Download Tutorial Kit (Applied Biology-200 L)

COVENANT
UNIVERSITY
OMEGA SEMESTER TUTORIAL KIT
(VOL. 2)
PROGRAMME:APPLIED BIOL.
200 LEVEL
DISCLAIMER
The contents of this document are intended for practice and learning purposes at the undergraduate
level. The materials are from different sources including the internet and the contributors do not
in any way claim authorship or ownership of them. The materials are also not to be used for any
commercial purpose.
1
LIST OF COURSES
BLY221: Basic Invertebrate Zoology
BLY222: Plant Physiology
BLY223: Basic Chordate Zoology
*Not included
2
COVENANT UNIVERSITY
CANAANLAND, KM 10 IDIROKO ROAD
P.M.B 1023 OTA, OGUN STATE, NIGERIA
TITLE OF EXAMINATION: B.Sc DEGREE EXAMINATIONS
COLLEGE: SCIENCE AND TECHNOLOGY
DEPARTMENT: BIOLOGICAL SCIENCES
SESSION: 2015/2016
SEMESTER: OMEGA
PROGRAMME: APPLIED BIOLOGY AND BIOTECHNOLOGY
COURSE CODE: BLY 221
COURSE UNIT: 2
COURSE TITLE: BASIC INVERTEBRATE ZOOLOGY
TIME ALLOWED: 2hrs
INSTRUCTION(S): ATTEMPT THREE QUESTIONS IN ALL; AT LEASE ONE FROM
EACH SECTION
1
SECTION A
a) What are the functions of the afferent and efferent pulmonary veins in Archachatina? ……..
2 marks
b) Why is it important that the giant land snails secrete uric acid as their waste products? ….. 1
mark
c) What is the function of symbiotic bacteria in the gut of Archachatina? ………….. 1 mark
d) Mention any one habit of Archachatina …………. 1 marks
e) Differentiate between the auricle and ventricle of Archachatina …….. 2 marks
f) How many body divisions can shrimps have? Name them. …….. 3 marks
g) What are the components of the nervous system in Earthworms? ………. 3 marks
h) Describe the process of reproduction in Earthworms ………………… 10 marks
2a
b
Write briefly on reproduction in leeches. ................. 10 marks
(i) Mention the receptor cells that can be found on the body of sea stars ……. 3 marks
(ii) What structure in the water vascular system of star fish leads to the outside? ... 1 mark
(iii) The first pair of antenna in crustaceans is called? ……2 mark
3
(iv) How many segments altogether occur on the body of shrimps? ……….. 1 marks
(v) Asexual reproduction in the Oligochaetes is by? ………… 1 mark
(vi) What is the function of green glands in shrimps? ………… 1 mark
(vii) What is the primary function of the tube feet of sea stars? …….. 2 marks
(viii) What are the functions of flexors and extensors in crustaceans? ……. 2 marks
3a
b
c
Highlight four ways by which Hirudo is well equipped for its feeding habit… 6 marks
Define the following terms:
i.
Annuli ………… 2 marks
ii.
Chaetae ………… 2 marks
iii.
Diapause ………… 2 marks
iv.
Coelom ………… 2 marks
v.
Metamerism ………… 2 marks
vi.
Ureotelic ………………..2 marks
Mention any five features of the subclass Crustacea …………. 5 marks
SECTION B
1. (a) With labeled diagrams, describe locomotion in the following invertebrates:
(i)Amoeba (ii) Paramecium and (iii) Hydra
15 marks
(b)Planarians possess high power of regeneration. Support this statement by describing how
asexual reproduction takes place in Dugesia tigrina.
8.5 marks
2. (a)Give a concise description of the life cycle of Moon Jelly fish, Aurelia aurita 10 marks
(b)Briefly describe sexual reproduction in Paramecium
13.5 marks
4
COVENANTUNIVERSITY
CANAANLAND, KM 10, IDIROKO ROAD
P.M.B 1023, OTA, OGUN STATE, NIGERIA.
TITLE OF EXAMINATION: B.Sc EXAMINATION
COLLEGE: COLLEGE OF SCIENCE AND TECHNOLOGY
DEPARTMENT: BIOLOGICAL SCIENCES
SESSION: 2015/2016
SEMESTER: OMEGA
COURSE CODE: BLY 221
CREDIT UNIT: 2 UNITS
COURSE TITLE: BASIC INVERTEBRATE ZOOLOGY
INSTRUCTION: ANSWER ANY THREE QUESTIONS
TIME: 2 HOURS
1
a) Afferent pulmonary vein takes blood to the lungs while the efferent pulmonary vein takes
blood away from it ........................................................................……..2 marks
b) In order to conserve water ..........................................................................…..1 mark
c) To digest cellulose ............................................................................…………1 mark
d) They are nocturnal, inactive in dry season ......................................………….1 marks
e) Auricle is thin-walled and triangular, ventricle is muscular and ovoid …….. 2 marks
f) Two. Cephalothorax and abdomen .......................................................……...3 marks
g) Supra-oesophageal ganglion and sub-oesophageal ganglion ...............………3 marks
h)
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
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
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
Lumbricus breeds continually, but some have one yearly reproductive season
Copulation with mutual sperm transfer
Ventral contact between oppositely oriented worms
Sperm swim in a ventral sperm groove from male gonopores to openings of partner’s seminal
receptacles
Indirect sperm transfer, Some worms have copulatory organ for direct sperm transfer
Cocoons secreted a few days after copulation
Eggs and partner’s sperm (from seminal receptacles) deposited into cocoon
External and Cross fertilization
Cocoon slides of head, and ends pinch off; mucus tube disintegrates
Terrestrial species deposit cocoons in soil, aquatic species deposit cocoons in debris or mud,
or attach to vegetation
10 marks
5
2a
They have no powers of regeneration and so do not reproduce asexually; though hermaphrodites,
they cross-fertilize; the male organs consist of 4-10 pairs of segmentally arranged spherical testes each
contained in a capsule; the testes discharges via two lateral vas deferens, each of which enlarges to
form a seminal vesicle; there is one pair of ovaries situated in front of the anterior pair of testes, each
ovary is enclosed in an ovisac; a short oviduct emerges from each ovary and joins to form a common
duct and a short vagina leading to the female gonopore; during copulation, two leeches lie head to
tail; the penis is inserted into the vagina of the partner and exchange of sperms takes place; after
copulation, their clitellum secretes a cocoon that receives eggs and sperms; they bury the cocoon in
muds, attach them to submerged objects or place them on damp soil and development is direct.
............................................................................................ 10 marks
2b
i)
ii)
iii)
iv)
v)
vi)
vii)
viii)
Photoreceptors, chemoreceptors and tactile cells ..............................................3 marks
Madrepodite ..................................................................................................... 1 mark
Antennules
…..........................................…2 marks
20
......................................................……………… 1 marks
Transverse fission ……...................................................................................... 2 marks
Excretion
......................................................……………… 1 mark
Locomotion ….............................................................................................….. 1 mark
Flexors draw a limb toward the body and extensors straighten a limb out …… 2 marks
3a
Absence of setae, large blood consumption in a single feeding, presence of suckers, many
caeca, large crop
........................................................... 6 marks
3b
Annuli – Circular rings …............................................................……… 2 marks
Chaetae – Chitonous bristle or seta for movement …..................……… 2 marks
Diapause – Period which the metabolic activity of organisms ceases ….. 2 marks
Coelom – Fluid-filled body cavity in multicellular organisms ………… 2 marks
Metamerism – Division of an animal’s body into repeated similar rings or segments each of
which is built on the same plan …...................................……… 2 marks
Ureotelic – Organisms that pas out urea as their excretory product
3c
Secreted cuticle is made of chitin, protein, and calcareous material
Heavy plates have more calcareous deposits - joints are soft and thin, allowing flexibility
Dorsal tergum and ventral sternum are plates on each somite lacking a carapace
Anterior end is a nonsegmented rostrum and the posterior end is the unsegmented telson
Crustaceans are the only arthropods that have two pairs of antennae
They also have a pair of mandibles (jaw-like appendages) and two pairs of maxillae on the
head
Each body segment usually has one pair of appendages
6
Muscular and nervous systems and segmentation exhibit metamerism of annelid-like
ancestors.
Open circulatory system
Sensory system of eyes, statocysts, tactile organs and chemoreceptors
Compound eyes are made of many units called ommatidia
Growth occurs after ecdysis
Development is indirect
Any 5 = 5 marks
SECTION B
3. (a) With labeled diagrams, describe locomotion in the following invertebrates:
(i)Amoeba (ii) Paramecium and (iii) Hydra
(15 marks)
(b)Planarians possess high power of regeneration. Support this statement by describing how
asexual reproduction takes place in Dugesia tigrina.
(8.5 marks)
4. (a)Give a concise description of the life cycle of Moon Jelly fish (Aurelia aurita)
(10 marks)
(b)Briefly describe sexual reproduction in Paramecium
(13.5 marks)
Marking Guide
1a) Locomotion
(i) Amoeba





