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Unit 3: Animal Biology Flashcards

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Biology 101 flashcards
1
Q

What are the 5 core concepts of biology as they relate to animal development and physiology?

A
  1. Structure and function
  2. Evolution
  3. Systems
  4. Information flow
  5. Transformations of energy and matter
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2
Q

What factors make an animal (5 key points discussed)

A
  • Multicellular
  • heterotrophic: must obtain nutrients from other organisms
  • lack cell walls
  • capable of movement at one point in life stage
  • Possess regulatory hox genes (all have same genes)
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3
Q

Is a sponge considered an animal? Why?

A
  • yes since it agrees with all requirements for an animal
  • can move at the larval stage
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4
Q

What functions do animals need?

A
  • reproductive/development
  • obtain matter and energy / transport it
  • gas exchange (breathing)
  • protection from external environment
  • maintain water/solute concentration
  • support/ movement
  • coordination of body functions
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5
Q

How does structure relate to function?

A

Structure can enable or constrain function

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6
Q

How does structure enable function?

A
  • a structures physical and chemical characteristics influence its interactions with other structures, and therefore its function
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7
Q

How does structure constrain function?

A
  • functional tradeoffs
  • specialization for one function may limit a structure’s ability to perform another function
  • it is impossible to optimize for all parameters
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8
Q

What are the two forms of tradeoff?

A
  • functional tradeoffs
  • resource tradeoffs
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9
Q

What is evolution?

A
  • through natural selection organisms become adapted to their environment
  • structures make sense in the context of the animal’s environment
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10
Q

What is the hierarchal organization of structures?

A

molecules, organelles, cells, tissues, organs, organ systems, organisms

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11
Q

How do biological structures interact? How might one change in one component of a network impact other components?

A
  • interact to form complex systems
  • a change can affect other components
    eg: issues with cell can cause deflation of cartilage = mobility issues
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12
Q

What are emergent properties?

A
  • each level of organization has properties exhibited by lower levels
  • these are properties that exist due to many different components working together
    eg: Structure –> emergent property: cell –> life
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13
Q

Provide an example of an emergent property

A
  • cardiac muscle contracts
  • cardiac muscle + tissue = heart (organ) = coordinated pumps
  • heart + blood + vessels = circulatory system –> delivers O2

= rewrites all different components to deliver O2 throughout the body

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14
Q

What does exchange of materials look like for a structurally simple animal?

A
  • some animals structurally simple enough that all cells are in direct contact with external environment
  • don’t need systems for exchange - does it alone
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15
Q

What does exchange of materials look like in more complicated bodies ?

A

complicated bodies require organ systems that
- can exchange material with external environment
- can transport material around body

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16
Q

What are the systems which allow for exchanging of materials in complex systems? For transport?

A
  • digestive system, excretory, reparatory, integumentary
  • circulatory system transports material throughout
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17
Q

How do animals respond to changes in internal and external environments?

A
  • animals have systems that perceive and respond to changes in internal and external environments
  • all perception and response requires information flow
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18
Q

What is communication in terms of information flow in animals?

A
  • perception and response requires information flow
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19
Q

How does communication occur?
What are these systems called?

A

chemical and/or electrical signalling between cells coordinates responses at cellular, tissue, organ, and system levels
- called endocrine and nervous systems that control response to stimuli/coordinate body activities

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20
Q

What is homeostasis?
- Why are stable environments important?

A
  • the maintenance of a relatively stable internal environment (systems help maintain this)
  • cells have conditions under which they function optimally, enzymes/membranes sensitive to changes in surroundings
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21
Q

Which feedback system does homeostasis rely on?

A
  • negative feedback: control mechanism in which response opposes original stimulus
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22
Q

What is transformational energy?

A
  • regulate changes in asset points and normal ranges of physiological parameters essential to normal body functions
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23
Q

What are some examples of regulated changes?

A
  • stages of life, cyclic, response to environmental change
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24
Q

Where do animals get their energy?

A

Food:
- chemical energy = sugars, fats, proteins, energy stored in bonds
- molecular building blocks (eg: amino acids)

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25
Q

What energy ‘currency unit’ do animals use in their body?

A
  • stood chemical energy is converted to ATP
  • also stores energy within bonds
  • needed to carry out cellular work necessary for physiological activities
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26
Q

how does natural selection favour efficient use of resources?

A
  • organisms have limited energy and material resources
  • requires efficient allocation across competing functional demands
  • resource trade-offs
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27
Q

What are resource tradeoffs?

A

natural sleeting favours efficient use of resources, requires specific allocation of energy. May need to give one thing up in order to do another
eg: wound healing vs. egg protection

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28
Q

What are the 3 embryonic stages ?

A
  • cleavage
  • blastula
  • gastrulation
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29
Q

What is the foundation of diverse cell types and behaviours seen in development? In other words, how can cells which possess the same genomes look and behave differently?

A

Differential gene expression

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30
Q

Why are model organisms broadly representative?

A
  • developmental genes and mechanisms are very similar across animal species
  • therefore studying development in model organisms provides knowledge about development in general
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31
Q

What is the relationship between genes of drosophila and humans?

A
  • have similar genes that perform similar functions
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32
Q

What is fertilization?

A
  • haploid gametes (n) join to form diploid zygote (2n)
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33
Q

Describe the steps of fertilization in sea urchins

A

1) sperm and egg are haploid gametes
2) contact with jelly cat triggers acrosomal reaction
3)surface repotting on acrosomal process binds to receptors on egg cells membranes
4) plasma membranes fuse triggering fast block to polyspermy
5) sperm nucleus enters and cortical reaction causes slow block to polyspermy
6) fusion of sperm and egg nuclei form the diploid nucleus of zygote

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34
Q

What is an acrosomal reaction?

