B3.3 Biology GCSE Triple Science Flashcards

Vocabulary flashcards for B3.3 Biology GCSE Triple Science.

Homeostasis

The process by which the body maintains a constant internal environment.

Vasoconstriction

Narrowing of blood vessels that supply the extremities, increasing blood flow to vital organs in response to extreme cold.

Hypothermia

A condition where the core body temperature drops below 35°C.

Overheating

When enzymes may denature so body reactions cannot occur, risking death.

Thermoregulatory centre

The part of the brain responsible for regulating body temperature.

Receptor cells in skin

Cells that monitor the external temperature.

Internal receptor cells

Cells that monitor the temperature of the blood.

Effectors

Parts of the body that respond to impulses to return the body to its normal temperature.

Body hairs lower

Hairs on your skin lie flat, preventing an insulating layer of air being trapped around the body.

Sweat glands produce sweat

Glands producing sweat made of water, salt, and urea.

Vasodilation

Blood vessels supplying capillaries near the surface of your skin to widen.

Vasoconstriction

Blood vessels supplying capillaries near the surface of your skin narrow.

Shivering

Muscles contract and relax quickly, making cells respire more quickly, transferring extra energy by heating.

Glucose

An energy store that chemical reactions transfer energy from to ATP.

Insulin

Hormone released by the pancreas when blood sugar levels are too high.

Glycogen

How glucose is stored in the liver, stimulated by insulin.

Type 1 diabetes

People who have this cannot produce insulin because their immune system has destroyed the pancreatic cells that make insulin.

Type 2 diabetes

People who have this cannot effectively use insulin.

Glucagon

Hormone released by the pancreas when blood glucose concentration is too low, making the liver change glycogen back into glucose.

Urea

Toxic substance filtered out of the blood by the kidneys.

Excretion

The removal of waste products.

Lysis

When too much water is present, it will move into your blood cells, causing them to swell and burst.

Urine

A solution containing water, urea, and other waste substances produced by the kidneys.

Selective reabsorption

Process by which the kidneys put back any useful substances into the blood.

Capsule

Outer membrane of the kidney, helping to maintain its shape and protect it from damage.

Cortex

Outer part of the kidney.

Renal Medulla

Inner part of the kidney.

Nephrons

Microscopic tubules inside your kidney where urine is produced containing approximately 1 million in each kidney.

Glomerulus

Knot of capillaries contained in each glomerulus.

Filtrate

Small molecules forced out through the capillary wall into the Bowman's capsule due to increased blood pressure.

Loop of Henlé

The part of the nephron that regulates the amount of salt and water in the body by reabsorbing extra water and salt if needed.

ADH (anti-diuretic hormone)

Hormone secreted from the pituitary gland that makes the walls of the collecting ducts more permeable to water.

Dehydration

Condition when you have not taken enough water into your body.

Hypertonic

Sports drink containing high levels of glucose and salts.

Hypotonic

Sports drink containing low levels of glucose and salts.

Isotonic

Sports drink containing ion concentrations equal to those in blood plasma.

Renal artery

The blood vessel that allows blood to enter the kidney.

Renal vein

The blood vessel that allows blood to leave the kidney.

Ultrafiltration

The process where blood enters the kidney under high pressure, forcing small molecules out through the capillary wall into the Bowman's capsule.

Nephron tubule

The part of the kidney where glucose is absorbed into the bloodstream.

Cells

A low water potential causes water to move into these by osmosis.

Vasoconstriction

The narrowing of blood vessels supplying capillaries near the surface of the skin, reducing heat loss.

Vasodilation

Expansion of blood vessels supplying capillaries near the surface of the skin, increasing heat loss.

Enzyme reactions occur too slowly

The reason metabolic rate slows if body temperature drops.

Thermoregulatory centre

The body system that monitors and controls internal body temperature.

Bloodstream

When glucose is released by digestion, it passes into this.

Pancreas

The organ that releases insulin when blood sugar levels are too high.

Water

The kidney saves this when you are short of water.

Negative feedback system

When ADH production is described as this, it means that the system reverses a change to bring it back to the normal level.

Fluids

An impulse sent to your brain informs you to take on more of these.

Kidney

The renal artery brings blood containing urea and other substances here.

Reduced core body temperature

Causes enzyme reactions to occur too slowly

Sweat glands

Sweat is produced here

Insulin

Type 1 diabetes is controlled by regular injections of this.

Urea

Kidneys filter this out of the blood.

Water vapor

Water is lost from the body as this.

Water is saved

Kidney's save this when you are short of water.

ADH hormone

Hypothalamus detects water potential in blood and secretes this hormone.

Urine

An average person produces up to 900 liters of this per year.

Osmosis

A low water potential causes water to move into blood cells by this.

Glucagon hormone

Liver converts glycogen back into glucose to maintain blood sugar levels, regulated by this hormone.

Loop of Henle

Located in the medulla.

Water

Sports drinks contain essential salts as well as this.