Human Body, Systems and Homeostasis

This set of flashcards covers key concepts related to the human body, systems involved in homeostasis, and various feedback mechanisms.

Homeostasis

The tendency of the body to maintain a relatively constant internal environment.

Survival Range

The human body can only survive within a narrow range of conditions.

Feedback Systems

Systems that monitor internal changes and maintain homeostasis.

Sensor

Component that detects changes in the internal environment.

Control Centre

Sets the range of values for a variable to be maintained.

Effector

Responds to signals from the control center to effect change.

Negative Feedback

Output of a system reverses a change in a variable.

Vasodilation

Widening of blood vessels to decrease body temperature.

Hypothalamus

Brain region that regulates body temperature.

Diaphoresis

Process of sweating to cool down the body.

Vasoconstriction

Narrowing of blood vessels to increase body temperature.

Blood Glucose Level

Normal blood glucose level is about 90 mg/100 ml.

Insulin

Hormone that stimulates glucose uptake by cells.

Glucagon

Hormone that stimulates glycogen breakdown.

Menstrual Cycle

Regulated by positive and negative feedback loops involving hormones.

Positive Feedback

Output of a system strengthens or increases a change in a variable.

Oxytocin

Hormone that stimulates uterine contractions during childbirth.

Blood Pressure Homeostasis

Mechanisms to maintain normal blood pressure.

Cardioacceleratory Centers

Stimulated to increase heart rate.

Cardioinhibitory Centers

Inhibited to decrease heart rate.

Baroreceptors

Sensors that detect changes in blood pressure.

Child Birth Reflex

Positive feedback loop involving oxytocin and cervix stretching.

Ethylene Production

Gas produced by ripening fruit that triggers more fruit ripening.

Lactation

Positive feedback loop involving breastfeeding and hormone release.

Thermoregulation

Maintenance of body temperature optimal for cell function.

Endotherm

Animal that generates metabolic heat to maintain internal temperature.

Ectotherm

Animal whose body temperature changes with the environment.

Homeotherm

Animal that maintains a stable body temperature.

Poikilotherm

Animal whose body temperature varies with the environment.

Conduction

Transfer of thermal energy through direct contact.

Convection

Transfer of thermal energy within a fluid.

Radiation

Transfer of thermal energy as electromagnetic radiation.

Evaporation

Loss of heat due to water evaporating from the skin.

Torpor

Short-term state of decreased metabolic rate and body temperature.

Estivation

State of torpor that allows survival during summer.

Hibernation

State of greatly reduced metabolic rate and activity.