A
  • surface proteins on acrosomal process binds to receptors on egg cell membrane - triggers fast block
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35
Q

What is cleavage?

A
  • the process by which zygote becomes multicellular
  • rapid cell division with little growth of cells
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36
Q

What stages of mitosis does cleavage skip? Why?

A
  • skips G1 and G2 phase for rapid division with little growth
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37
Q

What is developed from cleavage?

A
  • results in many smaller cells called blastomeres (become blastula)
  • cells get smaller with each round of division
  • no growth of cells between divisions
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38
Q

What is the blastula?

A
  • developed from blastomeres
  • hollow ball of cells with a fluid filled cavity called the blastocoel
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39
Q

What is differential gene expression?

A
  • cells express different genes depending on their location and stage development
  • expressing different genes leads to the production of different proteins which determine structure/behaviour
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40
Q

What do the different proteins formed from differential gene expression do?

A
  • determine structure and behaviour of cell at any given time (allows for different traits despite having same genomes)
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41
Q

What are the two mechanisms which allow genes to know what genes to express at a given time?

A
  • 1) cytoplasmic determinants - signal comes form within the cell
    2) inductive signals - signal comes from outside the cell
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42
Q

What are cytoplasmic determinants ?

A
  • molecules within cytoplasms regulates gene expression
  • can be differentially distributed to daughter cells resulting in differences in gene expression
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43
Q

What mechanism is responsible for an asymmetric cell division?

A
  • cytoplasmic determinants
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44
Q

What are inductive signals?

A
  • signal molecules a cell is exposed to depend on its location within the embryo and the stage of development
  • as cell develops different conditions allow it to express different traits
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45
Q

What is morphogenesis?

A
  • rearrangement of cells r sheets of cells in the embryos
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46
Q

What is gastrulation?

A
  • stage when 3 germ layers are established, and basic body plan is set up
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47
Q

What is organogenesis? Provide and example

A
  • the formation of the organs
  • neurolation ; formation of the nervous system
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48
Q

What are the 3 layers formed from castellation called?

A

ectoderm, mesoderm, endoderm

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49
Q

What are the steps of frog gastrulation?

A
  1. Cells in vegetal hemisphere push inward
  2. outer cells (future endoderm and mesoderm) roll inward
  3. Blastocoel collapses and new cavity - archenteron - is formed
  4. cells at animal pole (future ectoderm) spread over the outer surface
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50
Q

What forms the endoderm and mesoderm?

A
  • the outer cells of blastula which roll inward
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51
Q

What is the archenteron?

A
  • when the blastocoel collapses the new cavity archenteron is formed
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52
Q

How is morphogenesis achieved?

A
  • achieved through changes in cell position, shape, and survival
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53
Q

What is convergent expression?

A
  • example of cells changing position
  • produces a longer, narrower structure
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54
Q

Know the formation of the neural tube (review diagram)
- how is the neural tube formed?

A
  • ectodermal cells change shape during neural tube formation
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55
Q

what is programmed cell death’s role?

A
  • also shapes embryos
  • fluorescing cells are undergoing apoptosis eg: removal of webbing between digits
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56
Q

What is apoptosis?

A

the death of cells which occurs as a normal and controlled part of an organism’s growth or development.

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57
Q

What animals are best to model development?
list one reason why either one of these is effective

A

Frogs and urchins
- urchins have transparent, external eggs

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58
Q

What are the parts of the blastula?

A
  • formed from blastomeres, doesn’t change size from og. zygote
  • has animal pole and vegetal pole
  • animal pole is the ‘top’ where the stem enters, has smaller cells than the vegetal side
  • also contains blastocoel- a fluid filled cavity
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59
Q

What are the 3 kinds of morphogenesis?

A

1) Gastrulation
2) organogenesis
3) programmed cell death

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60
Q

True or False: Endodermal cells express different genes than ectodermal cells

A

True! Despite having the same genes, they express them differently depending on different determinants (cytoplasmic determinants and inductive signals)

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61
Q

What are the roles of the nervous and endocrine system?

A
  • major systems that control responses to stimuli and coordinate body functions and maintain homeostasis
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62
Q

What are the characteristics of the endocrine system?

A
  • hormonal signal type
  • blood transmission
  • speed = fast/slow
  • specificity is achieved by hormone/receptor interaction (target cells have receptor proteins)
  • single travels everywhere in body
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63
Q

What are the characteristics of the nervous systems?

A
  • electrical impulse and chemical neurotransmitter signal
  • neuron transmission
  • very fast
  • short duration
  • specificity is achieved by close connection of neuron’s and target cells (eg: neutrons, muscle, endocrine cells)
  • travels to specific location
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64
Q

What is the endocrine system for?

A
  • specialized for coordinating gradual changes that effect the entire body
    eg: growth and development, reproduction, metabolic progresses, digestion
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65
Q

What is the nervous system?

A
  • specialized for directing immediate and rapid response to the environment
    eg: rapid locomotion and behaviour
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66
Q

What are nervous systems composed of ?

A
  • neurons and glia
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67
Q

What are neutrons?

A

cells responsible for generating and transmitting electrochemical impulses of the nervous systems

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68
Q

What are glia?

A
  • cells that maintain homeostasis
  • form myelin, nourish, and provide support and protection for neurone in the central and peripheral nervous systems
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69
Q

What are the main parts of the nervous system ?

A
  • dendrites, axon, nucleus, synapse : neurotransmitter, synaptic terminal
  • presynaptic cell, post synaptic cell
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70
Q

What are the steps of communication through the nervous system?

A

1) electrical impulses are triggered at dendrites
2) with sufficient stimulus to cell body, a new electrical impulse is generated and send down axon
3) neurotransmitter is released and crosses the synapse to bind to receptors on the post synaptic cell

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71
Q

What forms the central nervous system?

