BIOL 2402 - Exam 1 – UMSL Questions | 2026/2027 |
Answers Correct | With Complete Solutions
*antlers vs horns Correct Answers Antlers - found in cervids
(deer, moose, etc) only in males, made of bone, shed yearly
Horns - found in bovids (goats, sheep, bison), both sexes have
horns, bony base surrounded by keratin sheath, not shed
UHH HOW IS THE VELVET DIFFERENT FROM THE
SKIN/INTEGUMENT????
*Cephalochordata circulation Correct Answers •Colorless
plasma (no cells, no oxygen-transport pigment)
•No heart, sinus venosus is positioned where a heart would be
•Simple diffusion contributes to most respiration
*Determinate vs indeterminate? Correct Answers The
Deuterostomes also show indeterminate development, in which
each of the cells of the eight-cell embryo if separated remain
capable of developing as complete organisms. This contrasts to
determinate development, in which the development fate of each
cell in the adult organism has already been determined.
Deuterostome - Indeterminate
Protostome - Determinate
Identical Twins
Embryonic Stem Cells
,*Endostyle vs Thyroid Correct Answers •Endostyle - groove in
the floor of the pharynx excretes mucus to catch particles for
filter-feeding
•Thyroid - gland that produces hormones involved in
growth/metabolism
•Homologous structures: both are involved in iodine metabolism
and are derived from the same tissue
*Innovations: Vertebral column Correct Answers •Replaces the
notochord as means of body support
•Intervertebral bodies (cartilaginous or fibrous) Our discs are
unique to mammals
•Lateral Correct Answers l - the sides, away from the midline
•Medial Correct Answers - the midline, or toward the midline
•New epidermal cells are produced in stratum basale Correct
Answers
•Pectoral region Correct Answers - chest, supports the
forelimbs
•Pelvic region Correct Answers - pelvis, supports the hindlimbs
Acanthodians are known for what four characteristics Correct
Answers •Prominent spines along the body
•Ossified vertebral column
•Reduced armor
, •Some possess gill slits open to the exterior, others had bony
opercula
Agnathans - Vertebrate Classification Terms Correct Answers
•jawless fishes
Amniotes - Vertebrate Classification Terms Correct Answers
•produce embryos wrapped in amnion (protective casing around
developing embryo)
Amniotes are Correct Answers reptiles, birds, & mammals
Analogous structures Correct Answers Have similar functions
as a result of convergent evolution [the phenomenon of similar
structures evolving independently - e.g. vertebrate flight]
Different Structure/Similar Function
Note: Sometimes characters are only considered analogous if
they are not a result of shared ancestry
Analogy Correct Answers Features that are shared as a result of
a common function
Anamniotes - Vertebrate Classification Terms Correct Answers
•no amnion (e.g. fishes and amphibians)
antlers vs horns Correct Answers Horn - Underlying bone
pushes the integument up, the integument is then cornfield (like
hardened), providing a horn. Found in animals like deer and
moose (cervids)
, Antlers - These are actual exposed bone (or bone covered with
velvet) that has protruded out of the head, and has broken past
the integument. Usually covered with valet that eventually falls
of, revealing bare bone.
Begin CH3 Correct Answers
Bilateral Correct Answers Only the midsagittal plane divides
the body into equal parts
Bony fishes Integument (Scale Types) Correct Answers
•Dermal scale types:
1.Ganoid - thick enamel, no dentin
2.Cycloid (teleosts) - no enamel, dentin, or vascular bone layer,
just dermis
3.Ctenoid (teleosts) - like cycloid but with fringe on posterior
side
VIEW PICTURE ON SLIDE 14 AND 15, CH 6
Carcinisation Correct Answers Evolving to become crab
CH6 Integuments Correct Answers
Changing color? Correct Answers •Shuttling pigment granules
around different parts of the chromatophore
•Mediated by the endocrine system
•In some, increased UV exposure causes an increase in pigment
production to protect cells from continued exposure
•
Answers Correct | With Complete Solutions
*antlers vs horns Correct Answers Antlers - found in cervids
(deer, moose, etc) only in males, made of bone, shed yearly
Horns - found in bovids (goats, sheep, bison), both sexes have
horns, bony base surrounded by keratin sheath, not shed
UHH HOW IS THE VELVET DIFFERENT FROM THE
SKIN/INTEGUMENT????