At one point on the amoeba, the ectoplasm extends and the endoplasm flows in, forming
a pseudopodium.
The pseudopodium continues to extend and the endoplasm continues to flow so that the
whole amoeba is moving to the right.
A new pseudopodium starts to form and …
…the endoplasm flows into this.
As a result, the amoeba has changed its direction of movement
Any 4 points including diagram=5 marks
7
(ii)Paramecium




Paramecium moves with the aid of cilia which beats in a rhythmic pattern.
Individual cilia bend and straighten rapidly in such a way that the recovery stroke offers
minimal resistance and the bending stroke helps propel paramecium through the water.
If paramecium encounters an obstacle, it reverses the ciliary beat and moves back. It then
changes direction slightly and moves forward. It will do this repeatedly until it gets past the
obstruction.
This reaction also shows that paramecium is sensitive to stimuli

Ciliates move by cilia which are permanent protrusion of the cytoplasm that are fixed in
position and are arranged in parallel rows. Waves of cilliary beat pass from the anterior to
the posterior part of the body (a ciliary beat consists of a fast effective strooke, followed by a
slower recovery stroke).

The cilia in each row beat in unison but slightly later than the row in front in a metachronal
rythym.

The body rotates on its longitudinal axis as the animal moves forward because each cilium
strikes the body obliquely. Also the path of movement is spiral.
1.Paramecium
hits an
obstacle
reverses its
ciliary
beat
Moves
forward again
Turns slightly
Any 4 points including diagram=5 marks
8
(iii)Hydra
Locomotion occurs by







Somersaulting
Amoeboid Movement of Basal Disc
Detachment and floating with currents
Ectodermal contraction and ectodermal relaxation produce an elongated and narrow form.
Hydra searches for food in its immediate vicinity by circling its tentaclular region around,
with the basal disc as center.
It moves from place to place by somersaulting or in the manner of a looper caterpillar.
It can also glide on its disc or move freely by movement of its tentacles.
Any 4 points including diagram=5 marks
(1b)Asexua[ Reproduction in Dugesia









Asexual reproduction takes place by transverse binary fission.
Amazing regenerators (1/300th of body can grow into an entire worm)
Transverse fission – posterior end attaches, anterior end pulls and separates
Paratomy
Fragmentation – cyst forms around fragment. Regeneration occurs and cyst hatches
Parthenogenesis – “virgin birth”
Fission occurs when the animal has attained maximum size.
The posterior end adheres firmly while the anterior end moves forward so that a constriction
appears behind the pharynx.
The constriction gradually deepens, finally dividing the animal into two halves each of which
regenerates its missing parts.
Any 3 points mentioned (2 marks each) = 6 marks
9
2.5 marks
Total= (5+5+5+6+2.5) =23.5 marks
2a. life cycle of Aurelia








Life cycle of Aurelia
Mature Aurelia medusae release gametes from the gonads into the gastrovascular cavity.
The gametes exit from the mouth and fertilization is external.
The fertilized eggs or zygotes develop into ciliated planula larvae.
The larvae develop into a small, trumpet-shaped polyp, called a scyphistoma.
Under appropriate environmental conditions, the scyphistoma transforms into a strobila.
The strobila develops and releases by transverse fission a series of saucer-shaped ephyra
larvae,
The ephyra larva breaks away one by one and become the medusae.
The ephyra larvae gradually transform into adult jellyfish to complete the life cycle.
8 marks
2 marks
(b) Sexual Reproduction in Paramecium


Sexual reproduction is by conjugation.
It involves the exchange of nuclear materials and not the fusion of gametes.
10






During conjugation, the macronucleus disintegrates and the micronuclei which are diploid,
divide by meiosis so that four haploid pronuclei are formed from each micronucleus.
Typically, three out of these disintegrate while the remaining pronucleus divides into a
stationary and a migratory nucleus.
The migratory pronucleus migrates through the cytoplasmic tube into the other and fuses
with the stationary pronucleus.
Exchange of pronucleus is reciprocal, resulting in the formation of a synkaryon (nucleus
formed by the fusion of pronucleus from one individual and the pronucleus of its partner).
The conjugants now separate
The zygotic nucleus in each of them divides repeatedly to form four mega and four micronuclei. Cytoplasmic division of each exconjugant results in the formation of four paramecia.
Any 8 key steps highlighted=8marks
5.5 marks
Total(8+2+8+5.5)=23.5 marks
11
COVENANTUNIVERSITY
CANAANLAND, KM 10, IDIROKO ROAD
P.M.B 1023, OTA, OGUN STATE, NIGERIA.
TITLE OF EXAMINATION: B.Sc EXAMINATION
COLLEGE: SCIENCE AND TECHNOLOGY
DEPARTMENT: BIOLOGICAL SCIENCES
SESSION: 2015/2016
SEMESTER: OMEGA
COURSE CODE: BLY 222
CREDIT UNIT: 2
COURSE TITLE: PLANT PHYSIOLOGY
INSTRUCTION: ANSWER ANY THREE QUESTIONS TIME: 2 HOURS
1a. Highlight 8 physico-chemical properties of water and the roles they play in plant. (8 marks)
b. Describe the mechanisms of ascent of sap in the plant.
(8 marks)
c. Explain the mechanism of carbon rescue from photorespiration.
(7½ marks)
2.
i.
ii.
iii.
iv.
v.
vi.
vii.
viii.
Compare and contrast the following:
Hypertonic and Hypotonic Cells
Cohesion and Tension Concepts
Apoplast and Symplast
Diffusion and bulkflow
Passive and active transport
Photorespiration and Photosynthesis
C3 and C4 plants
C4 Carbon Cycle and Crassulacean Acid Metabolism
(24 marks)
3a. Compare glycolysis in plant and animals
5 marks
b. List 10 enzymes involved in glycolysis
c. Discuss the fate of pyruvate
10 marks
8 marks
4a. With the aid of a diagram only, describe the Tricarboxylic acid cycle
12 marks
b. Briefly describe the phases of growth in plant
6 marks
c. Discus the components of classical growth analysis in plants, emphasizing the needed
measurements and units.
5 marks
5a. State different causes of physiological innate dormancy with solutions
8 marks
b. Write an essay on the different parts of a germinating seed with respect to the physiological
processes they perform
12 marks
12
COVENANTUNIVERSITY
CANAANLAND, KM 10, IDIROKO ROAD
P.M.B 1023, OTA, OGUN STATE, NIGERIA.
TITLE OF EXAMINATION: B.Sc EXAMINATION
COLLEGE: SCIENCE AND TECHNOLOGY
DEPARTMENT: BIOLOGICAL SCIENCES
SESSION: 2015/2016 SEMESTER: OMEGA
COURSE CODE: BLY 222 CREDIT UNIT: 2
COURSE TITLE: PLANT PHYSIOLOGY
INSTRUCTION: ANSWER ANY THREE QUESTIONS TIME: 2 HOURS
MARKING SCHEME
1a. Highlight 8 physico-chemical properties of water and the roles they play in plant. (8 marks)
 Polarity and high dielectric constant make it serves as universal solvent for salts and
many non-ionizable organic but polar molecules
 Acts as electron and proton donor in photosynthesis for the production of light
reaction’s products, NADPH and ATP
 Hydrogen bonds allow for cohesion which helps in water transport in column
 Adhesion allows molecules to cling to surface of walls of conducting vessels
 High specific heat capacity (a thermal property) helps to maintain the temperature
 High latent heat of vaporisation (a thermal property) maintain the moisture content and
cooling of the plant
 High boiling point, which aids in the steady state of water as liquid and it does not
vaporize in undue time.
 Exists in 3 states (solid, liquid and vapour); enters the plant as liquid and goes out as
vapour
 High surface tension facilitate water to move in the soil, to rise in capillary, and
to pull water through the xylem
 Maximum density at 4°C ensures that water in plant rarely freezes
 High viscosity is very important in ascent of sap
 High tensile strength is very important in ascent of sap
 High transmission of light which allows for photosynthesis under submerged
situations
 Water is a reagent that is involved in most biochemical reactions in the plant
13

It serves as a medium for transporting dissolved substances like gases minerals and
Solutes