A
  • brain and spinal cord
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72
Q

What dorms the peripheral nervous system?

A
  • cranial ner es, ganglia, spinal nerves
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73
Q

What are the 3 stages of information processing ?

A

1) sensory input
2) integration (central nervous system)
3) motor output (peripheral nervous system) –> effector

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74
Q

What are the 3 neurons?

A
  • sensory nurons, interneuron, motoneuron
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75
Q

What do endocrine cells do?

A
  • endocrine cells secrete hormones into the bloodstream, affecting target cells to regulate physiology and behaviour
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76
Q

What parts of the body produce hormones?
which are the two major endocrine glands?

A
  • organs produce hormones
  • major endocrine glands: hypothalamus, pituitary gland
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77
Q

What is the hypothalamus?

A
  • a brain region that acts as the “master regulator” of the endocrine system primarily through the pituitary gland
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78
Q

What are the parts of the hypothalamus?

A

hypothalamus, posterior pituitary, anterior pituitary

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79
Q

Wha is the posterior pituitary?

A
  • made up of axons of neurosecretory cells of the hypothalamus
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80
Q

What are neurosecretory cells?

A
  • neurosecretory cell is a neuron that produces a hormone and secretes it into the bloodstream
  • functional overlap between nervous and endocrine system
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81
Q

What system is an overlap between nervous and endocrine system?

A
  • the posterior pituitary
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82
Q

What is the anterior pituitary?

A
  • made up of endocrine cells that respond to hormones from the hypothalamus by secreting their own hormones
  • hypothalamic hormones arrive via portal vessels
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83
Q

How do hypothalamic hormones arrive?

A

via portal vessels

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84
Q

What regulates other endocrine glands?

A
  • hormones from the posterior and anterior pituitary glands
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85
Q

What is the hierarchal organization of hormone secretion?

A

hypothalamus – > posterior/pituitary glands –> other endocrine glands eg: thyroid, adrenals, testes, ovules

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86
Q

What systems do the fight or flight systems require?

A
  • requires nervous and endocrine systems
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87
Q

What controls the connection between nervous and endocrine systems?

A
  • the hypothalamus
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88
Q

How does the hypothalamus affect fight or flight?

A
  • hypothalamus affects endocrine system without pituitary - via spine and then adrenal glands
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89
Q

What are some effects of hormones?

A
  • increased heart rate
  • breathing rate
    -metabolic rate
  • blood glucose
  • change in blood flow pathogen
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90
Q

What does it mean for hormones to differ in structure and solubility?

A
  • a single hormone can produce different effects in different cells
  • response of a target cell to a hormone depend on - signalling pathways within target cell
  • the type of receptor on target cells
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91
Q

What is the difference between water soluble and insoluble hormones?

A
  • water soluble passes through membrane (from secretory cell)
  • water insoluble requires proteins/receptors
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92
Q

How do endocrine systems maintain homeostasis?

A
  • endocrine systems often use antagonistic hormones to maintain homeostasis
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93
Q

What are antagonistic hormones?

A
  • Pairs of hormones whose actions oppose each other
  • maintain a physiological parameter within an acceptable range
  • ex: insulin and glucagon regulate blood glucose concentration
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94
Q

what hormones does the adrenal gland secrete?

A
  • epinephrine and norepinephrine
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95
Q

Describe the negative feedback loop of blood glucose

A

too low = alpha cells of pancreas releases glucagon = live breaks down glycogen, release glucose = blood glucose increases = homeostasis!

Too high = beta cells in pancreas releases insulin = liver removes glucose from blood, stores it as glycogen = blood glucose decreases = homeostasis

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96
Q

What is bioenergetics?

A

The overall flow and transformation of energy within an organism

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97
Q

What determines how much energy an animal needs?

A
  • metabolic rate
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98
Q

What is the metabolic rate?

A
  • the amount of energy used per unit time
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99
Q

What is the basal metabolic rate?

A

BMR is the metabolic rate of a non-grown endotherm (Warm blooded animal) that is at rest, with an empty digestive tract, and not experiencing stress
ie: the minimum amount of energy to maintain basic functions

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100
Q

What determines metabolic rate?

A
  • many factors: sex, age, size, temperature, nutrition
  • primaries: activity level, body mass,
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101
Q

Does a smaller or larger animal have a greater metabolic rate?

A
  • smaller animals have higher metabolic rate (more activity, larger animals use energy more efficiently)
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102
Q

What must an animal’s diet do?

A
  • must supply energy, organic molecules, and essential nutrients
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103
Q

What is chemical energy in food used for?

A
  • used in cellular respiration to produce ATP or is stored
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104
Q

Why are organic molecules needed?

A
  • needed for biosynthesis of nucleic acids, carbohydrates, proteins, lipids
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105
Q

What are essential nutrients? from an animals diet?

A
  • essential amnio acids, fatty acids, vitamins, and minerals
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106
Q

What are the 4 stages of food processing?

A
  1. Ingestion : mechanical ingestion
  2. Digestion: chemical digestion = enzymatic hydrolysis
  3. Absorption: nutrient molecules enter body cells
  4. Elimination: undigested material
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107
Q

Why are the structures associated with ingestion the most diverse?

A
  • various diets
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108
Q

what are the 4 main feeding mechanisms?

A
  • suspension/filter feeders
  • substrate feeders
  • fluid feeders
    -bulk feeders
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109
Q

What are the components of the digestive system? What is it for?

A
  • alimentary canal + accessory organs
  • specialized for sequential stages of food processing
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110
Q

What pushes food along?

A

Peristalsis

111
Q

What separates compartments in the digestive system?

