2012 Flashcards
- Which of the following is NOT a defining feature of chordates?
a. Ventral nervous system
b. Ventral heart
c. Gills at some stage of life
d. A tail extending past the anus
e. A notochord
a. Ventral nervous system
- Which of the following physiological responses is an example of a negative feedback response loop?
a. An increase in the concentration of glucose in the blood stimulates the pancreas to secrete insulin, a hormone that lowers blood glucose concentration
b. Stimulation of a nerve cell causes sodium ions to leak into the cell, and the sodium influx triggers the inward leaking of more sodium
c. During childbirth, the baby’s head against the cervix causes an increase in plasma oxytocin concentration
d. Blood clot formation
e. Salivary glands activated at the sight of food
a. An increase in the concentration of glucose in the blood stimulates the pancreas to secrete insulin, a hormone that lowers blood glucose concentration **
- The fish tank below indicates a negative feedback response loop in terms of water temperature.Which letter correctly identifies the effector in this scenario?
- A & G
- C
- G, B & D
- All except A
C **
- The opposite diagram is BEST
described as ______________________ .
a. Positive feedback
b. Homeostasis
c. Negative feedback
d. Feed forward control
e. Feed backward control
Negative feedback**
- Match the cell membrane transport processes indicated in the diagram BELOW with their correct description.
1
4
3
2
Membrane structure
Transport process
a.
1
None
facilitated diffusion
b.
2
None
active transport
c.
2 & 3
Transport protein
active transport
d.
4
Transport protein
active transport
e.
4
Transport protein
facilitated diffusion
d.
4
Transport protein
active transport **
- Which of the following change shape in response to the presence of specific molecules in order to transport those molecules across the cell membrane?
a. Structural proteins
b. Enzymes
c. Carrier proteins
d. Channel proteins (eg aquaporins)
e. Ligands
c. Carrier proteins
- The Na-K ATPase pump moves ______ Na+ molecule(s) out of a cell and ______ K+ molecule(s) into a cell per ______ molecule(s) ATP hydrolysed.
a. One One One
b. One Two Three
c. Two Three One
d. Three Two One
e. Three Three One
d. Three Two One
- Which of the following BEST distinguishes between osmolarity and tonicity?
a. Osmolarity is a passive process but tonicity involves active transport
b. Osmolarity is only of concern in the present of salt
c. Tonicity takes into account only non-penetrating solutes
d. Tonicity is affected by the concentration of the permeable solutes
e. Tonicity is given in absolute values
c. Tonicity takes into account only non-penetrating solutes
- Which ONE of the following BEST defines connective tissues as a group?
a. They are typically acellular
b. They connect other structures, e.g. muscle to bone
c. They are predominantly composed of extracellular matrix
d. They are derived from the embryonic mesoderm
e. They have a poor blood supply
c. They are predominantly composed of extracellular matrix
- In the tube illustrated BELOW, fluid is flowing into the tube (at the point indicated by the arrow) at a flow rate of 2 L per minute.Three points along the tube are labelled 1, 2 and 3.Which ONE of the following is a CORRECT statement about the movement of fluid in this tube?
- Fluid flow will be highest at Point 2
- Both fluid flow and fluid velocity will be lowest at Point 2
- Both fluid flow and fluid velocity will be highest at Point 2
- Fluid velocity will be highest at Point 3
- Fluid velocity will be the same at Points 1, 2 and 3
- Fluid velocity will be highest at Point 3
- Which of the following statements is FALSE for the main solutes in vertebrates?
a. Perturbing solutes disrupt macromolecule function
b. Na+, K+, Cl-, SO4+ and charged amino acids are disrupting solutes
c. Compatible solutes have little affect on macromolecule function
d. Polyols (e.g. glycerol, glucose) and uncharged amino acids are compatible solutes
e. Counteracting solutes disrupt function only when in combination with other solutes (e.g. urea and methylamines)
e. Counteracting solutes disrupt function only when in combination with other solutes (e.g. urea and methylamines)
- Select the option that CORRECTLY ranks these vertebrate diets from least to most preformed water
least preformed water
↔
most preformed water
a.
