ZOL1502 YEAR 2022
ASSIGNMENT 2 SEMESTER 2
NB; ALSO BOOK FOR YOUR EXAM WRITING
IN ADVANCE
Question 1 [10]
Explain what is meant by each of the following terms:
1.1 Embryonic diapause
Embryonic diapause, the temporary suspension of development of the embryo, is a fascinating
reproductive strategy that has been frequently exploited across the animal kingdom. It is
characterized by an arrest in development that occurs at the blastocyst stage in over 130 species of
mammals.
1.2 Kinetic skull
A kinetic skull was defined by VERSLUYS (1910, 1912) as one that. Allowed any intracranial
movements (besides those of the lower jaw). In simplest terms, cranial kinesis (or kinetism) occurs
whenever the. Upper jaw and palate, or the maxillary segment can be moved in rela-
, 1.3 Altricial
In biology, altricial species are those in which the young are underdeveloped at the time of birth, but
with the aid of their parents mature after birth. Precocial species are those in which the young are
relatively mature and mobile from the moment of birth or hatching.
1.4 Systematics
Systematics, or Taxonomy, is the study of the kinds of organisms of the past and living today, and of
the relationships among these organisms. Systematists collect and study the variety of plants and
animals and group them according to patterns of variation.
1.5 Countercurrent flow in fish gills
Fish transfer oxygen from the sea water to their blood using a highly efficient mechanism called
countercurrent exchange. Countercurrent exchange means the flow of water over the gills is in the
opposite direction to the flow of blood through the capillaries in the lamellae.
1.6 Monophyletic
A group composed of a collection of organisms, including the most recent common ancestor of all
those organisms and all the descendants of that most recent common ancestor. A monophyletic
taxon is also called a clade. Examples : Mammalia, Aves (birds), angiosperms, insects, etc.
1.7 Sun-azimuth orientation
The Sun's azimuth can be defined as the direction of a celestial object from the observer, expressed
as the angular distance from the north or south point of the horizon to the point at which a vertical
circle passing through the object intersects the horizon.
1.8 Paedomorphosis
Paedomorphosis is an alternative process to metamorphosis in which adults retain larval traits at the
adult stage. It is frequent in newts and salamanders, where larvae reach sexual maturity without
losing their gills. However, in some populations, larvae overwinter in water, while remaining
immature.
1.9 Phylogenetics
is the systematic study of reconstructing the past evolutionary history of extant species or taxa,
based on present-day data, such as morphologies or molecular information (sequence data). This
evolutionary history or phylogeny is ideally represented as a binary tree.
1.10 Hypotonic
In chemical biology, tonicity is a measure of the effective osmotic pressure gradient; the water
potential of two solutions separated by a partially-permeable cell membrane.
Question 2 [30]
ASSIGNMENT 2 SEMESTER 2
NB; ALSO BOOK FOR YOUR EXAM WRITING
IN ADVANCE
Question 1 [10]
Explain what is meant by each of the following terms:
1.1 Embryonic diapause
Embryonic diapause, the temporary suspension of development of the embryo, is a fascinating
reproductive strategy that has been frequently exploited across the animal kingdom. It is
characterized by an arrest in development that occurs at the blastocyst stage in over 130 species of
mammals.
1.2 Kinetic skull
A kinetic skull was defined by VERSLUYS (1910, 1912) as one that. Allowed any intracranial
movements (besides those of the lower jaw). In simplest terms, cranial kinesis (or kinetism) occurs
whenever the. Upper jaw and palate, or the maxillary segment can be moved in rela-
, 1.3 Altricial
In biology, altricial species are those in which the young are underdeveloped at the time of birth, but
with the aid of their parents mature after birth. Precocial species are those in which the young are
relatively mature and mobile from the moment of birth or hatching.
1.4 Systematics
Systematics, or Taxonomy, is the study of the kinds of organisms of the past and living today, and of
the relationships among these organisms. Systematists collect and study the variety of plants and
animals and group them according to patterns of variation.
1.5 Countercurrent flow in fish gills
Fish transfer oxygen from the sea water to their blood using a highly efficient mechanism called
countercurrent exchange. Countercurrent exchange means the flow of water over the gills is in the
opposite direction to the flow of blood through the capillaries in the lamellae.
1.6 Monophyletic
A group composed of a collection of organisms, including the most recent common ancestor of all
those organisms and all the descendants of that most recent common ancestor. A monophyletic
taxon is also called a clade. Examples : Mammalia, Aves (birds), angiosperms, insects, etc.
1.7 Sun-azimuth orientation
The Sun's azimuth can be defined as the direction of a celestial object from the observer, expressed
as the angular distance from the north or south point of the horizon to the point at which a vertical
circle passing through the object intersects the horizon.
1.8 Paedomorphosis
Paedomorphosis is an alternative process to metamorphosis in which adults retain larval traits at the
adult stage. It is frequent in newts and salamanders, where larvae reach sexual maturity without
losing their gills. However, in some populations, larvae overwinter in water, while remaining
immature.
1.9 Phylogenetics
is the systematic study of reconstructing the past evolutionary history of extant species or taxa,
based on present-day data, such as morphologies or molecular information (sequence data). This
evolutionary history or phylogeny is ideally represented as a binary tree.
1.10 Hypotonic
In chemical biology, tonicity is a measure of the effective osmotic pressure gradient; the water
potential of two solutions separated by a partially-permeable cell membrane.
Question 2 [30]