A
  • sphincters between compartments
112
Q

What is the oral cavity? What foes it contain?

A
  • oral cavity is the first site of chemical and mechanical digestion
  • contains salivary glands which produce saliva
113
Q

What does saliva contain?

A
  • mucus: protects lining of mouth and lubricates food
  • buffers: helps prevent tooth decay by neutralizing acid
  • antimicrobial agents: lysozome
  • Salivary amylase: enzymatic breakdown of carbs
114
Q

How does food move from the mouth to the stomach?

A
  • swallowing reflex and esophageal peristalsis
115
Q

Describe the states of the epiglottis and esopgogeal sphincter during swallowing

A

initially up and contracted until swallowing when it opens and relaxed

116
Q

Where does mechanical digestion occur?

A

in the mouth and continues in the stomach (stomach contracts)

117
Q

What is the epithelium?

A
  • in the stomach, secretes gastric juice
  • food mixes with gastric juice to become chyme
118
Q

What is found on the interior surface of the stomach?

A
  • gastric pits on interior surface of stomach, connected to gastric glands
119
Q

What are the components of the gastric glands?

A

3 specialized cells
- mucous cells, chief cells, parietal cells

  • parietal cells release hydrogen and chlorine ions
  • chief cells release pepsinogen which when it meets HCl is turned into active pepsin (which encourages production of pepsinogen = positive feedback)
120
Q

What does the liver produce?

A

Liver proceeders bile, gallbladder stores bile, bile released into small intestine to emulsify fats

121
Q

Why does our alimentary canal not digest itself?

A
  • mucus provides protection for cells lining alimentary canal
  • HCL and digestive enzymes maintain inactive forms until released to alimentary canal lumen (stomach lining)
  • rapid turnover of cells lining alimentary canal
122
Q

What is the small intestine good for?

A
  • well suited for digestion and absorption
123
Q

What is responsible for nutrient absorption in the small intestine?

A
  • veins carry blood to liver
  • large circular folds, villi, and microvilli allow for greater nutrient absorption (larger SA)
124
Q

What is the livers role?

A
  • regulates distribution of nutrients to rest of body
  • functions in detoxification
  • acts like a “guard post” between what you ingest and the rest of your body
125
Q

Why is the structure of the small intestine so well suited for absorption?

A
  • large surface area, many blood vessels connecting with small intestine carry materials to the liver
126
Q

Describe the large intestine

A
  • composed of the Colin, cecum, and rectum
127
Q

What is the tole of the cecum? Why might it be smaller in carnivores?

A
  • in the large intestine, functions in fermenting ingested plant material (using symbiotic bacteria)
  • smaller in carnivores due to its role in plant fermentation, so eats less plants = smaller and intestines are therefore shorter
128
Q

What is the colon’s function?

A

Functions in water reabsorption and formation/elimination of the feces
- majority of water is reabsorbed in the small itenstine, but colon does to
- feces consists on undigested materials and bacteria

129
Q

What are hormones function in the body? What triggers their release in the body, and what do they trigger?

A
  • regulate digestion and energy storage
  • triggered by the presence of food, which then trigger the secretion of gastric juices and digestive enzymes
130
Q

What is the role of the hormones insulin and glucagon?

A
  • insulin causes excess energy to be stores as glycogen in liver and muscle, then as fat in adipose cells
  • glucagon secreted during energy deficit causes breakdown of liver glycogen then muscle glycogen and fat
  • remember feedback loop
131
Q

What hormones are released when we’re hungry and full?

A

insulin and peptide YY are secreted in response to a meal and gherkin is secreted when the stomach is empty

132
Q

How do hormones regulate appetite?

A
  • a satiety centre in brain generates the nerve impulses that makes us feel hungry and full
  • leptin is produced by adipose and regulates long term appetite
133
Q

Why do animals eat?

A
  • require external sources in order to produce proteins, acids, etc
  • animals are heterotrophic (require external source of energy)
  • all physiological functions require energy and/or matter
134
Q

How much energy does an animal need?

A
  • enough to maintain basic metabolic functions
    -E.g., maintain cellular activity, blood flow, respiration, temperature
135
Q

How might an animal’s energy use be measured?

A

Heat production, oxygen consumption, carbon dioxide production, food consumption/waste production

136
Q

Which eats more? mouse or elephant?

A

depends on absolute/total amount or the body mass index
- elephant is larger - need more food overall
- mouse smaller = more activity - higher metabolism - mouse requires more food per kilogram, elephant has a lower BMR per kg

so mouse eats more per unit body mass
elephants eat more in absolute terms

137
Q

What functions are carried out by the digestive system?

A

ingestion: food handling
Digestion: break down of food into absorbable components
Absorption: nutrient molecules enter body cells
Elimination: removal of undigested material

138
Q

Why are structures associated with ingestion the most diverse?

A
  • Huge variety in sources of food - animals have evolved structures that allow them to exploit these various food sources
139
Q

What is the purpose of the epiglottis? When is it up?

A
  • acts as a ‘lid’ to trachea, up during swallowing to stop food from entering trachea as it goes to esophagus
140
Q

Does bile digest fat?

A

No, only breaks it down!

141
Q

An organ responsivee for absorbing food molecules should …

A

have large surface area and be well connected to the blood

142
Q

What animals have obesity as an evolutionary trait? Why is it important?

A

Seal pups become obese for a few weeks - they live off of blubber as they learn to swim and hunt

143
Q

what is diffusion?

A
  • molecules move randomly due to their kinetic energy
  • random movement causes a net flow from an area of high concentration to an area of low concentration
144
Q

How is diffusion related to distance?

A

Rate of diffusion inversely proportional to distance

145
Q

How is rate of diffusion related to surface area?