Green pasture
Dry grass
Meat
b.
Green pasture
Insects
Dry grass
c.
Dry seeds
Insects
Green pasture
d.
Dry seeds
Green pasture
Dry grass
e.
Nectar
Meat
Insects
c.
Dry seeds
Insects
Green pasture **
- The following list indicates the main nitrogenous waste for each vertebrate group (although there are some exceptions to this rule).Which pair is INCORRECT?
Vertebrate group
main nitrogenous waste
a.
Teleosts (bony fish)
ammonia and urea
b.
Chondrichthyes (cartilaginous fish)
urea
c.
Amphibians
ammonia, urea and uric acid
d.
Birds and reptiles
uric acid
e.
Mammals
uric acid
e.
Mammals
uric acid
- A marine fish (a maintains water and electrolyte balance by retention of ____________ , the perturbing effects of which are counteracted by the presence of____________ .
a.
Electrolytes
Urea
b.
Electrolytes
TMAO (trimethylamine oxide)
c.
Urea
TMAO (trimethylamine oxide)
d.
Urea
Rectal glands
e.
Electrolytes
Rectal glands
c.
Urea
TMAO (trimethylamine oxide) **
- Alcohol and caffeine inhibit Antidiuretic hormone (ADH) secretion from the pituitary. Select the option that BEST describes the consequences of inhibited ADH secretion.
a. Small volume of concentrated urine will be produced
b. Small volume of dilute urine will be produced
c. Large volume of concentrated urine will be produced
d. More aquaporins (water channels) will be inserted into the renal collecting ducts
e. The renal collecting ducts will remain impermeable to water
e. The renal collecting ducts will remain impermeable to water
- The diagrams below show two types of nephron in the mammalian kidney.Choose the option that does NOT accurately describe the differences between these two nephron types.
a.
‘Cortical’ nephron
‘Juxtamedullary’ nephron
b.
Located primarily within the cortex of the kidney
A large proportion of the nephron present in the medulla of the kidney
c.
Short loops of Henle
Long loops of Henle
d.
Produce relatively dilute urine
Produce the medullary osmotic gradient
e.
More pronounced (greater proportion of the nephrons) in species adapted to arid environments
Less pronounced (smaller proportion of the nephrons) in species adapted to arid environments
e.
More pronounced (greater proportion of the nephrons) in species adapted to arid environments
Less pronounced (smaller proportion of the nephrons) in species adapted to arid environments**
- There are three main types of cartilage, hyaline cartilage, fibrocartilage, and elastic cartilage.Which of the following BEST describes these types?
Hyaline cartilage
Fibrocartilage
Elastic cartilage
a.
smooth and firm, found between articular joints
high tensile strength, found within intervertebral discs
highly elastic, found within the ear cartilage
b.
soft and spongy, found in all extracellular matrices
low tensile strength, found within nose cartilage
highly elastic, found within the ear cartilage
c.
soft and spongy found within intervertebral discs
smooth and firm, found between articular joints
highly elastic, found within the contractile sarcomere of the muscle
d.
smooth and firm, found within intervertebral discs
soft and spongy, found between articular joints
highly elastic, found within the ear cartilage
e.
None of the above
a.
smooth and firm, found between articular joints
high tensile strength, found within intervertebral discs
highly elastic, found within the ear cartilage**
- Which of the following is NOT TRUE about type I collagen?
a. it is the most abundant protein in the mammalian body
b. it best resists tensile forces
c. it is secreted from the cell as procollagen which then assembles spontaneously
d. it is the major component of skin dermis
e. it resists hydrophilic expansion of aggrecan in articular cartilage
e. it resists hydrophilic expansion of aggrecan in articular cartilage
- Which of the following tissue properties is UNIQUE to bone?
