Movement Of Substances Flashcards
Explain how a root hair cell carries out its function
-Mineral ions are taken up by active transport
-The water potential inside the root hair cell decreases
-Water enters the root hair cell by osmosis
Describe two effects that the accumulation of waste products would have on cells. (2)
-Waste products would be toxic to cells/would denature enzymes
-Waste products would cause water to move out of cells by osmosis
-Waste products would take up storage space inside cells
What are the excretory products of the lungs?
-Lung excreted carbon dioxide
-as a waste product of aerobic respiration via exhalation
What are the excretory products of the kidney?
-Kidney excretes excess water, salts and urea
-by producing urine via osmoregulation
What are the excretory products of the skin?
-Skin excretes excess water and salts
-Through sweat glands of skin by producing sweat
What are the two main functions of the kidney?
-They regulate the water content of the blood (vital for maintaining blood pressure)
-They excrete the toxic waste products of metabolism (such as urea) and substances in excess of requirements (such as salts)
How does the kidney carry out its roles of excretion?
- Renal Artery carries oxygenated blood to Glomerulus in Bowman’s Capsule at high pressure
- High pressure due to wider afferent arteriole and narrow efferent arteriole
- Blood filtered at high pressure produces Glomerular Filtrate: water, glucose, salts, urea
- Proteins and red blood cells too large to filter through base membrane, remain in blood
- