Animal: Lecture 1 Flashcards
What are the 5 core concepts of biology related to animal development and physiology?
- Structure & Function (shape and makeup affects function directly)
- Evolution (how they appear?)
- Systems (all connected)
- Information Flow (chemical or electrical)
- Transformations of Energy and Matter (we need energy and it needs to be useable)
What is an animal?
- Heterotrophic
- Multicellular
- Mitochondria
- Lack cell walls
- Regulatory (Hox) genes
- Movement at some point in development
What are the functions that animals need to carry out?
- Reproduction and development
- Cellular respiration/gas exchange between internal and external environments
- Digestion
- Sleep
- Excretion
- Obtain matter and energy and transport the energy throughout the body
- Protection from external environment or pathogens or heat or cold, etc.
- Maintenance of water & salt concentrations in the internal environment
- Support and movement of the structures that we need to keep upright and moving
- Coordination of bodily functions, without having to think about every little thing.
How is structure related to function?
Hierarchical Organization: from small to large!
Hierarchical organization?
- Molecules
- Cells
- Tissues
- Organs
- Organ systems
- Organisms
Molecules?
4 main molecules:
- Nucleic acids
- Lipids
- Proteins
- Carbohydrates
Organelles?
Each have a distinct function in a cell:
- Mitochondria
- Nucleus
- Cell Membrane
- ETC
Tissues?
Similar cells groups together to serve a certain purpose. Tissues are usually held together through a kind of matrix, like fibres or membranes. Connective tissues like bones, cartilage, or blood.
Types of tissues?
- Epithelial - lines the surfaces of the body
- Muscle - made up of fibres that contract
- Nervous - cells with projections that transmit electrical signals
- Connective
- loose connective tissues as a padding under skin, etc.
- bones and cartilage
- blood is made up of cells in a liquid matrix
Organs?
Structures that serve a specific purpose:
- Stomach
- Liver
- Lungs
Organ systems?
- digestive
- circulatory
Organisms?
fully functioning, the biggest structure!
How is structure related to function?
Structure enables function:
- A structure’s physical and chemical characteristics influence its interactions with other structures, and therefore its function.
What are functional trade-offs?
Specialization for one function may limit a structure’s ability to perform
another function
- It is impossible to optimize for all parameters
Examples of functional trade-offs?
Organisms that mainly have cartilage in their bodies:
- high flexibility
- low strength
Organisms mainly with bone:
- low flexibility
- high strength
Why might functional trade-offs occur?
We might be well-suited for one thing, but not well-suited for another thing.
- Through evolution, certain features favour one direction, while other features favour different directions
- The best one that leads to the most survival will be chosen/persist
What kind of structure will be best for allowing molecules to move between two compartments?
(B) Three layers, all very thin. Allows easy transport of materials between the layers as it takes less time.
Evolution of structures?
Through natural selection, organisms become more adapted to their environment.
- Usually some type of evolutionary pressure on the species when this occurs…
Example of evolving structures?
Fish with spiky backs vs. smooth:
- Invasive species that is very quick comes in
- Influences the fitness of the population. faster = more survival = fitter population
- Better structures in an environment might be passed on for that function
- therefore, individuals with functions that persist are much more well-adapted
Grey Seal structure?
- Not well suited to land environment, as it is hard for them to move very fast or well.
- Really well-suited to the water. fusiform body has fat and blubber for insulation in water and for buoyancy as well.
Structure and environment?
Structures make sense in context
of the animal’s environment
How do we know if something is an animal?
- multicellular
- heterotrophic
- movement
- no cell walls
- hox genes
- coordination
- reproduction
Biological structures interaction?
- Molecules:
Proteins, lipids, carbohydrates, and nucleic acids are organized into… - Organelles:
Which make up the… - Cells:
are organized into… - Tissues:
Four tissue types (epithelial, muscular, connective, nervous) combine in different ways to form the… - Organs:
Which work together as… - Organ Systems:
That carry out a larger function, and together they carry out all of the physiological functions of the… - Organisms:
Change in structures/components?
A change in one component of a network can affect many other components
- Even if they are in a hierarchical kind of set-up, these structures interact with each other within these complex systems.
Example (knee issue)?
Cells:
- changes at the molecular and cellular level trigger
Tissues:
- degradation of cartilage
Organs:
- knee injured
Organ systems:
- Musculoskeletal system must compensate
Oganism:
- locomotion is compromised
What are emergent properties?
Each level of organization has properties not exhibited by lower levels
- each time, it becomes more capable of completing more tasks or completes them more effectively.
Example of emergent properties?
E.g., Structure → emergent property
– Cardiac muscle (tissue) → contracts
– Cardiac muscle + other tissues = heart (organ) → coordinated pumps
– Heart + vessels + blood = circulatory system
→delivers O2 around the body
i.e., muscle alone cannot pump heart; heart alone cannot deliver O2
Which of the following represents a “structure ~> emergent property” pairing?