Incompressibility of water allows for cell turgidity, which gives rigidity to the plant
Molecular size is small enough to pass through a semi-permeable membrane facilitating
osmosis,which is one of the processes the plant uses for water transport
Any 8 x 1 = 8 marks
b. Describe the mechanisms of ascent of sap in the plant.
(8 marks)
• The cohesion-tension theory explains ascent of sap in the plant
• Pressure gradient between the top and the base of the plant move water through the xylem
by creating tension,
• It is this tension that pulls water up.
• Positive pressure is generated at the base of the plant or negative pressure at the top of the
plant.
• The root can also develop a positive hydrostatic pressure
• However, this is not adequate to move water up a tall tree
• Hence water at the top of a tree develops a large tension (negative hydrostatic pressure) this
tension pulls water through the xylem.
• This pulling requires the cohesive properties of water to sustain the large tensions in the
xylem water columns
8 X 1 marks = 8 marks
c. Explain the mechanism of carbon rescue from photorespiration.
(7 ½ marks)
• Rubisco (ribulose-1,5-biphosphate) can also acts as oxygenase
• When reacting with O2, rubisco produces 2-phosphoglycolate and 3-phosphoglycerate from
ribulose-1,5-biphosphate instead of 2 mol of 3-phosphoglycerates as with CO2
• Process known as photorespiration (O2 inhibition of photosynthesis at low CO2 conc.
• The process rescues the carbon lost as 2-phosphoglycolate by rubisco oxygenase through
three organelles; chloroplast, mitochondrian and peroxisomes
• 2 molecules of 2-phosphoglycolate is transported into peroxisome from chloroplast and
converted to glycine.
• Glycine is exported to mitochondria and loses one carbon as CO2 and transformed to serine.
• Serine is transported to the peroxisome and transformed to glycerate.
• Glycerate latter flows to the chloroplast where it is phosphorylated to 3-phosphoglycerate
and incorporated into the calvin cycle
Any 7 X 1 = 7 = ½ = 7 ½ marks
14
2.
i.
ii.
iii.
iv.
v.
vi.
vii.
viii.
Compare and contrast the following:
Hypertonic and Hypotonic Cells
Cohesion and Tension Concepts
Apoplast and Symplast
Diffusion and bulkflow
Passive and active transport
Photorespiration and Photosynthesis
C3 and C4 plants
C4 Carbon Cycle and Crassulacean Acid Metabolism
(24 marks)
i. Hypertonic and Hypotonic Cells
Both are about solute concentration in relation to water in the cell and water movement across the
cell
Hypertonic: lower water content because of presence of solute, water moves in
Hypotonic: higher water content because of absence or lower conc. of solute, water moves out.
ii. Cohesion and Tension Concepts
Both are involved in ascent of sap
Cohesion: hydrogen bonds between water molecules allow cohesion of water
Tension: Pressure gradient between the top and the base of the plant move water through the xylem
by creating tension, which pulls water up.
iii. Apoplast and Symplast
Both are involved in movement of water across the root from the epidermis to the stellar region
Apoplast: water moves exclusively through cell wall and intercellular spaces without crossing any
transmembranes
Symplast: water travels from one cell to the next via the plasmodesmata.
iv. Diffusion and bulkflow
Both involves movement of molecules e.g. water
Diffusion: is random thermal agitation of molecules and resulting in movement down a
concentration gradient and it is concentration dependent
Bulklow: is the movement of water molecules en masse. It is pressure dependent, as the
movement is down a pressure gradient
v. Passive and active transport
Both involves movement of dissolved solutes and ions across cell membrane
Passive transport: is simple diffusion down a concentration gradient and it does not involve the
use of energy
Active transport: uses energy, it is transport against concentration gradient
vi. Photorespiration and Photosynthesis
Both processes involves the use of ribulose 1,5-biphosphate as acceptor for CO2 and O2
Both processes involves the use of rubisco as enzymes catalyzing carboxylation and oxygenation.
15
Photorespiration: O2 is fixed at low CO2 concentration, 1 mol of phosphoglycerate and 1mol of
phosphoglycolate are formed
Photosynthesis: CO2 is fixed; 2 mol. of phosphoglycerate are formed
vii. C3 and C4 plants
Both are about the first product of dark reactions, either C3 carbon acids or C4 carbon acids
C3 plants: have chloroplasts in just one cell type, the mesophyll; product of carboxylation is a C3
compound, 3-phosphoglycerate; CO2 acceptor in C3 plants is ribulose-1,5-diphosphate
C4 plants: have chloroplasts in mesophyll and bundle sheath; the first stable products are C4 acids,
malate and aspartate; have more efficient photosynthetic machinery than the C3 plants; CO2
acceptor of C4 is phosphoenol pyruvate
viii. C4 Carbon Cycle and Crassulacean Acid Metabolism
Both are about CO2 concentration mechanisms in plants; carboxylation of phosphoenolpyruvate,
malate is produced
C4 Carbon Cycle: carboxylation in the chloroplast at day; vacuole is not involved
Crassulacean Acid Metabolism: carboxylation in the cytosol but at night, storage in vacuole.
3a. Compare glycolysis in plant and animals
5 marks
Answer:
Plant glycolysis has unique regulatory features;
It has a parallel partial glycolytic pathway in plastids;
It also has alternative enzymatic routes for several cytosolic steps;
In animals, the substrate of glycolysis is glucose but because sucrose is the major translocated sugar
in most plants and is therefore the form of carbon that most non-photosynthetic tissues import,
sucrose (not glucose) is the true sugar substrate for plant respiration.
In animals, the end product is pyruvate but the end products of plant glycolysis include another
organic acid, malate.
b. List 10 enzymes involved in glycolysis
10 marks
Answer:
•
Invertase
•
Hexokinase
•
Hexose phosphate isomerase
•
Phospho-fructo-kinase
•
Aldolase
•
Triose phosphate isomerase
16
•
Glyceraldehyde-3-phosphate dehydrogenase
•
Phosphoglycerate kinase
•
Phosphoglycerate mutase
•
Enolase
•
Pyruvate kinase
c. Discuss the fate of pyruvate
8 marks
Answer:
In the presence of oxygen, pyruvate proceeds to Citric acid cycle
In the absence of oxygen, pyruvate either become malate or latate or ethanol
4a. With the aid of a diagram only, describe the Tricarboxylic acid cycle
