A1.2 - A.1.3

Question 1

homeostasis

Answer 1

the condition in which the body’s internal environment remains relatively constant.

Question 2

what can extreme temps do for sports

Answer 2

can limit performance, increase the risk of heat illness or cold injury, and can pose life-threatening situations.

Question 3

Stressors

Answer 3

come from within the body (e.g low blood glucose levels) or outside the body (e.g intense cold, low oxygen etc).

Question 4

overall What is the hypothalamus responsible for

Answer 4

maintaining homeostasis by regulating most processes that affect the body’s internal environment

Question 5

What does a negative feedback mechanism include

Answer 5

A receptor (such as nerve endings in the skin that sense temperature)
A control center (such as the hypothalamus)
An effector (such as shivering if your body temperature drops)

Question 5

Intrinsic

Answer 5

internal (regulation of the heart by the heart it takes care of itself)

Question 6

What is the hypothalamus more specifcally responsible for that are the bodies processes effecting its internal enviroment

Answer 6

Blood pressure
Heart rate
Strength of contraction of the heart
Respiration
Digestion
Body temperature
Thirst and fluid balance
Interaction between the nervous and endocrine systems
Appetite and food intake
Sleep-wake cycles

Question 7

What do negative feedback loops work to do

Answer 7

they work to reverse the effects of the stimulus and return the body to a state of homeostasis (like making the body warmer when its really cold)

Question 7

The sinoatrial (SA) node

Answer 7

generates electrical impulse and Causes contraction of atria then stimulation of AV node

Question 8

explain the negative feedback loop of the regulation of ph in the blood

Answer 8

To maintain homeostasis, the respiratory control center in the brain and chemoreceptors throughout the body monitor the blood acidity. If CO2 levels rise and the blood becomes acidic (this can harm organs and is more common in exercise), the respiratory control center increases the rate and depth of breathing which speeds up the removal of CO2 from the blood and body, returning the blood to it’s normal ph levels.

Question 9

The atrioventricular (AV) node

Answer 9

generates secondary impulse and
Causes contraction of ventricles

Question 10

regulation/negative feedback loop of the heart in excersise

Answer 10

when exercise begins, the sympathetic nervous system stimulation increases to have the heart beat faster and more powerfully to supply the required blood and oxygen to working muscles.

in general controlled by the autonomic nervous system which uses the sympathetic nervous system to increase heart rate and force of contraction and the parasympathetic nervous system to slow it down and do the opposite

Question 11

regulation of blood glucose

Answer 11

When blood glucose levels are high (e.g after a meal), the pancreas releases insulin into the bloodstream
Insulin signals the liver and muscle cells to take up glucose and convert it into glycogen for storage and stimulates the adipose tissue to take up the glucose and store it as fat

When blood glucose levels are low (during exercise or fasting), the pancreas releases glucagon
Glucagon signals the liver to break down glycogen into glucose and release it into the bloodstream, raising blood glucose levels
The endocrine and energy systems work together to maintain appropriate blood glucose levels by using hormones to regulate glucose metabolism in the body

Answer 12

During exercise lasting >30 min, insulin levels drop but even though there is less insulin in the blood, the insulin that is there in excersise is more effective at allowing the glucose into the muscle and liver cells.

Question 13

what can happen to insulin sensitivity with increased exercise

Answer 13

exercise also increases insulin sensitivity so the body needs less insulin to transport glucose over time. This effect occurs because muscle contractions stimulate glucose transport proteins to move to the cell surface, allowing glucose to enter the cell directly.

Question 14

what is insulin resistance

Answer 14

Insulin resistance is when the body’s cells become less sensitive to insulin and do not uptake the glucose from the blood, leaving blood sugar levels high. This can lead to serious health problems including Type II Diabetes.

Insulin resistance results in the pancreas producing MORE insulin to regulate the blood sugar levels and, over time, the body becomes less sensitive to it.

Question 15

metabolic rate

Answer 15

The amount of energy required to complete regular, daily activities

Question 16

what factors effect metabolic rate

Answer 16

Exercise (↑ metabolic rate)
Hormones (thyroid hormone ↑ metabolic rate)
Nervous System (SNS activity ↑ metabolic rate)
Body temperature (higher body temp ↑ metabolic rate)
Ingestion of food (↑ metabolic rate)
Age (children have higher metabolic rate than adults)
Sex differences (metabolic rate is lower in biological females, except during pregnancy)

Question 17

heat gradient

Answer 17

heat being transferred from a hot area to an area not as hot as where its being transferred from. Like climbing down the ladder.

Question 18

Conduction

Answer 18

A heat transfer method that involves direct contact between surfaces and depends on the heat gradient e.g running on a hot track

Question 19

Convection

Answer 19

moving heat from one place to another via air or water e.g the human body loses heat to water if the water is cooler, body loses heat to the environment if the air is cooler than the body

Question 20

Radiation

Answer 20

energy waves that are sent from the sun and are absorbed by the body e.g sunbathing when the air is warmer than the body

Question 21

how does humidity affect evaporation

Answer 21

maximal evaporative cooling is affected by the humidity (amount of water particles in the air). If the air is already laden with moisture, there is no gradient for the sweat to evaporate into as the air is already moist. The sweat just rolls off the skin and provides no cooling effect at all and more acts as a warm blanket.

