Lecture 6 Flashcards
(135 cards)
1
Q
how have animal structures evolved? what is an example?
A
-as a result of functional outcomes
-ex: beavers flat and wide tail (used for locomotion, communication, body temp regulation)
2
Q
what is anatomy?
A
-the biological form of an animal
-features that have evolved to enable survival in an animal’s environment
3
Q
what is physiology?
A
-the biological functions an organism performs
4
Q
what does the comparative study of animals reveal?
A
-that form and function are closely correlated
5
Q
what is the basic principle?
A
-there is adaptation through natural selection
-variation meets environment
6
Q
what does the size and shape of an animals forms affect?
A
-the way an animal interacts with its environment
-how it exchanges energy + materials with its surroundings (larger SA = higher exchange)
7
Q
what does the genome determine?
A
-an animals body plan
8
Q
what ability depends on an animals shape, size, and environment?
A
-ability to perform certain actions
9
Q
what does evolutionary convergence reflect?
A
-different species adaptations to a similar environmental challenge
10
Q
what happens when body dimensions increase?
A
-when body dimensions increase, stronger skeletons are needed to provide support
-muscles also must increase for locomotion purposes
11
Q
what is an example of how physical laws impose constraints on animal size + shape
A
-waters dense property will limit the shape of fast swimmers
-tapered on both ends and body will be sleek to overcome drag during swimming
12
Q
how does exchange occur within an animals cells?
A
-substances that have dissolved in an aqueous medium will diffuse and be transported across the membrane
13
Q
what substances are typically exchanged?
A
-nutrients
-wastes
-gases
14
Q
what correlates with the rate of exchange?
A
-membrane surface area
15
Q
what correlates with the amount of material exchanged?
A
-cell volume
16
Q
what allows multicellular organization to work?
A
-every cell having access to a suitable aqueous environment (inside + outside the body)
-body plans must meet this requirement
17
Q
what are ideal body plans for multicellular organization?
A
-sac body plan
-body walls are only 2 cells thick to facilitate diffusion
-flat body plan
-most cells are exposed to intestinal fluid
18
Q
how do highly complex organisms with high cell numbers increase their outer SA to volume ratio?
A
-branching + foldings
19
Q
in vertebrates, what is between cells? what does this allow for?
A
-interstitial fluid
-allows for movement of material in and out of cells
-exchange with the circulatory fluid
20
Q
what is biggest challenge for physiological systems?
A
-being able to survive in a variable environment
21
Q
what helps animals survive in a variable environment?
A
-a complex body plan
-helps to keep the internal environment of the animal stable
22
Q
for what type of animals specifically does a complex body plan help? why?
A
-land animals
-environments typically are more variable
23
Q
what are most animals composed of?
A
-specialized cells organized into groups called tissues that deliver different functions
24
Q
what do different tissue types create? what together will these create?
A
-create organs
-organs will together create organ systems
25
what do organ systems entail?
-higher level of organization and coordination
26
what differs between different tissue types?
-their structures
-structures are suited to their desired function
27
what two structures/organs are lined with similar tissue types?
-lungs
-blood vessels
28
what are the four main tissue catergories?
-epithelial
-connective
-muscle
-nervous
29
what is the purpose of epithelial tissue?
-covers the outside of the body and lines organs and cavities within the body
-functions as a barrier
30
how are cells jointed within epithelial tissue?
-closely
31
what is the purpose of connective tissue?
-mainly binds and supports other tissues
32
what does connective tissue contain?
-sparsely packed cells scattered throughout an extracellular matrix
-fibroblasts
-macrophages
33
what do fibroblasts secrete?
-fibre proteins
34
what do macrophages do?
-engulf foreign particles and cell debris through phagocytosis
35
what does the extracellular matrix contain?
-fibres in a liquid jelly like or solid foundation/base
36
what are the types of muscle tissue?
-cardiac muscle
-skeletal muscle/striated muscle
-smooth muscle
37
what is the purpose of cardiac muscle?
-contraction of the heart
38
what is the purpose of skeletal muscle?
-attached to bones and is responsible for voluntary movement
39
what is the purpose of smooth muscle?
-lines internal organs and is responsible for involuntary movement
40
what is the purpose of nervous tissue?
-senses stimuli and transmits signals throughout the body
41
what does nervous tissue contain?
-neurons/nerve cells
-glial cells/glia
42
what is the function of neurons/nerve cells?
-transmit impulses
43
what is the function of glial cells/glia
-nourish, insulate, and replenish neurons
44
what systems do control and coordination within the body depend on?
-endocrine system
-nervous system
45
what does the endocrine system do?
-transmits chemical signals called hormones to receptive/target cells throughout the body via the blood
46
how many regions of the body can a hormone affect?
-one or more
47
what is an example of a fast acting hormone?
-epinephrine (adrenaline)
48
what is an example of a slow acting hormone?
-thyroid stimulating hormone
49
can slow acting hormones have long lasting effects?
-YES
50
what does the nervous system do?
-transmits information between specific locations
51
what does the information conveyed within the nervous system depend on?
