Coordination in humans Flashcards
Give two examples of homeostasis
Osmoregulation (body water content)
Thermoregulation (body temperature)
What is thermoregulation
Temperature regulation
Why is thermoregulation important?
Enzymes denature if temp too high
Cell membranes become fragile as temp rises
Diffusion rates rise with night temps and fall with lower temps
Liquids such as blood become more viscous (thicker) as temp falls
What controls thermoregulation
The hypothalamus
Protective functions of the skin
Tough water proof barriers between body and external environment
Regulates body temp
Contains sensory receptors to detect external environment changes
Protection from infection
What are the two main layers in the skin
The upper epidermis and lower dermis
What is the function of melanin
Absorbs ultraviolet light and protects the cells DNA from damage
Mammals and birds are what?
Endotherms
What can endotherms do
Maintain an internal environment that doesn’t change when external environmental temperatures change
Amphibians reptiles insects and fish are what
Ectotherms
Why can endotherms survive extreme temperatures better?
Temperature affects Ectotherms a lot more
Which animal will lose heat more quickly. A mouse or an elephant?
A mouse because it has a big surface area to volume ratio
What happens to sweat glands in the cold?
Sweat is not produced so sweat doesn’t move onto skin surface
What happens to sweat glands in hot temps
Sweat produced, water in sweat evaporates from the skin. This uses heat energy from the blood which will reduce heat energy and so cool you down
Why is it important for organism to control their internal environment?
So enzymes can control cell function and enzymes need specific conditions to work efficiently