Question 21

how does Evaporation work in maintaining homeostasis and sports in general

Answer 21

The body detects that there is an increase in core body temperature and vasodilates the blood vessels which allows more blood (and heat) to flow to the peripheries and skin to lower the core temperature and be evaporated and release that heat.

Question 22

What are Three factors influence the total amount of sweat vaporized from the skin

Answer 22

SURFACES EXPOSED TO THE ENVIRONMENT - the more exposed, the more sweat is produced HUMIDITY - more humidity less evaporation TEMPERATURE - sweat rates increase with increasing temperatures

Question 23

how does the body maintain homeostasis when its really cold

Answer 23

- The SNS stimulates increased metabolism, increased metabolism produces heat. - brown fat is activated which increases heat, uses glucose. Shivering - the body starts to shiver in response to cold, which uses muscular contractions to generate heat. Vasodilation - the widening of the blood vessels to allow more heat to be transported to the peripheries Vasoconstriction - the narrowing of the blood vessels to keep the heat closer to the core and maintain body temperature during the cold

Question 24

What sex has a higher sweat rate

Answer 24

males so they can disapate heat quicker

Question 25

who has a higher surface mass ratio

Answer 25

females normally have a higher surface mass ratio which can be better for better heat dissipation, especially in endurance events. But it can be a disadvantage as the body will absorb more of the heat from the environment due to the larger surface area leading to the body being unable to stay cool enough to perform well

Question 26

How does hormonal fluctuation affect thermoregulation

Answer 26

Increased progesterone in the luteal phase causes delayed onset of sweating, which decreases skin blood flow and a small increase in internal body temperatures - none of which are good when trying to keep cool.

Question 27

Higher S/M Ratio (small body size, lean build) in thermoregulation

Answer 27

More surface area relative to mass → Faster heat exchange. Greater heat loss in cold environments → Harder to retain body heat. Better heat dissipation in hot environments → Advantageous in warm climates.

Question 28

Lower S/M Ratio (large body size, broad thick build)

Answer 28

Less surface area relative to mass → Slower heat exchange. More heat retention in cold environments → Helps conserve warmth. Reduced heat loss in hot environments → Higher risk of overheating.

Question 29

Advantages and disadvantages for a women in a hot dry climate

Answer 29

Advantage: Producing less sweat per gland may help reduce overall water loss, so less dehydration. Less sweat also means the body retains more fluids, which could help sustain endurance Disadvantage: in a hot, dry environment, where sweat can evaporate quickly to cool the body efficiently, producing less sweat might limit cooling potential. This could lead to higher core temperatures compared to those who sweat more, increasing the risk of overheating.

Question 30

Advantages and disadvantages for a female in hot humid climates

Answer 30

Advantage: sweat evaporation is limited due to the high moisture content in the air. Because the cooling effect is reduced, producing less sweat per gland can help prevent excessive water loss without sacrificing much in terms of effective cooling. This could be beneficial for managing hydration levels Disadvantage: less sweat production may still make it harder to maintain a stable body temperature, increasing the risk of overheating in prolonged, intense activities.

Question 31

process of breathing

Answer 31

Air is initially breathed in through the nose and mouth and it is warmed and moistened. It continues through the larger airways such as the trachea and bronchi. The bronchi continue to get smaller and branch into bronchioles which then end in alveoli. Alveoli are 1 cell thick and this is where gas exchange takes place with oxygen and carbon dioxide moving across the very thin barrier that separates the alveoli from the passing blood for further transport.

Question 32

what pressure needs to occur for inhalation

Answer 32

he pressure inside the lungs needs to be less than the pressure in the atmosphere. The diaphragm contracts and pulls downwards, which makes the thoracic cavity larger and decreases the pressure, causing air to flow into the lungs along the pressure gradient.

Question 33

what pressure needs to occur for exhalation

Answer 33

In exhalation at rest, the breathing out process is passive, the diaphragm relaxes and recoils back to its original position, making the thoracic cavity smaller and increasing the pressure, causing air to flow back out again.

Question 34

in exercise how is respiration maximized

Answer 34

More muscles including the intercostals, abdomen and even shoulders contribute by increasing the lung volume during inhalation. Contraction of these same muscles during exhalation, compresses the lungs faster and more forcefully to expel more air.

Question 35

Vital Capacity

Answer 35

volume of air forced out after maximum inhalation; the sum of ERV, VT, and IRV.