-the signals pathway
52
what does the information conveyed within the nervous system not depend on?
-the type of signal
53
is nerve signal (electrochemical) transmission fast or slow?
-very fast
54
what types of cells can nerve impulses be received by?
-neurons
-muscle cells
-endocrine cells
55
how do animals manage their internal environment?
-by regulating or conforming to the external environment?
56
how does a regulator deal with external environment changes?
-use internal control mechanisms to keep internal conditions stable despite environmental changes
57
how does a conformer deal with external environment changes?
-allows its internal condition to vary relatively equally with the environmental changes
-may also seek other environments
58
is it more energetically expensive to be a regulator or a conformer?
-regulator
59
is it possible for animals to be both a regulator and a conformer depending on the nature of the conditon?
-YES
-no animal is truly one or the other, they just tend to be more of one than the other
60
what is an example of an animal that is a regulator for one condition and a conformer for another condition?
-largemouth bass
-thermoconformer
-ionregulator
61
what is homeostatis?
-maintenance of internal balance (keeping a constant internal environment)
62
in humans what conditions are maintained at a constant level by homeostatsis?
-body temp
-blood pH
-glucose []
63
what serves as the stimulus for homeostatsis?
-flucutuations above or below the internal set point
64
what detects stimuli? what does this trigger?
-sensor or receptor in the body
-triggers a response to bring the condition back to the set point
65
how does negative feedback act? what stops the system?
-acts to reverse/return a condition to its normal range/set point
-a buildup of the end product will shut the system off
66
how do most homeostatic control systems function?
-by negative feedback
67
how does positive feedback act? what is an example of where positive feedback acts?
-acts to drive certain processes (not usually contributing to homeostasis)
-escalate a trend
-ex: childbirth
68
what are some important aspects of set points and normal ranges?
-may change with age
-can show cyclic patterns (circadian rhythm)
69
what is often confused with adaptation?
-acclimation
-acclimization
70
what is acclimation?
-remodeling in response to a single environmental factor
-simple
71
what is acclimization?
-the process of the adjustment of homeostasis to complex changes in the external environment
-complex
72
what is thermoregulation?
-the process by which animals maintain an internal temperature within a normal range
73
what are many processes dependant on?
-temperature
-higher temp may increase efficiency or vice versa
74
what are endothermic animals? what are examples?
-animals that generate heat by metabolism (internal body processes)
-can withstand large fluctuations in their external environment
-ex: birds + mammals
75
what are ectothermic animals? what are examples?
-animals that gain heat from external sources
-may produce some heat in metabolism but not an influential amount
-ex: most invertebrates, fishes, amphibians, and reptiles
76
generally which type of animals will need to consume less food? why?
-ectotherms
-don't need to fuel metabolic process as much as endotherms
-endothermy is more energetically expensive (need a higher consumption)
77
what is the key difference between endotherms and ectotherms?
-endotherms are active at a greater range of external temperatures
-ectotherms can tolerate greater variation in internal temperatures
78
how is the body temperature of a pokilotherm?
-varies with its environment
79
how is the body temperature of a homeotherm?
-relatively constant
-not perfectly correlated with endothermy and ectothermy
80
how is the body temperature of a heterotherm?
-maintains different temperatures within different regions of its body
-ex: shark
81
how do organisms exchange heat?
-through 4 processes
-conduction
-convection
-radiation
-evaporation
82
what does heat regulation in mammals typically involve?
-the integumentary system (skin, hair, nails)
83
what is radiation?
-emission of electromagnetic waves (sunlight)
84
what is conduction?
-direct transfer of heat through contact
85
what is convection?
-transfer of heat through movement of air or liquid
86
what is evaporation?
-removal of heat by evaporation
87
what are the 5 adaptations that help animals thermoregulate?
-insulation
-circulatory adaptations
-cooling by evaporative heat loss
-behavioural responses
-adjusting metabolic heat production
88
what are examples of things that insulate animals? what do they do exactly?
-skin, feathers, fur, and blubber
-reduce heat flow between an animal and its environment
89
what are animals changing with circulatory adaptations?
-how much blood flow is near the bodies surface
90
what are the 3 methods of circulatory adaptations?
-vasodilation
-vasoconstriction
-countercurrent exchange
91
what is vasodilation?
-blood flow near the surface increases, facilitating heat loss to the environment (endotherm common)
-superficial blood vessels widen
92
what is vasoconstriction?
-blood flow near the surface decreases, lowering the amount of heat loss to the environment
-superficial blood vessels shrink
93
what is countercurrent exchange?
-heat is transferred between fluids flowing in opposite directions (veins + arteries)
-artery temp is warmer than vein temp
-important mechanism for reducing heat loss
-can be temporarily shut down
94
what allows for an animal to perform countercurrent exchange? what types of animals perform this?
-the arrangement of their blood vessels
-ex: marine mammals and birds
95
what is evaporative cooling? what increases the cooling affect?
-heat loss through the evaporation of water in sweat
-sweating cools an animal down
-panting can increase this effect
96
what are behavioural responses to control body temp?
