Muscle Physiology Quiz

The process of activating more motor units to increase muscle force. It's like adding more soldiers to your army to increase the strength of your force.

Repeated activation of a muscle fiber before it can fully relax leads to an increase in tension, resulting in a stronger contraction and greater force output. It's like stacking up small pieces of muscle force to create a larger, more powerful force.

Type 1 motor units (slow twitch) are smaller and produce less force compared to Type 2 motor units (fast twitch) which are larger and generate more power. It's like comparing a small car to a large truck.

Activating the stretch reflex in a muscle by slightly stretching it before a contraction helps to increase force output. It's like pre-stretching a rubber band before launching it.

As the speed of a muscle contraction increases, the force it generates generally decreases. It's like a car - the faster you drive, the less weight you can haul.

Muscle action that produces force without changing length. It's like pushing against a wall - you're using muscle force, but not moving.

Muscle action that produces force with length changes. It's like lifting weights - you're using muscle force and changing the length of the muscle.

Concentric contractions shorten the muscle while producing force (lifting a weight), while eccentric contractions lengthen the muscle while producing force (lowering a weight). It's like pushing against a door opening or closing it.

A nerve or muscle fiber will either completely respond to a stimulus or not at all, regardless of its strength or duration.

The addition of tension in a muscle during repeated stimulation, leading to a stronger contraction.

Sensory receptors located within muscles that detect changes in muscle length and initiate the stretch reflex.

Sensory receptors located within tendons that detect changes in muscle tension and act as a protective mechanism against excessive force.

An involuntary muscle contraction in response to a rapid stretch, triggered by muscle spindles.

A muscle contraction where muscle length remains constant, generating force without movement.

A muscle contraction where the muscle lengthens while generating force, often stronger than concentric contractions.

The volume of oxygen consumed by the body during exercise. It reflects the rate at which your body is using oxygen.

The maximum amount of oxygen a person can utilize during strenuous physical activity. A higher VO2max indicates better aerobic fitness.

The difference in oxygen content between arterial blood (oxygenated blood) and venous blood (deoxygenated blood) during exercise. Reflects the amount of oxygen extracted by the working muscles.

The number of mitochondria per unit of muscle tissue. Mitochondria are the powerhouses of the cells, responsible for energy production.

The number of capillaries per unit of muscle tissue. Capillaries are tiny blood vessels that deliver oxygen and nutrients to the muscles.

The process of converting genetic information encoded in DNA into messenger RNA (mRNA).

The process of using mRNA to create a protein chain. This happens in the cytoplasm.

A brain region that controls many physiological processes, including the release of growth hormone.

A hormone that stimulates growth and muscle development.

A group of hormones that regulate various physiological processes, including the fight-or-flight response. They play a key role in the acute responses to exercise.

A sequence of movements involving an eccentric phase (muscle lengthening), an amortization phase (brief pause), and a concentric phase (muscle shortening) that utilizes elastic energy stored in tendons for powerful muscle contractions.

The brief transition period between the eccentric and concentric phases of the SSC, where the muscle is briefly paused to allow for maximum energy transfer from the stretched tendons to the muscle.

A three-phase physiological response to stress, encompassing an alarm phase (initial stress), a resistance phase (adaptation), and an exhaustion phase (overtraining).

The principle of gradually increasing the demands placed on the body during training to promote adaptation and improvement.

Changes in the nervous system that occur in response to resistance training, leading to increased muscle strength and power.

The increase in size and volume of muscle fibers, primarily due to increased protein synthesis and enhanced myofibril density.

Insulin lowers blood glucose levels by promoting glucose uptake by cells, glycogen synthesis in the liver and muscle, and inhibiting glucose production by the liver.

Glucagon raises blood glucose levels by stimulating glycogen breakdown in the liver, gluconeogenesis, and inhibiting glucose uptake by cells.

Activating the AMPK pathway during exercise improves insulin sensitivity, increases glucose uptake by muscles, and promotes fat burning, which could help manage blood sugar levels in Type 2 diabetics.

Steroid hormones, like testosterone, enter the cell and bind to a receptor, which then binds to DNA and initiates the transcription of mRNA.

The mRNA produced by transcription leaves the nucleus and is translated by ribosomes to create a protein.

Growth hormone binds to its receptor, activating JAK, which then phosphorylates STAT.

Two phosphorylated STAT molecules form a dimer, which enters the nucleus and activates gene transcription, resulting in the production of new proteins.

Growth hormone (GH) is released from the pituitary gland. Factors stimulating GH release include exercise, sleep, and low blood glucose levels.

Activation of beta receptors in the body leads to various physiological responses, including bronchodilation (relaxation of airways) and increased sweat production in working muscles.

The fluctuations in hormone secretion levels throughout the day. These changes can be influenced by factors like sleep-wake cycles, meal times, and stress levels.

Located on the cell surface, these receptors bind to peptide hormones triggering a signal cascade that leads to intracellular changes.

Located inside the cell, these receptors bind to steroid hormones, influencing gene expression and protein synthesis.

A chain reaction within a cell triggered by a signal from outside (like a peptide hormone). This system amplifies the initial signal and produces a specific cellular response.

These stress hormones increase during exercise due to the activation of the sympathetic nervous system, preparing the body for 'fight or flight' by increasing heart rate.

Growth hormone (GH) stimulates the release of IGF-1 (Insulin-like Growth Factor 1) which helps regulate GH's effects and promotes fat metabolism.

Epinephrine utilizes cyclic AMP (cAMP) as a second messenger to activate a pathway that breaks down fat stores for energy production.