Muscles Tissues And Movement Flashcards
What is homeostasis?
the tendency for an organism to maintain a constant internal environment even if there’s changes in the external environment
What are the three components of a negative feedback loop?
Sensor, control, effector
What is an example of a smooth muscle?
Vein
What is the structure of a smooth muscle?
Parallel lines form sheets
Have one nucleus
Doesn’t have striations of skeletal muscle because the actin and myosin
doesn’t have the striations
filaments are not regularly placed along the length of a fibre, and contains less myosin
Where are smooth muscles found?
In the walls of blood vessels around bronchioles in lungs, all through the digestive system, and the iris
of the eye
Do smooth muscles contract voluntarily or involuntarily?
Involuntarily
Are cardiac muscle cells striated?
Yes (bands of light and dark)
How many nuclei do cardiac muscles have?
1
What is the structure of cardiac muscle
they are branched and can contract by themselves - the pacemaker of the heart basically serves to coordinate the contraction
Have one nucleus
How does skeletal muscle differ from cardiac muscle
It’s striated like cardiac muscle but unlike cardiac muscle it’s cells contain many nuclei and are under voluntary control
Are skeletal muscles under voluntary or involuntary control?
Voluntary
What is the structure of skeletal muscle cells
Cells are very long (up to 20cm in length) and have multiple nuclei to coordinate the functions of these cells. They are often referred to as fibres rather than cells.