-seeking areas of ideal temperature
-terrestrial invertebrates have postures that minimize or maximize the absorption of solar heat (sun)
97
how is metabolic heat production increased typically?
-muscle activity (moving or shivering)
98
what do some mammals poses that help produce heat?
-brown adipose tissue (specialized to produce heat)
-produce heat by cells through proteins called thermogenin
99
how do the thermogenin proteins produce heat?
-cause mitochondria to produce heat rather than ATP
100
what is the process of heat production called?
-thermogenesis
101
what region of the brain controls thermoregulation?
-hypothalamus
-triggers heat loss or heat generating mechanisms
-sensor/receptor
102
what type of environment do physiological systems operate in? what must be maintained here?
-fluid environment
-water and solute concentrations must be maintained within fairly narrow limits (maintaining osmolarity)
103
what is osmoregulation?
-regulates solute concentrations and balances the loss and gain of water
104
what are the common solutes that must be maintained within the body?
-sodium
-calcium
105
what adaptations do freshwater animals have to help with osmoregulation?
-adaptations that reduce water uptake and conserve solutes
106
what kind of environments do desert and marine animals live in? how do they adapt?
-desiccating environments that can deplete body water
-conserve water in fish
-eliminate excess salt in marine birds + fish
107
what does excretion get rid of?
-nitrogenous metabolites
-waste products
108
what is osmoregulation largely based on?
-controlled movement of solutes between internal fluids and the external environment
109
what do cells require in terms of osmoregulation?
-a balance between osmotic gain and the loss of water in order to regulate chemical composition of body fluids
110
what is osmolarity? what does it determine? what are its units?
-the solute concentration of a solution
-determines the movement of water across a selectively permeable membrane
-units are osmoles of solute per litre of solution (Osm/L)
111
what does it mean for 2 solutions to be isosmotic?
-the movement of water is equal in both directions
-no net movement of water
112
what is a hypoosmotic solution?
-more dilute solution
113
what is a hyperosmotic solution?
-less dilute solution
114
what will happen if 2 solutions differ in osmolarity?
-the net flow of water will be from the hypoosmotic solution to the hyperosmotic solution
115
what are osmoconformers? what animals are they?
-isosmotic with their surroundings and do not regulate their osmolarity
-ex: only some marine animals (most marine invertebrates)
116
what are osmoregulators? what animals are they?
-expend energy to control water uptake in a hypoosmotic environment and water loss in a hyperosmotic environment
-minimizes the change in internal osmolarity
-ex: freshwater and some marine animals (marine vertebrates and some invertebrates)
117
what determines solute concentrations?
-the activity of protein transporters that move ions and solutes in and out of the cell
118
what type of animals differ in their ability to tolerate changes in external environments?
-aquatic animals
119
what does it mean for an animal to be stenohaline?
-cannot tolerate substantial changes in external osmolarity
-makes up most animals
120
what does it mean for an animal to be euryhaline?
-can survive large fluctuations in external osmolarity
121
does an animals osmotic strategy relate to their osmotic tolerance? what is an example?
-they do not relate
-ex: sockeye salmon is a euryhaline osmoregulator
122
how do terrestrial animals regulate water movement?
-through diet and excretion
123
what is known of the physiological mechanisms for water and ion balance in terms of their evolutionary history?
-they have been evolutionarily conserved
-meaning they are present in a majority of species (origin to present)
124
how do marine bony fishes perform osmoregulation?
-hypoosmotic to seawater (lose water by osmosis, gain salt by diffusion and from food)
-balance water loss by drinking seawater and excreting salts (through kidney and gills)
125
how do the gills of marine bony fishes excrete salts?
-actively transport Cl- out and passively allow Na+ to follow
126
how does the kidney of marine bony fishes excrete salts?
-excess calcium, magnesium, and sulfate excreted in small amounts of water
127
how do freshwater animals perform osmoregulation?
-take in water constantly by osmosis (hypoosmotic environment)
-lose salt by diffusion
-maintain water balance by excreting large amounts of dilute urine
-salt loss is replaced by food intake + gill uptake
128
what is a diadromous fish? what are some examples?
-live part in salt and part in freshwater
-ex: salmon + eels
129
what is required for a fish to be diadromous? what is this process called?
-reorganization of osmoregulatory systems
-smoltification (complex series of changes)
130
what is smoltification and when does it occur?
-complex series of physiological changes
-prepares fish to enter seawater after the final step of acclimization
131
how are desert animals able to save so much water?
-simple anatomical features (body coverings)
-behaviours (nocturnal lifestyle)
132
how are land animals able to lose and gain water?
-lose water through urine, feces, skin, etc
-gain water through drinking, eating moist foods, and metabolic water
133
what is transport epithelia?
-specialized epithelial cells that regulate solute movement
-essential component of osmotic regulation and metabolic waste disposal
134
how is transport epithelia arranged?
-complex tubular networks (increase SA)
135
what is an example of transport epithelia?
-the salt glands of marine birds
-remove excess sodium chloride from the blood
