CFR 1 Notes

These flashcards cover key concepts related to the cardiovascular system, biological fluids, renal function, and homeostasis from the lecture notes.

What is homeostasis?

Homeostasis is the maintenance of constancy in the body.

What do the Greek words for 'homeostasis' mean?

They mean 'same' and 'steady'.

What are homeostatic control systems?

Compensation mechanisms that help maintain a stable internal environment.

What can disrupt homeostasis?

Changes to the internal and external environments.

What are the two types of feedback systems?

Negative feedback and positive feedback.

What occurs during negative feedback?

It reverses a change in the variable by reducing the intensity of the stimulus.

Can homeostatic control systems maintain a variable at complete constancy?

No, they cannot; regulated variables have a range of normal values.

What is an example of a variable controlled by homeostasis?

Body core temperature.

What happens during a positive feedback system?

The response enhances the original stimulus.

In the context of homeostasis, what is a variable?

A factor or condition being regulated, such as blood pressure.

How does the body communicate for homeostatic control?

Through the nervous and endocrine systems using electrical impulses and hormones.

What is denaturation?

When proteins lose their functional shape due to environmental changes.

What are two diseases associated with protein denaturation?

Alzheimer’s Disease and Creutzfeldt-Jakob Disease.

What is the role of receptors in a feedback system?

To monitor changes in a variable and send input to the control center.

What does the control center in a feedback system do?

Determines the set-point for a variable and generates output commands.

How do effectors work in the feedback system?

They receive output from the control center and produce a response that changes the variable.

What is an example of a negative feedback mechanism in the body?

Regulation of blood pressure.

What triggers the release of oxytocin during childbirth?

Uterine contractions causing the cervix to open.

What is acclimatization?

A reversible adaptation to prolonged exposure to an environmental stress.

What does a feedback loop do after a response occurs?

It influences the effect of the stimulus to either shut off or enhance the process.

What is the average normal body temperature?

37°C with a range of 36.1-37.2°C.

What is the impact of aging on homeostasis?

Aging can disrupt homeostatic mechanisms, leading to imbalances.

What contributes to severe homeostatic imbalances?

Excessive stress and extreme environmental conditions beyond control.

What is an example of a physiological variable that is not homeostatically regulated?

Heart rate.

What is the normal range of blood pressure derived from?

Controlled variables such as heart rate, stroke volume, and peripheral resistance.

What is the first step taken by the body when blood pressure increases?

Baroreceptors detect higher blood pressure.

What is the function of biological rhythms?

They provide an anticipatory control component to homeostatic control systems.

What happens to body temperature during sleep?

It decreases.

What role does the hypothalamus play in biological rhythms?

It controls internal biological rhythms.

What can affect biological rhythms?

Light exposure.

What is a sign of disease?

Objective changes such as fever or swelling.

What distinguishes a symptom from a sign in disease?

Symptoms are subjective changes, such as headache.

What occurs when insulin is no longer produced in Type 1 Diabetes?

Blood glucose continues to rise and can become fatal if not treated.

What is an example of positive feedback in the body?

Blood clotting.

How is heart rate involved in regulating blood pressure?

It contributes to blood pressure regulation but is not controlled around a set point.

How does the body maintain homeostasis under intense heat?

Through increased sweating and other cooling mechanisms.

What happens to homeostasis during a fever?

The body temperature set point is raised to help fight infection.

What are the main components of a feedback system?

Receptor, afferent pathway, control center, efferent pathway, effector.

How do homeostatic control systems protect proteins?

By maintaining the internal environment within tolerable limits.

What is the effect of extreme environmental conditions on homeostasis?

It can lead to severe disruptions in homeostatic balance.

Give an example of an anticipatory response in homeostasis.

Body temperature increases before waking in a sleep-wake cycle.

What is the human body’s response to a drop in blood glucose?

It activates hunger and stimulates eating to restore glucose levels.

Why is understanding homeostasis essential for health?

Human health depends on the proper functioning of homeostatic mechanisms.

What happens if a homeostatic imbalance is not treated?

It can lead to illness or death.