b. Briefly describe the phases of growth in plant
•
12 marks
6 marks
The period of growth is generally divided into three phases, namely, meristematic, elongation
and maturation. The constantly dividing cells, both at the root apex and the shoot apex,
represent the meristematic phase of growth. The cells in this region are rich in protoplasm,
possess large conspicuous nuclei. Their cell walls are primary in nature, thin and cellulosic
with abundant plasmodesmatal connections.
•
The cells proximal (away from the tip) to the meristematic zone represent the phase of
elongation. Increased vacuolation, cell enlargement and new cell wall deposition are the
characteristics of the cells in this phase.
17
•
Further away from the apex, i.e., more proximal to the phase of elongation, lies the portion
of axis which is undergoing the phase of maturation.
•
The cells of this zone, attain their maximal size in terms of wall thickening and protoplasmic
modifications.
c. Discus the components of classical growth analysis in plants, emphasizing the needed
measurements and units.
5 marks
Two types of measurement are needed for growth analysis.
PLANT WEIGHT: This is usually the oven dried weight (g or kg) or it can be the organic
matter or energy content.
SIZE OF ASSIMMILATORY SYSTEM: This is usually the leaf area (cm2, mm2, m2) but can
also be the leaf protein or chlorophyll content.
For the various components of classical growth analysis (i.e RGR, NAR and LAR) at time (t) (t1,
t2 etc), you need to measure
i. the net gain in dry weight (W). Hence measurement of initial dry weight (W1) and final dry
weight (W2).
ii. the leaf area, the initial (LA1) and final (LA2).
iii.the time (t) at which all these are measured. Hence one can measure the RGR, NAR and
LAR from three parameters: Weight (W), Area (A) and Time (t).
5a. State different causes of physiological innate dormancy
with solutions
8 marks
Seed hardness: hard seed coats, testa or seed covering can serve as barrier to germination and
development of embryo.
SOLUTION
•
i.
Scarification
Chemical Scarification: Use of concentrated inorganic acids, conc. Sulphuric acid, ether and
acetone absolute ethanol, inorganic salt (KMnO4, Na2SO4, NaCl etc).
ii.
Mechanical Scarification: This involves mixing seeds with pebbles, rubbing seeds with sand
paper nipping holes or making punctures.
•
i.
Heat Method
Dry Heat: This involves placing seeds above systems which give out heat. E.g. burning fire
wood
18
ii.
Wet Heat: This involves steaming to break dormancy.
•
Cold Treatment
Chemical inhibitors: presence of chemicals such as coumarine, phenols, abscissic acid etc can cause
dormancy.
•
SOLUTION:
Leaching: Moderate leaching is required to break dormancy and effect germination of seeds. Over
leaching can wash away growth promoters.
Dormancy due to immature embryo: For example Cola nitida, C. millenii.
3.
•
4.
SOLUTION: Storage
Need for Period of Ripening
•
SOLUTION: Storage
Photoblasticity: This is dormancy due to light sensitivity. e.g Ceiba pentandra, Milicia
5.
excelsa, Nicotiana tabaccum etc.
•
SOLUTION: Exposure to day length illumination period of 16hrs or more.
b. Write an essay on the different parts of a germinating seed with respect to the physiological
processes they perform
12 marks
1. Imbibition of water
2. Activation of Precursors of enzymes
3. Production of Amino Acids, Proteins, etc.
4. Mobilization of food materials
c. Classify mineral elements based on their relative concentration in plant tissues with examples
3 marks
•
Macronutrients: Nitrogen, Potassium, Calcium, Magnesium, Phosphorus, Sulphur and
Silicon
•
Micronutrients: Chlorine, Iron, Boron, Manganese, Sodium, Zinc, Copper, Nickel and
Molybdenum.
19
COVENANT UNIVERSITY
CANAANLAND, KM 10 IDIROKO ROAD
P.M.B 1023 OTA, OGUN STATE, NIGERIA
TITLE OF EXAMINATION: B.Sc DEGREE EXAMINATIONS
COLLEGE: SCIENCE AND TECHNOLOGY
DEPARTMENT: BIOLOGICAL SCIENCES
SESSION: 2015/2016
SEMESTER: OMEGA
PROGRAMME: APPLIED BIOLOGY AND BIOTECHNOLOGY
COURSE CODE: BLY 223
COURSE UNIT: 3
COURSE TITLE: BASIC CHORDATE ZOOLOGY
TIME ALLOWED: 2½hrs
INSTRUCTION(S): ATTEMPT FOUR QUESTIONS IN ALL; TWO FROM
EACH SECTION
1a. Discuss the tilapia with special reference on the following:
(i) Taxonomic position of the Tilapia (ii) Feeding Habits (iii) Temperature Tolerance (iv) Growth
1b. Give the general Characteristics of Chondrichthyes
8marks
7marks
1c Class Chondrichthyes has two major groups: Subclass Elasmobranchii (sharks & rays) and
Subclass Holocephali (chimaeras). Give the basic differences between this two group 2½ marks
2a Draw and label elaborately The Ascidian
2b. Give the general characteristics of the chordate
2c. Discuss the classification and reproduction of Balanologuss
8marks
2½marks
7marks
3a Write extensively of the classification of Superclass Osteichthyes up to the order level 5½ marks
3b. Write short notes on the various classes of the Urochordata
6marks
3c Differentiate between the orders of class Agnatha using:
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(i) Characteristics (ii) Habitat (iii) Description (iv) Reproduction
6marks
SECTION B
4a. Define the following terms
(i)
(ii)
(iii)
Amplexus
Toad Balls
Cock
................................. 1 mark
................................. 1 mark
................................. 1 mark
b. Itemize any five orders of class aves with examples ................................. 5½ marks.
c. Highlight any three:
5a.
b.
6a
b
c
d
e
f
major mammalian features
.............. 3 marks
amphibia orders with examples
.............. 3 marks
unique features of the echinoderms
.............. 3 marks
Explain any five actions the Agama lizard is likely to display in its territory
Write extensively on reproduction in pigeons
…10marks
…………………………. 7½ marks
Attempt a correct definition of birds
................................. 1½ marks
What evidences support the belief that birds evolved from reptiles? .............. 3 marks
How are the birds adapted for successful flight?
............................ 4 marks
Four functions that the different feet adaptations in birds may have are
… 2 marks
Do a complete taxonomic classification of yourself
........................ 4 marks
With appropriate examples, what are the three mammalian groups there are? 3 marks
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COVENANT UNIVERSITY