a. its major component by weight is inorganic mineral
b. its major component by weight is extracellular material
c. it is resistant to compression
d. it has a very low water content
e. it contains multinucleate cells
a. its major component by weight is inorganic mineral
- The term sarcomere is BEST defined as:
a. one set of actin and myosin filaments
b. the smallest functional contractile unit of a myofibril
c. a serially-repeating unit of a myofilament
d. the width of a Z-disc
e. the optimal myofibril length on the tension-length curve
b. the smallest functional contractile unit of a myofibril
- Which ONE of the following is a CORRECT statement about current flow in a nerve axon?
a. Increasing axon diameter decreases passive current flow along the axonal cytoplasm
b. Myelin decreases current leakage across the axonal membrane
c. Increasing axon diameter decreases current leakage across the axonal membrane
d. Current leakage across axonal membranes is lowest at the Nodes of Ranvier
e. Myelin decreases passive current flow along the axonal cytoplasm
b. Myelin decreases current leakage across the axonal membrane
- Which ONE of the following defines the adequate stimulus of a sensory receptor?
a. The threshold at which a generator potential is produced
b. The speed with which the generator potential is produced
c. The size of the receptive field that is detecting the stimulus
d. The modality to which the receptors responds best
The process involved in sensory transduction
d. The modality to which the receptors responds best
- Which ONE of the following is involved in the brain “recognising” the intensity of a mechanical stimulus applied to the skin?
a. The amplitude of action potentials in sensory nerves is greater for more intense stimuli
b. The frequency of action potentials in sensory nerves is greater for more intense stimuli
c. There are specific sensory receptors that detect different intensities of mechanical stimuli
d. There are specific areas in the brain that receive different intensities of mechanical stimuli
e. The neurotransmitter released from afferent neurons differs with stimuli of differing intensities
b. The frequency of action potentials in sensory nerves is greater for more intense stimuli
- The conduction of sound waves from the middle ear to the inner ear is associated with which ONE of the following?
a. Transmission through the Organ of Corti
b. Vibration of the stapes (stirrup) against the round window
c. Vibration of the stapes (stirrup) against the oval window
d. Vibration of the malleus (hammer) against the stapes (stirrup).
e. Vibration of the incus (anvil) against the tympanic membrane
c. Vibration of the stapes (stirrup) against the oval window
- Which ONE of the following skin receptors would be involved in detecting an infection associated with a splinter of wood in the tip of a finger?
a. Merkel’s disks
b. Ruffini’s corpuscles
c. Meissner’s corpuscles
d. Thermoreceptors
e. Nociceptors
e. Nociceptors
- Which ONE of the following is a function of the fluid in the anterior chamber of the eye?
a. Provide nutrients to the sclera
b. Provide nutrients to the cornea and lens
c. Help focus light on the retina
d. Directs light through the pupil
e. Maintain the blood supply to the ciliary body
b. Provide nutrients to the cornea and lens
- The saccule detects movement in which ONE of the following directions?
a. Angular acceleration, as when nodding the head “yes”
b. Angular acceleration, as when shaking the head “no”
c. Angular acceleration, from side to side
d. Linear acceleration forward and backward
e. Linear acceleration up or down
e. Linear acceleration up or down
- Which ONE of the following is detected by Type II taste receptor cells?
a. Salty
b. Sweet and umami**
c. Umami and salty
d. Sweet and sour
e. Bitter
e. Bitter
- In aquatic animals, which ONE of the following is a function of neuromasts?
a. Prey location by electrodetection
b. Navigation by magnetodetection
c. Detection of movement through water
d. Detection of sound in water
e. The production of an electrical field around the animal
c. Detection of movement through water
- The following graph shows the relationship between the rate of a biochemical reaction (e.g. enzyme activity) and temperature.Which of the following statements is CORRECT regarding this biochemical reaction?
- The rate of this reaction is independent of temperature
- The rate of this reaction can be described as having a Q10=1
- The rate of this reaction can be described as having a Q10=2
- The rate of this reaction can be described as having a Q10=3
- Biochemical reactions should not be affected by temperature
The rate of this reaction can be described as having a Q10=2
- The graph below shows the body temperature (Tb) and metabolic rate (M) of a hypothetical___________________ .