A

Rate of diffusion proportional to (surface area/distance)

146
Q

How do animals with many cells exchange materials with the environment? How about animals with most cells in contact with the environment?

A
  • some animals have body size and shape that allows most cells to be in contact with the environment = exchange is easy
  • animals with many cell layers require circulatory system to transport materials between all body cells and organs that exchange those materials with the environments
147
Q

What are the 3 basic components of the circulators system in all animals?

A
  1. circulatory fluid
  2. Set of interconnecting vessels
  3. a muscular pump
148
Q

Why do some materials only need to diffuse over short distances?

A

Only need to diffuse the distance it takes to get to the circulators system

149
Q

What are the two states a circulatory system can be?

A

open or closed

149
Q

Describe the circulatory fluid in closed and open systems

A

Blood in a closed circulatory system (mammals, etc)
- hemolymph in open circulatory systems

150
Q

Describe the circulatory system in mammals and birds

A
  • double circulation: two circuits flow to and from the heart
151
Q

Does deoxygenated and oxygenated blood mix in the heart?

A

NO!

152
Q

Describe the path of deoxygenated blood

A
  • returns from the systematic recruit via the superior vena cava, through the right atrium, inferior vena cava, into right atrium
  • right atrium contracts, blood pushed into right ventricle
  • right ventricle contracts, blood pushed into the pulmonary artery sending it to the lungs!
153
Q

Describe oxygenated blood’s path

A

returns from pulmonary circuit via pulmonary vein and flows into the left atrium
- left atrium contract, blood pushed into the left ventricle
- left ventricle contracts, blood pushed into the aorta sending it to the systematic circuit

154
Q

What do valves do?

A
  • ensure unidirectional flow of blood through the heart by closing to prevent back flow
155
Q

What are the kinds of valves? describe them.

A
  • atrioventricular valve (AV) = separate the atria from the ventricles and prevents back flow into atria when the atria relax
  • semilunar valves: separate the ventricle from the arteries and prevents back flow into ventricles when the ventricles relax
156
Q

What are the two states of the cardiac cycle?

A

Diastole = relaxation
systole = contraction

157
Q

What are the steps of the cardiac cycle?

A
  1. Atrial and ventricular diastole
  2. atrial systole and ventricular diastole
  3. ventricular systole and atrial diastole
158
Q

how does blood vessel structure reflect function? use capillaries to describe this

A
  • increased branching increases surface area: capillaries shave greater area than arteries and veins
  • Same volume of fluid flows more slowly through a greater area: velocity is slowest within capillaries
  • The increase in area in capillaries causes pressure to drop off: blood is not repressurised until it returns to the heart

So capillaries have greater area, less pressure, slower velocity

159
Q

What regulates blood flow?

A
  • nerve impulses, hormones and local chemicals that affect arteriole diameter and precapillary sphincters
  • at any time only 5-10 percent of capillaries have blood
160
Q

Why are capillary walls thing and have slow blood velocity?

A

allows for exchange of materials between blood and interstitial fluid

161
Q

What is blood? what are its components?

A
  • blood is a tissue consisting of cells suspended in a liquid called plasma
  • plasma (55%) = water, ions proteins, nutrients, metabolites, wastes
  • cellular elements (45%) = platelets, erythrocytes, leukocytes
162
Q

How are respiratory surfaces specialized for gas exchange?

A
  • gills, trachea, and lungs have very large surface area and thin change surfaced (single epithelial layer)
163
Q

Why does respiratory media vary in O2 concentration?

A
  • O2 based on source
  • air has high O2 concentration, water has lower O2 concentration
  • animals that obtain from water must be much more efficient
164
Q

Why do animals that breathe O2 from water need to be more efficient?

A
  • much lower concentration of oxygen ins ater
165
Q

How do gills work in terms of respiratory system ?

A
  • gills are efficient at extracting O2 but are unsuitable in terrestrial environemtns
  • respiratory surfaces must be moist
166
Q

How do the respiratory systems of gills and terrestrial animals differ?

A
  • respiratory media differs = different efficiencies
  • respiratory surfaces of terrestrial animals must be enclose to prevent water loss
167
Q

Know the mammalian respiratory system!

A
168
Q

What binds oxygen to red blood cells?

A

O2 binds to hemoglobin to transport in red blood cells

169
Q

How many oxygen binding sites does oxygen have?

A

4 bindings sites on hemoglobin

170
Q

What materials are red blood cells important for transporting? Describe the CO2 transport in the body

A
  • CO2 and red blood cells
  • CO2 produced in body cells travels :
    –> Bound to amino acids of hemoglobins (23)
    –> In blood plasma as CO2 (7)
    –> In blood plasma as bicarbonate (70)
171
Q
A
172
Q

To maximise diffusion rate, exchange surfaces should have…

A

C. a large surface area and be thin.

173
Q

What kind of animals do not require a circulatory system? Why?

A

One example is flatworms/planaria
- most cells are in direct contact with external environment so do not require circulatory system for exchange (particularly in aquatic environments)

174
Q

What are the two circuits involved in mammalian circulation?

A

Pulmonary circuit and systemic circuit
- pulmonary leads to lungs
-systemic leads to rest of body

175
Q

What are the differences between arteries and veins?

A
  • both made up of connective tussle and smooth muscle
  • arteries take blood away from heart to rest of body, are much thicker than veins
  • veins take deoxygenated blood back to heart, has valve
176
Q

Why do veins have valves but arteries don’t?

A

Arteries flow has high speed and pressure

177
Q

What are the two methods of body regulation in animals?

A
  • either regulate their physiological parameters or allow their bodies to conform to external conditions
  • regulators vs. conformers
178
Q

What are regulators?