CANAANLAND, KM 10 IDIROKO ROAD
PMB 1023 OTA, OGUN STATE, NIGERIA
TITLE OF EXAMINATION: B.Sc PROGRAMME EXAMINATIONS
SESSION: 2015/2016
SEMESTER: OMEGA
COLLEGE: SCIENCE & TECHNOLOGY DEPARTMENT: BIOLOGICAL
SCIENCES
PROGRAMME: APPLIED BIOLOGY AND BIOTECHNOLOGY
COURSE CODE: BLY223
COURSE TITLE: BASIC CHORDATE ZOOLOGY
COURSE UNIT: 3
1a. Discuss the tilapia with special reference on the following:
Taxonomic Position of the Tilapias (ii) Feeding Habits (iii) Temperature Tolerance
(iv) Growth of Tilapia
8marks
(i)
(i) Taxonomic Position of the Tilapias
ÒTilapiaÓ is the generic name of a group of cichlids endemic to Africa. The group consists of
three aquaculturally important genera Ð OreochromisOreochromis,Sarotherodon and Tilapia.
Several characteristics distinguish these three genera, but possibly the most critical relates to
reproductive behavior. All tilapia species are nest builders; fertilized eggs are guarded in the nest by
a brood parent. Species of both Sarotherodon and Oreochromis are mouth brooders; eggs are
fertilized in the nest but parents immediately pick up theeggs in their mouths and hold them
through incubation and for several days after hatching. In Oreochromis species only females
practice mouth brooding, while in Sarotherodon species either the male or both male and female
are mouth brooders. During the last half century fish farmers throughout the tropical and semitropical world have begun farming tilapia. Today, all commercially important tilapia outside
ofAfrica belong to the genus Oreochromis,
.
(ii) Feeding behavior and nutrition requirements
Tilapia ingest a wide variety of natural food organisms, including plankton, some aquatic
macrophytes, planktonic and benthic aquatic invertebrates, larval fish, detritus, and decomposing
organicmatter. With heavy supplemental feeding, natural food organisms typically account for 30
to 50 percent oftilapia growth. (In supplementally fed channel catfish only 5 to 10 percent of
growth can be traced toingestion of natural food organisms.) Tilipia are often considered filter
feeders because they can efficiently harvest plankton from the water. However, tilapia do not
physically filter the water through gill rakers as efficiently as true filter feeders such as gizzard shad
and silver carp. The gills of tilapia secrete a mucous that traps plankton. The plankton-rich
22
mucous, or bolus, is then swallowed. Digestion and assimilation of plant material occurs along the
length of the intestine (usually at least six times the total length of the fish) The Mozambique tilapia
is less efficient than the Nile or Blue tilapia at harvesting planktonic algae. Two mechanisms help
tilapia digest filamentous and planktonic algae and succulent higher plants: 1) physical grinding of
plant tissues between two pharyngeal plates of fine teeth; and 2) a stomach pH below 2, which
ruptures the cell walls of algae and bacteria. The commonly cultured tilapias digest 30 to 60
percent of the protein in algae; blue-green algae is digested more efficiently than green algae.When
feeding, tilapias do not disturb the pond bottom as aggressively as common carp. However, they
effectively browse on live benthic invertebrates and bacteria-laden detritus. Tilapias also feed on
midwater invertebrates. They are not generally considered piscivorous, but juveniles do consume
larval fish. In general, tilapias use natural food so efficiently that crops of more than 2,700 pounds
of fish per acre (3,000kg/ha) can be sustained in well-fertilized ponds without supplemental feed.
The nutritional value of the natural food supply in ponds is important, even for commercial
operations that feed fish intensively. In heavily fed ponds with little or no water exhange, natural
food organisms may provide one-third or more of total nutrients for growth. In general, tilapia
digest animal protein in feeds with an efficiency similar to that of channel catfish, but are more
efficient in the digestion of plant protein, especially more fibrous materials.
2marks
(iii) Temperature tolerance
The intolerance of tilapia to low temperatures is a serious constraint for commercial culture in
temperate regions. The lower lethal temperature for most species is 50 to 52o F for a few days, but
the Blue tilapia tolerates temperatures to about 48o F. Tilapia generally stop feeding when water
temperature falls below 63o F. Disease-induced mortality after handling seriously constrains
sampling, harvest and transport below 65o F. Reproduction is best at water temperatures higher
than 80o F and does not occur below 68o F. In subtropical regions with a cool season, the number
of fry produced will decrease when daily water temperature averages less than 75o F. After 16- to
20- day spawning cycles with 1/2-pound Nile tilapia, fry recovery was about 600 fry per female
brooder at a water temperature of 82o F, but only 250 fry per female at 75o F. Optimal water
temperature for tilapia growth is about 85 to 88o F. Growth at this optimal temperature is typically
three times greater than at 72o F.
2marks
(iv) Growth
Under good growth conditions, 1-gram fish are cultured in nursery ponds to 1 to 2 ounces (20 to
40 grams) in 5 to 8 weeks and then restocked into grow out ponds. In monosex grow out ponds
under good temperature regimes, males generally reach a weight of ½ pound (200 + grams) in 3 to
4 months, 1 pound (400 + grams) in 5 to 6 months, and 1.5 pounds (700 grams) in 8 to 9 months.
To produce 1-pound (400- to 500-gram) fish, common practice is to stock 6,000 to 8,000 males
per acre in static water ponds with aeration or 20,000 to 28,000 males per acre where 20 percent
daily water exchange is economically practical. After 6 months of feeding with good quality feeds,
such ponds can produce 5,000 to 7,000 pounds per acre and 18,000 to 20,000 pounds per acre,
respectively. If grow out cycles are longer than 5 to 6 months (in an attempt to produce a more
marketable size fillet) there is a risk that offspring from reproduction of the few females that were
unintentionally included in the ‘all-male’ culture will have time to reach sexual maturity and
overpopulate the pond.
2marks
23
1b. Give the general Characteristics of Chondrichthyes
Characteristics of Chondrichthyes:
• cartilaginous skeleton (w/ endoskeletal calcification)
• male intromittent organs (􀀁claspers􀀁)