A. Cell ~> life
B. Foot ~> walking’
C. Nose ~> sense of smell
D. Sugar ~> facilitated diffusion
CORRECT ANSWER: A
What cells exchange materials with the external environemnt?
All cells must exchange material
with the external environment
Simple organism exchange?
- Some animals are structurally simple enough that all cells are in direct contact with the external
environment
E.g. Hydra: two layers of cells. Internal fluid and external fluid exchange materials through 2 layers.
More complicated organisms?
More complicated bodies require organ systems that:
− can exchange material with the external environment
− can transport material around the body
Systems that exchange with external environment?
- Digestive system (eat)
- Excretory system (poop)
- Respiratory system (breathe)
- Integumentary system (sweat)
Systems that exchange within the body?
Circulatory system - blood!
Small intestine shape?
Well-suited to function. Job is to absorb things, therefore they have a large surface area and a small volume.
Lung tissue shape?
Very porous, small layers of tissue are therefore good for the gas exchange.
Interstitial fluid?
Body is wet to facilitate movement.
- Between organs and systems
- Facilitates exchange of nutrients and gases.
communication systems for animals?
Animals have systems that perceive
and respond to changes in their
internal and external environments
Perception and response requires communication? What kinds?
All perception and response requires information flow (aka communication):
– Chemical and/or electrical signaling between cells coordinates responses at the cellular, tissue, organ, and system levels
What systems work toward communication?
Endocrine (hormone) and nervous (nerves) systems are the major
systems that control responses to stimuli & coordinate body activities
What is homeostasis?
Homeostasis is the maintenance of a
relatively stable internal environment in animals regardless of external situation or environment
Set point?
Set point is the area where animals like to be between (range of effective points for animals to function properly and well).
Why is a stable environment important?
Cells have conditions under which they function optimally.
- Enzymes and membranes are sensitive to changes in their surroundings (pH or temperature)
What does homeostasis rely on?
Homeostasis relies on negative feedback to maintain a set point.
Negative feedback?
Negative feedback is a control mechanism in which the response opposes the original stimulus.
- MOST of our systems are this way
Positive feedback?
Positive feedback is a control mechanism in which the response reinforces the original stimulus.
Ex:
- Hormones contract uterus, contractions produce more hormones, therefore having more contractions
- Suckling motion enhances hormones, therefore more milk is produced, leading to more suckling and more milk production
Which are examples of negative feedback?
A. Our bodies sweat to cool down when we are hot
B. An excessively high concentration of a molecule inhibits its production
C. Uterine contractions during labour lead to stronger uterine contractions
D. High blood CO2 triggers more rapid breathing
CORRECT: A,B,D
Regulated changes in physiological parameters are essential to?
Regulated changes in physiological
parameter set points (and their normal ranges) are essential to normal body functions
Examples of regulated changes?
Stage of life
– E.g., Puberty
Cyclic
– E.g., Menstrual cycles, Circadian rhythm
Response to environmental change
– E.g., Acclimatization
All physiological functions require?
ENERGY
Food is how animals obtain..?
Food is how animals obtain:
– chemical energy (e.g., sugars, fats, proteins; energy stored within bonds)
– and molecular building blocks (e.g., amino acids)
Stored chemical energy is..?
(Stored) chemical energy is converted to ATP:
– Also stores energy within bonds (aka chemical energy)
– Needed to carry out the cellular work necessary for physiological activities
Natural selection favours the evolution of..?
The efficient use of resources, within constraints.
Organisms have limited energy and material resources:
– Requires efficient allocation across competing functional demands
Resource trade-offs?
– E.g., Reduced capacity for wound healing when producing eggs
– Reproductive function often
takes precedence.
Resource trade-offs: grey seals?
Wait to digest food when oxygen is not limited.
Which of the following is an example of a trade-off? What kind?
A. The ability of skin to protect is limited by its need to exchange materials
B. Animals that produce many offspring at once provide little care for those offspring
C. Overtraining in elite female athletes can cause them to cease menstruating
ANSWER: All are trade-offs!
A. functional trade-offs
B. life-history trade-offs
C. resource/energy trade-offs
Animals?
Animals are multicellular heterotrophic organisms that lack
cell walls, can move, and possess Hox genes.
Animals need to?
Animals need to reproduce and develop; obtain and transport matter and energy into and throughout the body; exchange gasses; protect themselves from the external
environment and pathogens; maintain internal water and
solute concentrations; support and move themselves; and coordinate their bodily functions.
Animal body structures?
Animal body structures are related to their functions and vice versa and form complex systems.
Animals have systems..?
Animals have systems that perceive and respond to changes
in their internal and external environments.
Homeostasis?
Homeostasis is the maintenance of a relatively stable internal environment and relies on negative feedback.
Physiological energetic requirements?
Physiological energetic requirements of animals are obtained through the consumption of food that is transformed/stored/converted to ATP.
Natural selection?
Natural selection favours the evolution of efficient use of
(limited) energy and resources, with trade-offs.