A
  • use homeostatic mechanisms to control internal changes
179
Q

What are conformers?

A

allow for their internal condition to change in response to external changes
- may be able to tolerate greater ranges, internal stability is possible in stable environments

180
Q

Which regulation method has a greater capacity ?

A

generally conformers have a greater range and can tolerate greater ranges in conforming to their external temperature

181
Q

What does thermoregulation regulate? Osmoregulation?

A
  1. temperature
  2. body water, solute concentration
182
Q

What is thermoregulation? Why does it matter?

A
  • maintenance of an internal temperature within a tolerable range
  • temperature matters because biochemical and physiological recesses are sensitive to changes in temperature, each animals species has an optimal internal temperature range
183
Q

How might external temperature impair a body’s functioning?

A
  • inhibits physiological and chemical processes (enzymes eg) that can impair functioning and lead to death
184
Q

What is a poikilotherm?

A
  • body temperature varies with environment (most fish and reptiles)
185
Q

What are homeotherms?

A

Relatively constant body temperature (most mammals and birds)

186
Q

What are the 2 thermal strategies based on source of heat?

A

Endotherms: rely on metabolism as major heat source
and ectotherms : rely primarily on external environment as major heat source

187
Q

Are endotherms and poikilotherms isolated from each other?

A

no, endotherms can be poikilotherms and ectotherms can be homeotherms

188
Q

What does thermal regulation require?

A
  • equal rate of heat gain and heat loss
  • anatomical/physiological processes
  • behavioural responses
189
Q

What are the anatomical/physiological processes in thermoregulation?

A

Evaporative heat loss
Circulatory adaptations
Metabolic what production
Insulation

190
Q

Describe evaporative heat loss

A
  • water lost from most surfaces cools/carries heat away
  • augmentation: panting and sweating
191
Q

Describe circulatory adaptations

A
  • Vasoregulation: common to endotherms and ectotherms
  • Countercurrent heat exchanged in birds and mammals
192
Q

What is vasoregulation? Describe constriction and dilation

A
  • dilation or constriction of blood vessels achieved via nerve impulses and hormones
  • Vasodilation: relaxes smooth muscle walls of surface blood vessels = more blood flow to cool at surface
  • Vasoconstriction: tenses smooth muscles walls of surface blood vessels - reduces blood flow to prevent heat loss
193
Q

What is a counter current heat exchanger?

A
  • Heat is transferred between fluids in opposite directions
  • heat from warm arterial blood transferred to cooler venous blood as it return to body core
194
Q

What is a potential problem for the goose in maintaining body heat? What solves this?

A
  • feet are cold in water!
  • internal organs in the feathered area, specific counter current vessels that go to feet (cools as it goes down, heat as It goes back up)
195
Q

Describe metabolic heat exchangers

A
  • all metabolic activity produces heat - endotherms have much higher metabolic rate than ectotherms
  • muscle contractions: shivering, activity
  • brown adipose tissues - high concentration of mitochondria, cell reparation produces heat instead of ATP
  • hypothalamus thermostatic function in human thermoregulation
196
Q

Which animal with the same size, one an ectoderm and one an endotherm, would have a higher metabolic rate?

A
  • endotherm
197
Q

What is osmoregulation?

A
  • the control of solute concentrations and the balance of water gain and loss from the body
198
Q

Describe the homeostasis cycle

A

hot internal temperature –> signal sent to hypothalamus –> sends signals through hormones or nervous signals to produce sweat and/or vessels to dilate = temperate decrease

Low internal temperature –> hypothalamus triggers shivering = body temp increases

199
Q

What is insulation?

A
  • fur feather and fat are a major adaptation to maintain heat
200
Q

What are some behavioural adaptations to maintain thermoregulation?

A
  • shade seeking/sun basking, migration to cooler or warmer regions, nocturnal
201
Q

What might be some reasons for migration?

A
  • to maintain body temperature, or food/reosurce sources,
202
Q

would blubber in whales have more or fewer vessels than humans?

A

Fewer in order to prevent heat loss at the surface - keep blood and heat at internal organs, whales don’t often need to cool off

203
Q

What are the physiological parameters involved in osmoregulation?

A
  • body water (volume) eg:, blood, interstitial fluid, within cells
  • total solute concentration
  • individual concentration of solutes
204
Q

What are the solutes involved in osmoregulation?

A
  • calcium, potassium sodium, certain amino acids, water soluble hormones
205
Q

What is osmosis?

A
  • the movement of water across a selectively permeable membrane
206
Q

What is a hyper osmotic solution? A hypo osmotic solution?

A

Hyperosmotic solution: higher solute concentration, lower free H2O concentration
(hyperosmotic fluid)

Hyoosomtic solution: Lower solute concentration, higher free H2O concentration
(hypo osmotic solution)

207
Q

What is a hyper osmotic fluid in reference to animal cells?

A

higher solute outside of cells, water leaves cells by osmosis, cells shrivel and die

208
Q

What is a hypo osmotic fluid in reference to animals cells?

A
  • lower solutes outside cell (higher inside), water enters cells through osmosis, cells that gain too much water burst and die
209
Q

What is isoosmotic fluid? How would an animal cell react?

A
  • same solutes inside and outside, no net movement of water into or out of cells
210
Q

What are the two ways that animals maintain water balance?

A
  • osmoconformers : isosmotic with heir environment, no tendency to lose ro gain water, all are marine, some have stable osmolarities white others tolerate variable osmolatieis, actively transport specific solutes to maintain homeostasis

and osmoregulators:
- maintain a stable internal osmloarity
- found in marine, freshwater, and terrestrial environments
- particular osmolarity achieve by active transportation of solutes in or out, water follows

211
Q

How are energy costs of osmoregulation minimized?