*Cephalochordata circulation Correct Answers •Colorless
plasma (no cells, no oxygen-transport pigment)
•No heart, sinus venosus is positioned where a heart would be
•Simple diffusion contributes to most respiration
*Determinate vs indeterminate? Correct Answers The
Deuterostomes also show indeterminate development, in which
each of the cells of the eight-cell embryo if separated remain
capable of developing as complete organisms. This contrasts to
determinate development, in which the development fate of each
cell in the adult organism has already been determined.
Deuterostome - Indeterminate
Protostome - Determinate
Identical Twins
Embryonic Stem Cells
,*Endostyle vs Thyroid Correct Answers •Endostyle - groove in
the floor of the pharynx excretes mucus to catch particles for
filter-feeding
•Thyroid - gland that produces hormones involved in
growth/metabolism
•Homologous structures: both are involved in iodine metabolism
and are derived from the same tissue
*Innovations: Vertebral column Correct Answers •Replaces the
notochord as means of body support
•Intervertebral bodies (cartilaginous or fibrous) Our discs are
unique to mammals
•Lateral Correct Answers l - the sides, away from the midline
•Medial Correct Answers - the midline, or toward the midline
•New epidermal cells are produced in stratum basale Correct
Answers
•Pectoral region Correct Answers - chest, supports the
forelimbs
•Pelvic region Correct Answers - pelvis, supports the hindlimbs
Acanthodians are known for what four characteristics Correct
Answers •Prominent spines along the body
•Ossified vertebral column
•Reduced armor
, •Some possess gill slits open to the exterior, others had bony
opercula
Agnathans - Vertebrate Classification Terms Correct Answers
•jawless fishes
Amniotes - Vertebrate Classification Terms Correct Answers
•produce embryos wrapped in amnion (protective casing around
developing embryo)
Amniotes are Correct Answers reptiles, birds, & mammals
Analogous structures Correct Answers Have similar functions
as a result of convergent evolution [the phenomenon of similar
structures evolving independently - e.g. vertebrate flight]
Different Structure/Similar Function
Note: Sometimes characters are only considered analogous if
they are not a result of shared ancestry
Analogy Correct Answers Features that are shared as a result of
a common function
Anamniotes - Vertebrate Classification Terms Correct Answers
•no amnion (e.g. fishes and amphibians)
antlers vs horns Correct Answers Horn - Underlying bone
pushes the integument up, the integument is then cornfield (like
hardened), providing a horn. Found in animals like deer and
moose (cervids)
, Antlers - These are actual exposed bone (or bone covered with
velvet) that has protruded out of the head, and has broken past
the integument. Usually covered with valet that eventually falls
of, revealing bare bone.
Begin CH3 Correct Answers
Bilateral Correct Answers Only the midsagittal plane divides
the body into equal parts
Bony fishes Integument (Scale Types) Correct Answers
•Dermal scale types:
1.Ganoid - thick enamel, no dentin
2.Cycloid (teleosts) - no enamel, dentin, or vascular bone layer,
just dermis
3.Ctenoid (teleosts) - like cycloid but with fringe on posterior
side
VIEW PICTURE ON SLIDE 14 AND 15, CH 6
Carcinisation Correct Answers Evolving to become crab
CH6 Integuments Correct Answers
Changing color? Correct Answers •Shuttling pigment granules
around different parts of the chromatophore
•Mediated by the endocrine system
•In some, increased UV exposure causes an increase in pigment
production to protect cells from continued exposure
•