of fats to small droplets
Cattle are able to survive on a diet of consisting almost entirely of plant material because…
They are chemoautotrophs
They manufacture all vitamins in the cecum
They have cellulose digesting, symbiotic micro organisms in chambers of their stomachs
Cattle re-ingest their feces
Cattle saliva has enzymes capable of digesting plant materials
They have cellulose digesting, symbiotic micro organisms in chambers of their stomachs
Obesity in humans is most clearly linked to
Type 1 diabetes and prostate cancer Type 1 diabetes and breast cancer Type 2 diabetes and muscle hypertrophy Type 2 diabetes and cardiovascular disease Type 2 diabetes and decreased appetite
Type 2 diabetes and cardiovascular disease
