- Describe the changes in the egg-cell which precede fertilization;
describe the process of fertilization and the formation of the primary
cell-layers, as exhibited, in three of the animal types known to you.
What is the notochord, and how is it developed in the frog?
- Describe the early stages in the development of the egg of the fowl
as far as the closure of the neural groove. How do you account for
the primitive streak?
- Describe the cleavage and the surface appearances of the egg of
the frog and of the rabbit, up to the time when the first gill-slits
appear in the embryo. Give illustrative diagrams of what you
describe.
- Describe the structure and cleavage of the ovum (a) of the frog, (b)
of the fowl, and (c) of the rabbit. (d) Explain as far as possible the
differences in the cleavage of these three eggs. (e) Point out how the
embryo is nourished in each case, and (f) describe the constitution of
the placenta in the rabbit.
- (a) What are the protovertebrae? (b) How does the notochord
originate in the frog? (c) How are the vertebrae laid down in the
tadpole? (d) Describe the vertebral column of the adult frog. (e) In what
important respects do the centra of the vertebrae of the frog, the
dog-fish, and the rabbit differ from one another?
- Give an account of the more important features in the development
of the frog.
- What temporary organs are developed in the embryo frog which are
absent from the embryo bird and mammal, and what in the two latter
which are absent from the former?
- Draw diagrams, with the parts named, of the heart and great
arteries of the frog, giving descriptions only in so far as is necessary
to explain your diagrams; trace the development of these structures in
the tadpole; point out particularly in which of the embryonic visceral
(branchial) arches the great arteries of the adult run.
- Trace the history of the post-oral gill-slits and their accompanying
cartilaginous bars and vascular arches in the frog, fowl, and rabbit.
- Give a short account, with illustrative figures, of the mode of
formation of the primary germinal layers in amphioxus and in the frog.
What explanation can you give of the differences between the two
cases?
- Give a short account, with diagrammatic figures, of the principal
changes which occur in the circulatory and respiratory organs during
the metamorphosis of the tadpole into the frog.
- How do protozoa differ from higher animals (metazoa) as regards (a) structure, (b) reproduction? Compare the process of fission in an amoeba with the segmentation of the ovum in amphioxus, pointing out the resemblances and differences between the two cases.
-Miscellaneous Questions._
[Most of these questions were actually set at the Biological Examinations of London University.]
{In Both Editions.}
- Describe (a) the digestive, (b) the circulatory, (c) the excretory, and
(d) the reproductive organs of the amphioxus.
- Describe the stomach and intestines of the dog-fish and rabbit, and
point out in what way their differences are connected with diet.
- Describe the mechanism of respiration in the adult frog, and
contrast it with that of the tadpole.
- Give an account of the structure of the epidermis and its
outgrowths in the frog and the rabbit.
- Describe the organs of circulation (heart and main arteries and
veins) and respiration in the frog in its mature and immature states.
- Give a brief account of the physiology of respiration. Describe fully
the means by which respiration is effected in the following animals:--
frog, amphioxus, rabbit, and dog-fish.
- Describe the minute structure of the blood of the rabbit, frog, and
amphioxus.
- Describe and illustrate by means of sketches the chief points of
difference between the skeleton of the rabbit as a typical mammal,
and that of the common frog as a typical amphibian.
- (a) Explain what is meant by the term "central nervous system."
(b) Describe the tissue elements which enter into its composition.
(c) Explain, as far as you can, the function of each structure
described. (d) How is the central nervous system developed in the
frog, and (e) in the rabbit? (f) What conclusions may be drawn from
the facts stated as to the origin of the central nervous system in
evolution?
- Give an account of the structure (including histology) and of the
functions of the spinal cord and spinal nerves of the frog.
- Give a description of the minute structure and chemical
characters of the following tissues as seen in the frog:-- cartilage,
bone, muscle. From which of the primary cell-layers of the embryo are
they respectively developed?
- What substance is excreted by the renal organ of a frog, and what
relation does this substance bear to the general life of the organism?
Describe the parts by which similar excretion is believed to be
effected in amoeba, hydra, earthworm, mussel, and lobster.
- Describe, with illustrative sketches, the structure of the connective
tissue, cartilage, and muscular tissue of a frog. Also describe the
structure of the muscular tissue of the lobster and snail.
- Give in account of the more important features in the
development of the frog.
- Describe and compare the structure of the renal organs in a frog
and a rabbit.
- Give an account of the structure of the genito-urinary organs of the
frog. Compare these organs of the frog with those of the dog-fish and
of the rabbit. Distinguish in each case the conditions of the two
sexes, and describe briefly the microscopic structure and
development of the ova and of the spermatozoa.
- Describe, with diagrams, the arrangement of the urinary and
generative organs in the male of (a) the rabbit, (b) the dog-fish, and
(c) the frog; (d) point out the most important differences between
them.
- (a) Describe the structure of the ovarian egg of the rabbit, (b) and
of the pigeon, (c) and of the frog; (d) from what part of the embryo do
they originate? (e) What is the structure and origin of the ovarian
follicle in the rabbit, and (f) of the ovarian stroma? (g) What is the
"granulosa" and what the "zona pellucida"?
- Describe the pre-segmentation changes, mode of impregnation,
and early stages of development in the ovum of the frog, as far as the
closure of the neural canal.
- Illustrate, with diagrams, from the structure of typical organisms, the principle of repetition of similar parts.
-Note on Making Comparisons._
Students preparing for examinations are frequently troubled by "comparison" questions. Tabulation is often recommended, but we are inclined to favour a rather more flexible plan of marking off differences and resemblances. In tabulation a considerable loss of time is occasioned by writing down the features of both the things compared, and this is a serious consideration for the examinee. We advise him therefore, first, if he possibly can, to draw side by side and in corresponding positions the two things under consideration, and then, going over them in a methodical way, to state simply the difference between each homologous part. We append as examples three test answers actually submitted (with figures) in "Correspondence" work:--