- Homeotherm
- Heterotherm
- Poikilotherm
- Ectotherm
- Stenotherm
- Poikilotherm
- In terms of thermoregulatory strategy, reptiles are best described as
a. Endothermic homeotherms
b. Endothermic poikilotherms
c. Endothermic heterotherms
d. Ectothermic homeotherms
e. Ectothermic poikilotherms
e. Ectothermic poikilotherms
- The slope of the portion of the graph marked with the bracket is influenced by _______________ .
a. Conductance of heat to the environment
b. The animal’s body temperature
c. The amount of insulation the animal has
d. Body size
e. All of the above
e. All of the above
- Which BEST identifies the temperature range that is this animal’s thermoneutral zone?
a. Temperatures colder than A
b. Temperatures between A and B
c. Temperatures between B and C
d. Temperatures between C and D
e. Temperatures hotter than D
c. Temperatures between B and C
- Which of the following options CORRECTLY identifies advantages and disadvantages of blubber vs. fur?
Fur
Blubber
a.
Fur loses its thermal insulation when wet
Blubber loses its thermal insulation when wet
b.
The properties of fur work best when the animal is wet
The properties of blubber work best when the animal is wet
c.
The thermal insulation of fur can be bypassed when the animal is cold
The thermal insulation of blubber can be bypassed when the animal is cold
d.
The thermal insulation of fur cannot be bypassed when the animal is hot
The thermal insulation of blubber can be bypassed when the animal is hot
e.
There is no limit on how long fur can grow to be
There is no limit on the thickness of the blubber layer
d.
The thermal insulation of fur cannot be bypassed when the animal is hot
The thermal insulation of blubber can be bypassed when the animal is hot **
- Which of the following is the BEST description for essential nutrients?
a. Those required for body maintenance
b. Those that must be supplied by the diet
c. Those that can be synthesised by the body
d. Those required for protein deposition
e. Those required for anabolism
b. Those that must be supplied by the diet
- Which of the following correctly orders these nutrients from greatest amounts required to least amounts required?
Greatest
ßà
Least
a.
Carbohydrates
Minerals
Fat
b.
Carbohydrates
Fat
Protein
c.
Carbohydrates
Vitamins
Protein
d.
Protein
Vitamins
Fat
e.
Protein
Vitamins
Water
b.
Carbohydrates
Fat
Protein **
- In vertebrates, the digestion of cellulose _________ .
a. is due to secretion of acid in the stomach
b. is due to the action of amylases
c. is due to the action of disaccharidases
d. is due to the action of microorganisms in the gut
e. takes place in all species
d. is due to the action of microorganisms in the gut
- The following diagram illustrates the digestive system of a kangaroo. Which of the following statements are CORRECT?
a. Kangaroos are foregut fermenters
a. Kangaroos are hindgut fermenters
b. Kangaroos are ruminants
c. Kangaroos do not have the capacity to digest cellulose
d. Kangaroos have a short gut to allow them to hop
a. Kangaroos are foregut fermenters
- Which of the following is a correct illustration of an anabolic process?
a. Breakdown of fats to fatty acids
b. Breakdown of proteins to amino acids
c. Breakdown of complex carbohydrates to monosaccharides
d. Synthesis of proteins from amino acids
e. Synthesis of polysaccharides from fatty acids
d. Synthesis of proteins from amino acids
- Which of the following is correct during the absorptive state?
a. Glucose is released from food in the gut
b. Glucose is released from the liver
c. Triglycerides are broken down to provide energy for the body
d. Proteins are broken down to provide energy for the body
e. Glucagon is broken down to provide energy for the body
a. Glucose is released from food in the gut
- During the post-absorptive (fasted) state, __________ is the dominant hormone and the body undergoes net __________ .
a. Glucagon catabolism
b. Glucagon energy storage
c. Insulin anabolism
d. Insulin growth
e. Insulin energy storage
a. Glucagon catabolism **
- Which of the following statements is FALSE?
Action
Consequence
a.