Question 36

Expiratory Reserve Volume

Answer 36

the amount of air you can breathe out above a normal breath

Question 36

Tidal Volume

Answer 36

the volume of air moving in and out of the lungs during regular breathing

Question 37

Inspiratory Reserve Volume

Answer 37

the amount of air you can breath in above a normal breath

Question 38

Residual Volume

Answer 38

the amount of air left in the lungs after maximal breathing out

Question 39

Total Lung Capacity

Answer 39

maximal volume of gas in the lungs after a maximal inhalation; the sum of the RV, ERV, VT, and IRV. NOT INCLUDING the amount of air in the lungs thats always there just incase

Question 40

How can lung volume change

Answer 40

Lung volume increases with age, Biological females have typically lower lung volume and capacity compared to males Vital capacity is generally higher in taller people than short people

Question 40

concentration gradient

Answer 40

Gas will move from an area of concentration to an area of lower concentration

Question 41

how does concentration gradient work in the body

Answer 41

In the lungs, the air breathed in is high in oxygen and low in carbon dioxide. The blood coming back to the lungs from the tissues is low in oxygen and high in carbon dioxide. Therefore, the oxygen will diffuse from the alveoli to the capillaries and be pumped to the tissues via the heart. The carbon dioxide will diffuse into the alveoli and be breathed out.

Question 42

Minute Ventilation

Answer 42

amount of air being expelled in 1 minute. determined by the amount of air breathed in in one breath (tidal volume) multiplied by the number of breaths per minute/ respiration rate

Question 43

Primary function of the blood

Answer 43

to transfer gasses, nutrients, waste products, hormones and heat to and from various tissues.

Question 44

Components of blood

Answer 44

Plasma - Mixture of water and electrolytes and transports Platelets - assist in clotting White Blood Cells - involved in immune function Red Blood Cells - carry oxygen to tissues and carbon dioxide back to the lungs for exhalation

Question 45

what is hemoglobin responsible for

Answer 45

Carrying oxygen and delivering to tissues its also rich in iron

Question 46

how does altitude training work

Answer 46

If haemoglobin concentration can be increased, more oxygen can be transported and aerobic performance will improve. In altitude training, an athlete lives and/or trains at high altitudes (where oxygen availability is lower) and the body naturally adapts by producing more haemoglobin and they perform better when they return to sea level with more oxygen availability .

Question 47

What is blood doping

Answer 47

its an illegal way, where athletes inject previously extracted blood back into their bodies which allows more oxygen to be transported and improves performance. So the red blood cells are put back into them carrying a lot of hemoglobin boosting there oxygen transportation.

Question 48

Arteries

Answer 48

large diameter, thick muscular walls there is significant pressure as the oxygen rich blood is pumped around the body. They are responsible for taking oxygenated blood to the tissues away from the heart.

Question 49

Capillaries

Answer 49

narrow vessels with very thin walls. They are the sites of exchange between blood vessels and tissues.

Question 50

Veins

Answer 50

Veins are responsible for delivering deoxygenated blood back to the heart. They are less muscular as pressure is lower and have valves to stop backflow.

Question 51

Pulmonary circulation

Answer 51

delivers deoxygenated blood from the right side of the heart to the lungs for reoxygenation and then back to the left side of the heart to be pumped around the body.

Question 52

Systemic circulation

Answer 52

delivers oxygenated blood from the left side of the heart to body tissues where the oxygen is used up. It then takes deoxygenated blood back to the right side of the heart to continue the cycle

Question 53

how is blood pressure measured

Answer 53

pressure of the walls of the artery

Question 53

how does blood travel around the heart

Answer 53

Atrium receives blood first, then pushes it into a larger and thicker walled ventricle. From the ventricle, it is ejected out of the heart.

Question 54

Systolic Blood Pressure

Answer 54

the pressure during the contraction of the ventricles

Question 55

Diastolic blood pressure

Answer 55

pressure during the relaxation of the ventricles

Question 56

normal blood rpessure

Answer 56

around 120/80

Question 57

what does static and dynamic excersise do for blood pressure

Answer 57

causes increase in stysolic and dyolic blood pressure due to sustained muscle contractions. over time static excersise and dynamic excersise can lead to a lower resting blood pressure

Question 58

Why is high blood pressure bad

Answer 58

It puts extra strain pon the heart and blood vessels which can create damage overtime, leading to heart disease, stroke, kidney disease, and eye damge

Question 59

Cardiac output

Answer 59

The amount of blood ejected from the heart in liters per minute. Cardiac output = stroke volume x heart rate

Question 60

cardiac drift

Answer 60

Over time, heart rate increases to maintain this output due to stroke volume decreasing due to sweating and therefore less blood coming back to the heart.

Question 61

Stroke Volum

Answer 61

amount of blood being ejected with each contraction (in milliliters/mi)

Question 62

Maximal Oxygen Uptake (VO2 Max)

Answer 62

maximum rate at which an individual can take in and use oxygen.

Question 63

nonshivering Thermogenesis

Answer 63

Nonshivering thermogenesis is heat production through metabolic activity, primarily in brown adipose tissue (BAT). It occurs when the body releases norepinephrine, stimulating mitochondria in BAT to generate heat instead of ATP. This is common in infants and hibernating animals but also occurs in adults to a lesser extent.