A
  • reduced by minimizing osmotic differences between body fluids and surrounding environments
  • freshwater molluscs have lower internal osmolarities than Marine
212
Q

Why aren’t all animals osmoconformers?

A

Adaptation idk

213
Q

What are the osmoregulatory challenges of animals in different environments?

A

freshwater osmoregulatorys gain water
- marine osmorrgulators lose water
- terrestrial animals lose water

214
Q

Describe osmoregulation in marine fish

A
  • see diagram and notes
215
Q

Describe osmoregulation in freshwater fish

A
  • see diagram and notes
216
Q

Describe the osmoregulation of marine fish cells

A
  • marine fish are hypo osmotic relative to sea water (hyperosmotic fluid)
217
Q

Describe the osmoregulation of freshwater fish cells

A
  • hyperosmotic relative to the lake/river (hypo osmotic fluid)
218
Q

what are some terrestrial adaptations to prevent dehydration?

A
  • body coverings
  • nocturnal
  • maintain water balance by drinking and eating moist food and producing metabolic water through cellular respiration
219
Q

How do animals control the solute concentration of an internal body fluid?

A
  • transport epithelia: one or more layers of epithelial cells specialized for moving particular solutes in controlled amounts in specific directions
220
Q

Describe transport epithelia’s surface area. Why is it like this?

A

large surface areas, some face external environment directly (gills)
- many line tubular networks that connect to the outside by an opening on the. body surface.
- transport epithelia are closely connected to circulatory fluid

221
Q

Describe salt glands

A
  • Seabirds, sea turtles, and marine iguanas remove excess salt, taken in when drinking sea water, through salt secreting glands
  • Salt glands have transport epithelia that rely on countercurrent exchange
  • Salt concentration is always higher in the blood vessel than the secretory tubule
222
Q

Do transport epithelial cells have a large surface area or a small surface area? Why?

A

Large to aid in osmoregulation

223
Q

What is innate immunity?

A
  • recognition of traits shared by broad ranges of pathogens, using a small set of receptors
  • rapid response
  • has barrier defences and internal defences
224
Q

Can innate immunity be found in invertebrates?

A

YES. It’s found in all animals.

225
Q

What are the barrier defences of innate immunity?

A

skin, mucous membrane, secretion

226
Q

What are the internal defences of innate immunity?

A
  • phagocytic cells, natural killer cells, antimicrobial proteins, inflammatory response
227
Q

What is adaptive immunity? where is it found?

A
  • recognition of traits specific to particular pathogens using a vast array of receptors
  • slower response
  • has humeral response and cell mediated response
  • found in vertebrates only
228
Q

Describe the responses in adaptive immunity

A
  • humoral response: antibodies defend against infection in body fluids
  • Cell mediated response: cytotoxic cells defend against infection in body cells
229
Q

What are barrier defences?

A
  • prevent most pathogens from entering the body
  • skin/shells/cuticle: thickened outer surface inhibits entry by pathogens
  • mucous membranes: mucus secreted by internalized external surfaces traps microbes and other particles
  • secretions: saliva, tears - washing actions prevents microbial colonisation, hostile chemical environment (lysosome, acidic pH )
230
Q

Describe phagocytotic cells

A
  • recognize molecules characteristic of a set of pathogens, destroy pathogens by phagocytosis
  • recognize molecule is absent from vertebrates and is an essential component of certain groups of pathogens
231
Q

Why is it important for the component of the pathogen recognize by phagocytosis cells to be essential to the pathogen?

A

If it wasn’t essential for the pathogens natural selection would weed it out and the pathogen would still survive and evade detection

232
Q

How do phagocytosis cells destroy pathogens?

A
  • recognize pathogen, destroys through phagocytosis
  • located in the blood, skin, mucous membranes, lymph
233
Q

What are natural killer cells?

A

-component of internal defence
- recognize surface proteins of virus-infected or cancerous cells
- release chemicals that cause adopts in infected/cancerous cells

234
Q

What are antimicrobial proteins? Provide 2 examples

A
  • component of internal defence
  • attack pathogens or impede their production
  • ex: interferons and complement proteins
235
Q

How do interferons and complement proteins work?

A
  • interferons: secreted by virus infected cells, trigger surrounding cells to produce chemicals that inhibit viral reproduction
  • complement proteins:
    1) plasma proteins activated by substance on surface of microbe,
    2) leading to lysis of invading cells,
    ** also involved in inflammation and adaptive immunity
236
Q

Describe local inflammation. What are some examples of stuff released in local inflammation?

A
  • signalling molecules released by injured or infected tissue causing local inflammation
    eg; histamine and cytokines
  • signalling molecules cause capillaries to dilate and increase blood flow
  • phagocytosis cells (neutrophils) activate complement proteins and other antimicrobial proteins to fight infection
237
Q

What are the two kind of inflammatory response?

A
  • local inflammation and systemic inflammatory responses
238
Q

Describe the signalling molecules for local inflammation

A

Histamines: triggers vasodilation and increased blood vessel permeability in affected area = more white blood cells an proteins

Cytokines: further increased blood flow to the affected area

239
Q

Describe the systemic inflammatory response

A
  • triggered by serious infection
  • release more white blood cells from the bone marrow, reset body’s thermostat (fever)
  • send more blood to required areas (swelling)
240
Q

Where are white blood cells created?

A

bone marrow!

241
Q

What component are used to fight infection in small infection?

A
  • complement proteins and other antimicrobial proteins
242
Q

Describe adaptive immunity

A
  • involved pathogen specific recognition
  • specificity achieved through interactions between antigen and antigen receptors
243
Q

What are antigens?