Increase in blood glucose
Circulating insulin increases
b.
Cells around body take up glucose
Fall in blood glucose concentration
c.
Decrease in blood glucose
Circulating glucagon increases
d.
Circulating glucagon increases
Breakdown of glycogen in liver
e.
Glycogen is released from liver
Decreased blood glucose
e.
Glycogen is released from liver
Decreased blood glucose **
- Which of the following options CORRECTLY identifies the circulating and storage form of each of these fuels for metabolism?
Metabolic fuel
Circulating form
a.
Carbohydrate
Glucose
b.
Carbohydrate
Glucagon
c.
Protein
Carbohydrate
d.
Protein
Fatty acids
e.
Fat
Amino acids
a.
Carbohydrate
Glucose**
- In which of the following would you record the LOWEST metabolic rate?
a. A young, 20kg dog recovering from injury
b. A young, 20kg dog in a cold room
c. An old, 20kg dog on a treadmill
d. An old, 20kg dog in a warm room
e. An old, 20kg dog in a cold room
d. An old, 20kg dog in a warm room
- Which ONE of the following best describes the muscle mechanics involved in quiet expiration?
a. Contraction of the diaphragm and external intercostal muscles leads to a decrease in thoracic volume
b. Relaxation of the abdominal and internal intercostals muscles leads to a decrease in thoracic volume
c. Relaxation of the diaphragm and external intercostal muscles leads to a decrease in thoracic volume
d. Contraction of the abdominal and internal intercostal muscles leads to a decrease in thoracic volume
e. Relaxation of the diaphragm and external intercostal muscles leads to an increase in thoracic volume
c. Relaxation of the diaphragm and external intercostal muscles leads to a decrease in thoracic volume
- Which ONE of the following sets of variables will speed up the rate of gas diffusion from the alveoli to the blood?
a. Increased surface area, decreased diffusion distance, higher gas solubility coefficient
b. Decreased diffusion distance, decreased partial pressure gradient, higher gas solubility coefficient
c. Increased diffusion distance, increased partial pressure gradient, higher gas solubility coefficient
d. Increased surface area, decreased diffusion distance, lower gas solubility coefficient
e. Decreased diffusion distance, increased partial pressure gradient, lower solubility coefficient
a. Increased surface area, decreased diffusion distance, higher gas solubility coefficient
1.Which ONE of the following is a TRUE statement regarding avian respiration?
a. Inspiration relies on contraction of the diaphragm and external intercostal muscles
b. Avian lungs have a greater capacity to expand than mammalian lungs
c. Gas exchange takes place at the numerous air sacs throughout the body
d. Airflow through avian lungs is unidirectional
e. Parabronchi directly connect the caudal and cranial air sacs, bypassing the lungs
- Airflow through avian lungs is unidirectional
- Which ONE of the following sets of changes would you expect to see in the arterial partial pressure of CO2 (pCO2 ) and O2 (pO2) during hypoventilation?
a. A decrease in both pCO2 and pO2
b. An increase in both pCO2 and pO2
c. A decrease in pCO2 and an increase in pO2
d. An increase in pCO2 and a decrease in pO2
e. No change to either pCO2 or pO2
d. An increase in pCO2 and a decrease in pO2
- Which ONE of the following is a TRUE statement regarding the function of intrapleural fluid?
a. Reduces hydrogen bonds in the alveoli, allowing their expansion during inspiration
b. Increases hydrogen bonds between the pleural layers, preventing separation of the pleurae
c. Reduces hydrogen bonds between the pleurae, holding the lungs in a semi-inflated state at rest
d. Reduces hydrogen bonds between the pleural layers, ensuring friction free movement of the lungs against the thoracic wall
e. Increases hydrogen bonds in the alveoli, preventing them from collapsing
b. Increases hydrogen bonds between the pleural layers, preventing separation of the pleurae
- A sealed 2 litre (2L) container has a mixture of gases contained in it at a pressure of 500 mmHg. If the volume of the container is halved to 1 litre (1L), what would expect the new pressure in the container be (assume ideal conditions)?
