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Factors that increase metabolic rate and heat production

By: HWC, Views: 6648

• All vital biochemical reactions are temperature dependent. • The overall rate at which metabolic reactions use energy is known as the metabolic rate. • Metabolic rate greatly determines body temperatures. • Temperature is maintained by balancing the loss of heat to the environment...

Metabolic Rate, Heat and Thermoregulation - response to heat and cold stresses

By: HWC, Views: 6856

• A neuron group in the anterior portion of the hypothalamus controls heat balance. • Neurons in the preoptic region of the hypothalamus integrate signals that come from thermoreceptors. • The temperature control center in the preoptic region propagates control signals to two other part...

TRH/TSH/Thyroid hormone

By: HWC, Views: 6213

Thyroid hormone production • A decline in metabolic rate caused by increased metabolic need or physical exertion stimulates the production of thyrotropin hormone releasing (TRH) hormone from the cells of the hypothalamus. • Thyrotropin hormone releasing hormone targets the thyrotrophic ce...

The Hypothalamus: The Body's Thermostat (Human Thermostat)

By: HWC, Views: 5883

Normal body function requires a relatively constant body temperature, which is regulated by the body's thermostat, a region of the brain called the hypothalamus. The hypothalamus generates a temperature set point for the body and appears to be the major site for the integration of temperature inf...

Effect of the environment on coat color in the Himalayan rabbit Animation

By: HWC, Views: 2234

An organism's phenotype—the combination of traits that we observe—is the product of interactions between its genotype and the environment. For example. a Himalayan rabbit is completely white at birth. But within weeks, the fur on the rabbits ears, nose, tail. and lower legs darkens. The...

Acid-base imbalances - compensation of metabolic acidosis and alkalosis

By: HWC, Views: 6916

1. Metabolic acidosis: • Few HC03- ions are present so blood pH becomes acidic. • Compensation is increased respiratory rate and more CO2 is removed from the blood. • Blood pH returns to normal. 2. Metabolic alkalosis: • Many HC03- ions are present so blood pH becomes alkaline...

Exercise and cardiac output & Definition of stroke volume

By: HWC, Views: 6608

▪ Cardiac output: • Maintains blood flow throughout the body. • Measure of blood volume ejected from the heart over a given time. • Determined by multiplying heart rate by stroke volume (CO = SV x HR). • Heart rate: Number of beats/min. • Stroke volume: Amount of blood eject...

The primary factors that affect circulation - MABP, CO and SVR

By: HWC, Views: 6931

Introduction Blood flow is determined by the relative intensities of factors that drive and resist moving blood. • Cardiac output (CO) equals the mean arterial blood pressure (MABP, a driving force) divided by systemic vascular resistance (SVR, a resisting force). • Hormones and the cen...

Definition of heart rate

By: HWC, Views: 6750

• Heart rate is determined by the rate of depolarizations of the sinoatrial (SA) node. • Cardiac output is directly proportional to heart rate, the greater the heart rate the greater the cardiac output. • Changes in heart rate are associated with exercise, stress or injury. Nervous ...