struc and func of human body

Epithelial tissue

Forms a protective layer covering the body and its organs. It plays roles in absorption, secretion, and sensation.

Connective tissue

For structure and support

Muscle tissue

Responsible for movement and contractility

Neural tissue

Responsible for transporting signals to cause a response

Homeostasis

Maintenance of a stable internal environment in the body despite external changes.

Negative feedback

Reversing the change caused by a stimulus to reach optimal conditions

Insulin

• secreted by beta cells when blood glucose levels are high

• causes glycogenesis

Glucagon

• secreted by alpha cells when blood glucose levels are low

• causes glycogenolysis and gluconeogenesis

Metabolic rate

Amount of energy used by a person per unit of time

Basal metabolic rate

Amount of energy per unit of time that a person needs to keep the body functioning at rest

Catabolism

Breaking down molecules into smaller units

Anabolism

set of metabolic pathways that construct molecules from smaller units

Gluconeogenesis

Generation of glucose from certain non-carbohydrates carbon substances e.g. amino acids and glycerol

Outline the sliding filament hypothesis

• action potential arrives at nerve cell

• calcium released into sarcoplasmic reticulum

• calcium binds to troponin

• tropomyosin undergoes a conformational change

• myosin binding sites on actin are exposed

• myosin heads bind and form cross bridges

• myosin heads perform a power stroke

• filaments are pulled past each other

• ATP is required to detach the myosin head