a. 1000 mmHg
b. 250 mmHg
c. 500 mmHg
d. 50 mmHg
e. Unable to judge because the type of gas is not specified.
a. 1000 mmHg
- Which ONE of the following is a TRUE statement regarding transpulmonary pressure (Ptp)?
a. Remains constant throughout inspiration and expiration
b. Represents the pressure within the intrapleural space and is always negative
c. Increased Ptp creates a larger distending force necessary for lung expansion
d. Represents the force that keeps the lungs distended and is always negative
e. Represents the pressure within the intrapleural space and is always positive
c. Increased Ptp creates a larger distending force necessary for lung expansion
1.Which ONE of the following is characteristic of the respiratory zone?
a. Absence of goblet cells and cilia, increased mucous production
b. Airways 1-2mm in diameter, absence of mucous, cilia and cartilage
c. Absence of cartilage, increased total cross-sectional area of zone
d. Increased membrane thickness, absence of mucous, cilia and cartilage
e. Decreased membrane thickness and reduced total cross-sectional area of zone
<>c.Absence of cartilage, increased total cross-sectional area of zone
1.Which cells are responsible for producing surfactant?
a. Goblet cells
b. Type I alveolar cells
c. Type II alveolar cells
d. Alveolar macrophages
e. None of the above
- Type II alveolar cells
- Which ONE of the following is a TRUE statement regarding air pressure and altitude?
a. As altitude increases, the partial pressure of oxygen decreases
b. As altitude increases, the density of air increases
c. As altitude decreases, the partial pressure of oxygen decreases
d. As altitude increases, the partial pressure of carbon dioxide increases
e. As altitude decreases, the partial pressure of oxygen remains unchanged
a. As altitude increases, the partial pressure of oxygen decreases
- Complete EACH of the sentences below by choosing ONE CORRECT alternative from the following options:
Associated proteins
Cholesterol
Integral proteins
Phospholipids
Glycocalyx
a. Polar ____________________________________________ can move laterally in the plasma membrane, but cannot flip.
b. Ion channels are a type of _________________________________________________
c. Membranes that contain higher levels of _______________________ are more flexible.
d. Transporters are one example of ___________________________________________
Phospholipids;
integral protein;
cholesterol;
integral protein
Although there are very many types of cells, they form only a very limited set of tissue types. State the FOUR main types of tissues that are found within vertebrates (ignoring the potential 5th category of ‘round cells’). For each of the four tissues types, give a specific, named example of that tissue and state a location and function of that tissue
E___________
Tissue type
Specific example
Location
Function
Epithelium
Could be epidermis, liver cells, kidney tubules, exocrine or endocrine glands (sweat, pancreas, sebaceous, thyroid, islets of Langerhans etc), gut lining, respiratory lining etc
Interfaces between compartments, and glands (skin, lining hollow organs e.g. gut, glands (liver, pancreas, sweat etc), kidney tubules etc
Barrier between body compartments or internal /external environments. Protection, exchange, transport, secretion, ciliated, depending on example selected
Although there are very many types of cells, they form only a very limited set of tissue types. State the FOUR main types of tissues that are found within vertebrates (ignoring the potential 5th category of ‘round cells’). For each of the four tissues types, give a specific, named example of that tissue and state a location and function of that tissue
C____________
Connective tissues
Bone
Cartilage
Fat
Collagen
Any named bone
Articular surface, growth plate, nasal cartilage, tracheal or bronchial rings, ear, larynx, epiglottis
Subcutaneous or internal depots
Tendons, dermis, supporting stroma of various organs
Generally connect, anchor, support etc, but cartilage can be lubricating, allow growth etc, fat has metabolic roles (energy storage) plus insulation and contouring. Collagen specialised for tensile strength, also in wound repair etc
Although there are very many types of cells, they form only a very limited set of tissue types. State the FOUR main types of tissues that are found within vertebrates (ignoring the potential 5th category of ‘round cells’). For each of the four tissues types, give a specific, named example of that tissue and state a location and function of that tissue
M__________________
Muscle
Cardiac muscle
Skeletal (or striated)
Smooth muscle
Heart
Biceps
Small intestine wall
Contract/generate force (applies to all)
Spontaneous contraction to pump blood
Contract to flex elbow
Mix and propel food
Any named muscle is fine.
