BIO 121 Final Study Guide (Ch. 10-11.20) Fall 2025
Questions With complete Solutions
___ aid in flight and
provide insulation and
waterproofing. (1 fact) Correct Answers feathers
• Birds have strong, light,
honeycombed bones and
powerful breast muscles.
___ are mammals that mature in pouches. Correct Answers
marsupials
• After a brief pregnancy, a ___ gives
birth to a tiny embryonic offspring that
completes its development in its mother's
pouch, attached to a nipple.
-Most marsupials are found in
Australia
• they split off from the other continents
around 60 mya.
• Isolated from the evolution of later groups
of mammals, marsupials diversified
extensively.
___ are tetrapods that have hair
and produce milk in mammary glands. Correct Answers
mammals
• After the dinosaur mass
extinction 65 mya, they rapidly
diversified.
• Modern mammals can
,be divided into three
groups:
- Monotremes
- Marsupials
- Eutherians
___ are the only surviving
egg-laying mammals. Correct Answers monotremes
• examples: duck-billed platypus and four species of
echidna.
___ fishes were the first group to have
internal skeletons reinforced with calcium. (then list 2 facts)
Correct Answers Bony fish
• They also have a swim bladder to maintain
buoyancy
-have an operculum (area covering gills that
circulates water over the gills)
___ were the first tetrapods. (3 fact) Correct Answers
amphibians
• They were followed
by the evolution of
reptiles (including
birds).
-live on land, but must
reproduce in water.
• exhibit a
blend of aquatic and
terrestrial adaptations.
(same word)
, ________ offspring are born fully
developed after maturing with a placenta(2 facts) Correct
Answers eutherian
• it connects
the developing fetus
to the uterine wall.
• This allows nutrient
uptake, waste
elimination, and gas
exchange via the
mother's blood
supply.
absorption process: Correct Answers Within the colon, the
main portion of the large intestine, water is absorbed
Accessory organs function: Correct Answers secrete specific
digestive chemicals into the alimentary canal via ducts
alimentary canal Correct Answers digestive tube that extends
from the mouth to the anus
All animals, besides the cnidarians, exhibit ___ ___: (explain
what the term is) Correct Answers Bilateral symmetry. they
can
be split into roughly mirrored halves
by slicing down the mid-line.
All chordates are recognized by four features: Correct Answers
-pharynqeal slits
Questions With complete Solutions
___ aid in flight and
provide insulation and
waterproofing. (1 fact) Correct Answers feathers
• Birds have strong, light,
honeycombed bones and
powerful breast muscles.
___ are mammals that mature in pouches. Correct Answers
marsupials
• After a brief pregnancy, a ___ gives
birth to a tiny embryonic offspring that
completes its development in its mother's
pouch, attached to a nipple.
-Most marsupials are found in
Australia
• they split off from the other continents
around 60 mya.
• Isolated from the evolution of later groups
of mammals, marsupials diversified
extensively.
___ are tetrapods that have hair
and produce milk in mammary glands. Correct Answers
mammals
• After the dinosaur mass
extinction 65 mya, they rapidly
diversified.
• Modern mammals can
,be divided into three
groups:
- Monotremes
- Marsupials
- Eutherians
___ are the only surviving
egg-laying mammals. Correct Answers monotremes
• examples: duck-billed platypus and four species of
echidna.
___ fishes were the first group to have
internal skeletons reinforced with calcium. (then list 2 facts)
Correct Answers Bony fish
• They also have a swim bladder to maintain
buoyancy
-have an operculum (area covering gills that
circulates water over the gills)
___ were the first tetrapods. (3 fact) Correct Answers
amphibians
• They were followed
by the evolution of
reptiles (including
birds).
-live on land, but must
reproduce in water.
• exhibit a
blend of aquatic and
terrestrial adaptations.
(same word)
, ________ offspring are born fully
developed after maturing with a placenta(2 facts) Correct
Answers eutherian
• it connects
the developing fetus
to the uterine wall.
• This allows nutrient
uptake, waste
elimination, and gas
exchange via the
mother's blood
supply.
absorption process: Correct Answers Within the colon, the
main portion of the large intestine, water is absorbed
Accessory organs function: Correct Answers secrete specific
digestive chemicals into the alimentary canal via ducts
alimentary canal Correct Answers digestive tube that extends
from the mouth to the anus
All animals, besides the cnidarians, exhibit ___ ___: (explain
what the term is) Correct Answers Bilateral symmetry. they
can
be split into roughly mirrored halves
by slicing down the mid-line.
All chordates are recognized by four features: Correct Answers
-pharynqeal slits