A
  • large molecules found on the surface of specific pathogens or secreted by those pathogens
  • antigens contain multiple epitopes (a small accessible portion of an antigen that binds to an antigen receptor)
244
Q

What are antigen receptors?

A
  • proteins produced by B cells or T cells
245
Q

What are B cell and T cells?

A
  • lymphocytes
  • Each B or T cell produces a single type of antigen receptor
  • each antigen receptor binds to a single epitope of a single antigen
  • variable regions of antigens receptors produce the specific of the antigen binding site
246
Q

What are lymphocytes? Where do they mature?

A
  • white blood cells produced in the bone marrow
    – Be cells mature in the bone marrow, T cells migrate to the thymus for maturation
247
Q

What is the humoral response?

A
  • B cell antigen receptors bind to intact antigens in the blood or lymph
  • these antigens may be on the surface of pathogens or may be antigens secreted by pathogens
248
Q

What is the cell mediated response?

A
  • T cell antigen receptors can only bind to antigen fragments presented on the surface of the host cells
249
Q

Describe the proliferation of B and T cells

A
  • B cells and T cells proliferate when they encounter their specific epitome
  • proliferates into memory cells and effector cells
250
Q

What are memory cells?

A
  • result of proliferation of B and T cells
  • long lived cells that give rise to effector cells if the same epitope is encountered again
251
Q

What are effector cells?

A
  • short lived cells that take effect immediately against the pathogen or antigen
252
Q

What are antibodies?

A
  • effector forms of B cells are plasma cells which secret antibodies
  • soluble forms of the antigen receptor: specific for the same epitope as the original B cell
  • mark pathogens for inactivation or destruction
253
Q

What happens when antibodies mark pathogens for inactivation?

A
  • neutralizations prevents pathogen entry into cells
    toxins can also be neutralised by antibodies
  • Opsonisation: Antibody binding increases the ability of phagocytic cells to recognize the pathogens
  • Leads to increased phagocytosis of pathogens
254
Q

What causes pore formation?

A

-antibodies activate complement system

255
Q

What are the effector forms of T cells?

A
  • effector forms of T cells are helper T cells and cytotoxic T cells
  • cytokines from Helper T cells help activate B cells and cytotoxic cells
  • Cytotoxic T cells secrete proteins that lead to cell death
256
Q

What do cytoxic T cells do?

A

Bind to infected cells and secrete perforin and granzymes

Perforin: causes pores to form in cell membrane of infected cells
Granzymes: initiate apoptosis

257
Q

What is the primary response to antigen A?

A
  • produces antibodies to A
258
Q

What is the secondary immune response to antigen A?

A
  • produced antibodies to A, primary immune response to antigen B produces antibodies to B
259
Q

What are the 3 kinds of skeletal structures?

A
  • hydrostatic: fluid under pressure compressed within closed comaprtment
  • endoskeleton: hardened internal skeleton
  • exoskeleton: hardened external skeleton
260
Q

How do skeletons and muscles coordinate movement?

A
  • skeletons generate movement by using muscles attached to hard parts of the skeleton
261
Q

What are antagonistic muscles?

A
  • antagonistic muscles are pairs of muscles which oppose each others movement across a joint
    eg., triceps and biceps
262
Q

Describe the hierarchal organization of musculoskeletal system

A

skeletal muscle –> muscle fibres (AKA multi nucleated cells) –> myofibrils –> sarcomere (myosin and actin)

263
Q

Describe the thin and thick filaments

A

Thin filament = actin, double strand
Thick filament = myosin (molecules of myosin with heads exposed)
- compose sarcomere, held by 2 lines, striated muscles

264
Q

How does actin and myosin filaments move against each other?

A

they slide against each other
mason uses ATP to bind to receptor sites on actin and uses actin to move toward centre of sarcomere

265
Q

How does the skeletal muscle know when to contract?

A
  • skeletal muscle contraction intimated by motor neurons
  • stimulates release of Ca2+ which binds to troponin complexes, moves tropomyosin to expose binding sites on actin filament which allows for myosin binding (and muscle contraction)
  • troponin complex binds with calcium and moves the tropomyosin to expose the active site on actin
266
Q

What is locomotion? What forces play a part in locomotion?

A

locomotion: active travel form place to place
- to move animal must overcome gravity and friction forces
- environment determines which is the dominant force to overcome (air/terrestrial=gravity, water=friction (drag) )

267
Q

How does natural selection impact locomotion?

A
  • natural selection develops adaptations that reduce the energy needed for locomotion
  • both behavioural and anatomical adaptations : slow descent in water, springy tendons, fusiform body shape, etc.
268
Q

Describe locomotion on land and the adaptations

A
  • gravity is the dominants force opposing motion on land
  • terrestrial animals develop strong skeletal muscles and muscles to stay upright
  • maintain balance: 2 legs vs. multilegs
  • adaptations: springy tendons
269
Q

Describe locomotion in air

A
  • dominant force to overcome is gravity
  • wing lift must overcome gravitational downward pill
  • adaptations : flying animals are lighter and have fusiform shape (birds have no teeth, no bladder, air in bones)
270
Q

Describe locomotion in water

A
  • most aquatic animals buoyant = easy tor resist gravity, but water is dense/viscous so drag (friction) is a problem
  • adaptation: fusiform body shape reduces drag
271
Q

What is the functional unit of the muscle?

A

the sarcomere (composed of filaments : actin and myosin)

  • entire chain is myofibril, made up of sarcomere, filaments of sarcomere held by Z lines
272
Q

Does the actin and myosin of a sarcomere change length in muscle contraction?

A

no, the sarcomere shrinks but the filament does not change length
- the filaments CHANGE LENGTH, and overlap but do not shrink : length of filaments remain the same while the muscles become a littler shorter and fatter

273
Q
A

bio (11 decks)

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