As well as skeletal muscles that move bones relative to one another, there are the diaphragm and extraocular eye muscles which could be good answers also
Smooth muscle is also found in blood vessels (resistance), hairs (erect the hairs), uterus wall, gall bladder wall etc
Any comment that relates to named muscle is fine, including move joint, run, locomotion, etc depending on example of muscle chosen.
Depends on example chose
Although there are very many types of cells, they form only a very limited set of tissue types. State the FOUR main types of tissues that are found within vertebrates (ignoring the potential 5th category of ‘round cells’). For each of the four tissues types, give a specific, named example of that tissue and state a location and function of that tissue
N_______________
Nervous
Neuron
Astrocyte
Oligodendrocyte
Peripheral nerve
Schwann cells
Brain, retina, spinal cord, peripheral nerves and various autonomic ganglia are the most likely examples to be given
Initiate, transmit, integrate electrical impulses. Insulate nerve (oligodendrocyte or Schwann cell) Use judgement according to example chosen
Supports CNS cells, various metabolic roles, blood brain barrier
Makes myelin in CNS, insoulates electrically
Afferent and/or efferent conduction of impulses/axon potentials
Myelinate PNS, electrical insulation
a. What is the main change to cardiovascular function that occurs in the HUMAN dive reflex (as observed in your practical class)?
Decreased heart rate (diving bradycardia)
b. Briefly describe ONE OTHER change to heart and/or cardiovascular function that occurs as part of the dive reflex in mammals adapted for regular diving (e.g. elephant seals).
Increased peripheral resistance: Constriction of blood vessels to all organs except heart, brain, eyes, lungs. (Helps to maintain BP in face of drop in heart rate and therefore cardiac output).
OR
Mobilisation of RBCs from spleen before and during dive: Increases O2 carrying capacity of blood (taken up again on surfacing to decrease problems associated with more viscous blood)
(In lecture also mentioned that seals enter hypometabolic state: e.g. glide rather than swimming, decreases O2 requirements, but not strictly reflex. Seals also have higher levels of myoglobin to store O2 in muscles, but again this is an ongoing adaptation and not part of the reflex. No marks for either of these.)
One special property of flow in the cardiovascular system is that blood viscosity is variable. In the space below, briefly explain TWO factors that contribute to the variable viscosity of blood
Factor 1
(1) Blood viscosity depends on haematocrit: RBCs level is a major determinant of blood viscosity, as RBC number increases so does viscosity. May mention pathological situations in which blood viscosity is too high (polycythaemia) or too low (anemia).
One special property of flow in the cardiovascular system is that blood viscosity is variable. In the space below, briefly explain TWO factors that contribute to the variable viscosity of blood.
Factor 2
(2) Blood viscosity depends on blood flow rate: Blood viscosity increases as flow rate decreases (e.g. due to clotting). May also say blood is a non-Newtownian fluid (Newtonian fluids have constant velocity at all flow rates, like water).
One special property of flow in the cardiovascular system is that blood viscosity is variable. In the space below, briefly explain TWO factors that contribute to the variable viscosity of blood.
Factor 3
(3) Blood viscosity depends on RBC shape: Healthy RBCs are flexible. Reduced RBC flexibility in disease (e.g. sickle cell anemia) makes blood more viscous.
- Which TWO of the following are synonyms for spongy bone?CIRCLE TWO OPTIONS
(2 marks)
CANCEROUS BONE
COMPACT BONE
CORTICAL BONE
EPIPHYSEAL BONE
WOVEN BONE
TRABECULAR BONE
SECONDARY BONE
CANCELLOUS BONE
TRABECULAR BONE*
CANCELLOUS BONE*
- Classify each of the following statements as TRUE or FALSE (circle ONE option) (3 marks)
Statement
- Circle one*
- At resting membrane potential, K+ is at electrochemical equilibrium, but Na+ is not.
