Animal Form and Function Flashcards
What is environmental exchange?
Animals must exchange nutrients, waste products and gases → further limitations on body size and shape
- Rate of exchange is proportional to surface area, while amount of material that needs to be exchanged depends on volume
What are the approaches that animals have for environmental exchange
» Optimise body shape for exchange
» Develop specialised exchange surfaces and a circulatory system
How do animals optimise their body shape for environmental exchange
Some animals have body shapes that allow them to put many of their cells in contact with the environment → can still rely on diffusion, Which makes it easier to have environmental exchange
What are two examples of animals optimising their body shape for environmental exchange?
» eg gastrovascular cavity in hydras, jellyfish and other cnidarians
» eg flat body in planarians
Draw the two types of gastrovascular cavity in hydras
in work book
Why are there more systems in more complex animals?
- Complex organisims have multiple systems that have specialised surfaces which increase surface area for environmental exchange.
- These include: respiratory system, digestive system, excretory system and circulatory system
What is the relationship between the exchange surfaces and the circulatory system?
- Respiratory system brings in oxygen from the environment and uses it to oxidize the blood for our organs and releases CO2 back into the environment.
- Digestive system brings in food from the environment which provides nutrients. This is absorbed by microvili and sent into the blood stream to be taken around the body.
- Excretory system takes waste products out of the blood (kidneys) and this goes back into the environment
Draw the Exchange surfaces and circulatory system diagram.
in work book
What are the benefits of a more complex body plan
Despite challenges of exchange, complex body plans have several advantages over simpler ones
» External skeleton protect ≠ predation
» Sensory organs provide detailed information about environment
» Internal digestive organs digest food gradually, controlling energy storage
» Maintaining body internal environment allows living in a variable external environment
How many types of tissue are cells divided into
Cell are organised into 4 types of tissues
What are the four types of tissue
» Epithelial: sheets of cells that cover the outside of the body and line organs and cavities inside the body
» Connective: spare cells embedded in extracellular matrix; binds and supports other tissues
• Loose or fibrous connective tissue, cartilage, bone, adipose tissue, blood
» Muscle: filaments of actin and myosin, which work together to enable contractions; responsible for nearly all types of body movement
» Nervous: receive, process and transmit information
What are organs made up of?
multiple types of tissues
- eg. skin is made of fat, connective tissue, etc
What are organ systems made up of?
- Groups of organs that work together to make up an organ system
- there are usually 7 organs that make up an organ system
eg. digestive system
What are the major organ systems?
There are 11 and they are based on what an animal need to do to survive
- Obtain nutrients and oxygen: Digestive, respiratory, circulatory, excretory
- Fight off infections: Integumentary, immune
- Produce offspring: Reproductive
We also have to have systems that allow us to have these systems run smoothly which are:
- Coordinate body functions: Nervous, endocrine
- Move: skeletal, muscular
What does an animal need to be able to coordinate body functions?
- Tissues, organs and organ systems must work together -> need coordination
What are the two internal communication systems?
- Endocrine
- Nervous
What is the Endocrine system?
- Signalling molecules (hormones) are released into the blood stream and carried to all locations in the body
- Only cells that have receptors for that specific hormone respond
- Hormones remain in blood for min to hours → long lasting effect
What is the nervous system?
Neurons transmit signal (nerve impulse) along dedicated routes (axons) to specific locations
» Can act on other neurons, muscle cells, cells and glands that produce
secretions
- Extremely fast communication, and effect only last a fraction of a second
How do nerve impulses travel?
A Nerve impulse will travel a long distance along an axon as a change in voltage (electrical signal) and will travel a short inter-cell distance as a chemical signal (neurotransmitter)
What is the difference between the endocrine system and the nervous system?
Endocrine and nervous system differ in signal type, transmission, speed and duration → which are all adapted to their different functions
What are the effects of the Nervous and Endocrine systems?
- Endocrine:
» Gradual change that affect whole body, such as growth, development, reproduction, metabolism, digestion - Nervous:
» Immediate and rapid responses to environment, such as reflexes and movement
What is homeostasis?
To maintain a stable environment
Why is it important to have homeostasis?
so that there is a stable environment is perfect for our cells to do their work
How is Homeostasis achieved?
Achieved via feedback control
» Sensor
» Control center (compare to set point)
» Effector (response)