• placoid scales
• teeth not fused to jaws (only to connective tissue)
• lipid (squalene) filled livers
• fin rays soft and unsegmented (ceratotrichia)
• swim bladder and lung absent
• high concentrations of urea and trimethylamine oxide
(TMAO) in blood (for osmoregualtion)
Any Seven, Each 1mark= 7marks
1c Class Chondrichthyes has two major groups: Subclass Elasmobranchii (sharks & rays) and
Subclass Holocephali (chimaeras). Give the basic differences between this two group 2 ½ marks
Characteristics that separate subclass Chimaeriformes from Elasmobranchs
• Upper jaws attached to braincase (autostylic suspension)
• Single opercular opening, covering 4 gill openings
• All are oviparous
• Separate anal and urogenital opening - no cloaca
• Mostly scaleless
½ mark each= 2 ½ marks
2a Draw and label Elaborately THE Ascidian
8marks
Drawing 3marks
Labeling 5marks
2b. Give the
GENERAL CHARACTERISTICS OF THE CHORDATE
2 ½ marks
24
Give the GENERAL CHARACTERISTICS OF THE CHORDATE.
(i) They have notochord at one time of the life cycle or throughout life.
(ii). They have dorsal hollow nerve cord.
(iii). They have pharyngeal gill slits.
(iv). They possess myomere or muscles sheaths.
(v). they have post anal tail.
2c. Discuss the classification and reproduction in Balanologuss .
2 ½ marks
7marks
CLASSIFICATION
The Hemichordata includes about 80 known species and a very few fossil species. The adult form of one
class is yet not known. It is divided into four classes.
CLASS 1: ENTEROPNEUSTA
1. Solitary worm-like burrowing animals commonly known as acorn or tongue worm. 2. Body elongated
and vary from moderate to great length. 3. The epidermis is ciliated and glandular. 4. The digestive tract
is straight with a terminal anus. 5. There are numerous paired U-shaped gill slits. 6. Sexes separate and
gonads numerous, sac-like. 7. Development generally includes a free swimming tornaria larva Examples:
Balanoglossus, Saccoglossus (=Dolichoglossus), Ptychodera. Saccoglossus Saccoglossus is almost world
wide in distribution. The smallest known species of Enteropneusta is Saccoglossus pygmaeus which
measures about 2–3 cm in length. Saccoglossus is similar to Balanoglossus is habits, habitat and
structure. It lives in spirally twisted burrows. The proboscis of this animal is exceptionally long and
pointed. The collar slightly overhangs the anterior part of the trunk covering first 3-4 pairs of gill slits.
The hepatic caecae and genital wings are absent. The gonads are marked externally by dorso-lateral
genital folds. Sexes are separate, fertilization is external and development is direct. CLASS 2:
CLASS 2: PTEROBRANCHIA
1. They are sedentary, solitary or colonial, tubicolous animals living in secreted chitinous tubes. 2. Body
is short, compact and with a stalk for attachment. 3. Proboscis is shield-shaped. 4. Collar bears hollow
ciliated arms with tentacles called lophophores. They are meant to produce ciliary feeding currents of
water. 5. Gill slits two or absent. 6. Alimentary canal U-shaped. Mouth and anus situated close to each
other. 7. Sexes separate or hermaphrodite, gonads one or two. 8. Development direct or indirect. 9.
Asexual reproduction by budding.
Order 1: Rhabdopleurida 1. Form true colonies, the individuals of a colony are connected by a stolon. 2.
Collar bears a pair of tentaculated arms. 3. Gill slits are absent. 4. Gonad single.
Order 2: Cephalodiscida
25
1. Solitary or aggregation of several zooids not connected with each other but housed in a common
gelatinous encasement. 2. Collar bears several tentaculated arms. 3. Gill slits and gonads single pair.
Class 3: Graptolita 1.
Includes extinct colonial hemichordates. 2. Known from the fossil structure of their tubes. 3. They were
found in the Ordovician and Silurian period. Example: Dendrograptus.
Class 4: Planctosphaeroidea
1. They are known only by round, transparent pelagic larva related to tornaria. 2. The adult form is yet
not known. 3. The alimentary canal of the larva is U-shaped. 4. Branching ciliated bands are present on
the aboral surface of the larva. Example: Planctosphaera
Classification 4mark
Fertilization occurs in the water and forms a feeding planktonic larva – Tornaria
3marks
3a Write extensively of the
Superclass: Osteichthyes up to the order level
3b. Write short notes on the various classes of the Urochordata
Reproduction
classification of
5 ½ marks
6marks
26
Urochordates do not have a backbone but share our phylum, because during a stage in their life
cycle they have a primitive notochord. The y are represented in the plankton by three main
classes.
CLASS ASCIDIACEA
A common Ascidacean is the sea squirt, which is typically found on the seabed or attached to
the bottom of ships. It has a larval stage called an Ascidian tadpole (as it superficially resembles
a frog tadpole) which often occurs in plankton samples.
2marks
CLASS LARVACEA
Larvaceans, also known as appendicularia, have an elongated, flat paper- like body of varying
width. They have a “head” which usually appears to be very loosely attached to the body and is
often broken off in samples. They secrete a jelly- like “house” inside which they live, but the
house and animal are generally sampled separately when they are caught in the plankton net.
2marks
CLASS THALIACEA
There are two main groups of thaliaceans. The doliolids are barrel-shaped and have complete
and separate circles of muscle-bands around the body e.g. Doliolum. They have a complex life
history involving three stages, apart from the larvae. One of the stages is sometimes found in a
disintegrating form (old nurse), where the individual becomes very flabby and the muscle band
widen till they can become continuo us in some species.
2marks
The second groups, the salps, are generally larger than doliolids and have more jelly in their
bodies. In salps, some of the muscle bands join together at certain points and do not go completely
round the body e.g. Thalia. They have a less complex life cycle than dolioids. The asexual
individuals live singly and are called solitary. They bud off sexual individuals in a chain, which stick
together for some time, so are called the aggregate phase.
3c Differentiate between the orders of class Agnatha using:
(i)
Characteristics (ii) Habitat (iii) Description (iv) Reproduction
6marks
(i) Characteristics - Hagfish