TRUE
FALSE
- Only excitable cells have a resting membrane potential.
TRUE
FALSE
TRUE
FALSE
- Current is defined as the movement of charge, and only occurs in the presence of a conductor.
TRUE
FALSE
- Volts (V) are the units of potential difference.
TRUE
FALSE
- Membrane permeability is one of the two main determinants of membrane potential.
TRUE
FALSE
- Classify each of the following statements as TRUE or FALSE (circle ONE option) (3 marks)
Statement
- Circle one*
- At resting membrane potential, K+ is at electrochemical equilibrium, but Na+ is not.
FALSE**
- Only excitable cells have a resting membrane potential.
FALSE**
TRUE**
- Current is defined as the movement of charge, and only occurs in the presence of a conductor.
TRUE **
- Volts (V) are the units of potential difference.
TRUE**
- Membrane permeability is one of the two main determinants of membrane potential.
TRUE**
List TWO major features of the nervous system of VERTEBRATES (bilaterally symmetrical, e.g. humans)
1
Cnidaria: diffuse nerve net; no clear afferent/efferent division, no central nervous system/ganglia
List TWO major features of the nervous system of VERTEBRATES (bilaterally symmetrical, e.g. humans)
2
Veterbrates: Presence of ganglia; strong cephalisation (highly developed integration centre (aka brain) at anterior end); part of nervous system encased with bone or cartilage; nerve (spinal) cord runs along dorsal surface; nerve cord is hollow (contains cerebrospinal fluid)
- The diagram below shows the patellar (myotatic) reflex, with various components labelled A to F.The components are also listed below the diagram.Match each component on the list to one of labels A to E.Circle each match in the table below the diagram.(3 marks)
Circle ONE correct option for each
Excitatory synapse
A
B
C
D
E
F
Inhibitory synapse
A
B
C
D
E
F
Sensory (afferent) nerve
A
B
C
D
E
F
Motor (efferent) nerve
A
B
C
D
E
F
Muscle spindle
A
B
C
D
E
F
Dorsal root ganglion
A
B
C
D
E
F
Excitatory synapse
D**
Inhibitory synapse
E**
Sensory (afferent) nerve
B**
Motor (efferent) nerve
F**
Muscle spindle
A**
Dorsal root ganglion
C**
Define and give an example presented in the lectures by Jim Cummins (on Adaptation and Size) of the following concepts
a. Differential reproductive fitness for a given biological trait.
Definition: Individuals with an advantageous heritable trait have more offspring than do individuals without the trait
Example: Any example of evolutionary success, in fact any existing species is by definition “successful” (some might mention religion and memes: 0.5 marks as these don’t have “traits” in a biological sense).
Genotype
Define
Example
Definition: the set of genes carried by an organism
Example: any animal or plant genome (e.g. ~22,000 human genes). Examples in the lectures were of (1) bighorn sheep with the genes for large rapidly growing horns selected against by human trophy hunting and (2) hunting of Bison by Paleoindians in N. America led to changes in body conformation, reproduction and behavior (e.g. intensive herding).
Allopatric speciation
Define
Example
Definition: Speciation caused by physical separation of two or more populations leading to reproductive isolation by genetic and phenotypic drift (e.g., by a mountain range or body of water).
Example: Galapagos island finches vs. ancestral types in S. America
Bergmann’s rule
Definition
Example
Definition: Homoeothermic animals from higher altitudes and latitudes, or bred at lower temperatures, tend to be larger.
Example given: Human populations in high latitudes (e.g., Inuit)
Evolutionary dwarfism
Define
Example
Definition: Permanent reduction in body size in islands or restricted habitats.
Examples given: pygmy elephants on Cyprus; “Hobbit” hominids on Flores; Human pygmies in jungle environments; Wrangel Island mammoth reduced by 65% over the 5000 years after the mainland connection was lost.