Have large numerous mucus pores

Have 70 – 200 pairs of slime glands

Mucus function is not completely understood

The hagfish ties itself in an overhand knot to rid itself of the slime

Leather made of “eel skin” are sometimes made from hagfish
Characteristics - Lamprey

Latches on sides of fish sucking blood and body juices (lymph)
27

Some species are more predatory than others removing bone and organs
1 ½ marks
ii) Habitat -Hagfish
(ii)
It is found in the Atlantic Ocean.
(iii)
And it goes down to 4,000 feet.
Habitat - Lamprey
 Lampreys are found only in the Mediterranean and North Atlantic.
 in the coastal seas off the North East USA, Nova Scotia, southern Greenland, the UK,
Ireland and Scandinavia.
 They are also found in the Great Lakes and enter inland freshwater rivers and streams
to breed.
 In their natural habitat, sea lampreys lives in the open ocean, migrating into freshwater
to spawn.
 The larvae live in soft stream sediments
1 ½ marks
(iii) Description---- Hagfish
•
It is believed that this slime can actually suffocate predators by clogging their gills if they
come in contact with it.
•
Believe it or not the Hagfish uses its own slime to protect itself from predators.
It can also be used to produce a protective cocoon for the Hagfish
(iii) Description--- -- lamprey

2 separate dorsal fins with a maximum size of 47”

Distinct oral disc with tooth like plates of keratin on eversible tongue

Seven pairs of gill openings on each side of the head, lacks paired fins

Unlike hagfish, have well-developed eyes
1 ½ marks
(iv) Reproduction - hagfish

Both ovaries and testes are present but only one is functional

Female lays large sausage shaped (2-3cm.) eggs, numbering 20-30
Reproduction - lamprey


Anadromous migration
Also, have both reproductive organs but only one is functional
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
4a
4b
4c
Male creates nest with stones, and female spawns up to 124,000-260,000 eggs
1 ½ marks
SECTION B
Amplexus – Mating position
Toad Boals - Many male toads climbing on one another in seeking for mating partner
Cock – The dominant male lizard in a territory
..................... 3 marks
Order Anseriformes – Ducks
Order Apodiformes – Hummingbirds
Order Caprimulgiformes – Whippoorwills
Order Charadriiformes – Gulls
Order Ciconiiformes – Sorks, Herons
Order Columbiformes – Doves and Pigeons
Order Coraciiformes – Kingfishers, Rollers, Bee eaters
Order Cuculiformes – Cuckoos
Order Falconiformes – Hawks, Eagles and Falcons
Order Galliformes – Turkeys, Chickens and Pheasants
Order Passeriformes – Mocking birds, Swallows
Order Pelecaniformes – Pelecans
Order Piciformes – Wood peckers
Order Podicipediformes – Grebes
Oder Procellariiformes – Albatross
Order Psittaciformes – Parrots and Parakeets
Order Strigiformes – owls
Order Struthioniformes – Ostrich
.............. Any 5 = 5 marks
(i) Mammals have integumentary/sweat glands, hair/fur and have mammary glands 3 marks
(ii)
Apoda – Frogs and Toads
Anura – Caecilian woms
Urodela – Salamander and Newts
(iii)
3 marks
3½ bonus marks
5a
The head nod is when A. agama repeatedly raises and lowers his head, usually seen at the end of
movements, possibly to show cock position of individuals.
29
Head bobbing, also known as push-ups, is the raising and lowering of the head and chest. This is
done in an alert posture, it also occurs in the reproductive behavior of the cock. Shown to females
when in reproductive colors, one to two begins courtship.
The challenge display is shown by the cock to intruding males or sub-males showing reproductive
color. This is only seen in territory situations.
The threat display is the rapid up and down movement of the head with the gular sac fully extended.
The whole body raises and lowers.
Fighting is a series of bluffs, threats and combat. The challenge occurs when a sub-male or intruding
male of reproduction color comes into a territory
Basking occurs mainly in the morning between ten and noon, when A. agama has a darker dorsal
coloration than later in the day
…………. 1½ marks each, 7½ marks
b
Males and females reach sexual maturity within an average of 140 days. Most species of pigeon are
monogamous, a single male breeds with a single female during the breeding season. Courtship
behaviors that lead to mating in many species involve flight displays. In pigeons, males perform a
“bow-coo” display involving cooing and bowing just before mating. Pairs may be formed at any point
during the year. These pairs are formed for life. Pigeons build a nest of sticks, straw and other
materials. The male collects nesting materials and pass it to the female who tucks it around her body.
Pairs are territorial and defend their nesting areas from other members of the species. In most
species, females lay two eggs at a time. In a few species, only one egg is laid. In many species, both
parents share incubation duties; with the males incubating, sitting on the nest from morning to
afternoon and females incubating from afternoon to the next morning. Eggs hatch about 19 days
after being laid. The eggs are altricial, hatching at an early developmental stage, blind and with few
or no feathers. For the first few days, pigeons feed their young crop milk, a fatty substance produced
in the crop, an organ located in the throat
.………….. 10 marks
6a Birds are reptile-like animals that maintain a constant internal body temperature ... 1½ marks
6b
Embryos of birds and reptiles develop within amniotic eggs
Both excrete nitrogenous wastes as uric acid.
Bones that support the limbs, and other skeleton parts, are similar in both groups ..3 marks
6c
highly efficient digestive, respiratory, and circulatory systems
aerodynamic feathers and wings
30
strong, lightweight bones
strong chest muscles
.......................4 marks
6d
Grasping, perching, walking, climbing, swimming
6e
Kingdom
Phylum
Subphylum
Class
Order
Family
Genus
Species
6f
….... 2 marks
Animalia
Chordata
Vertebrata
Mammalia
Primates
Hominidae
Homo
sapiens
..................... 4 marks
Prototherians (monotremes); Metatherians (marsupials); Eutherian (placentals) ........ 3 marks
31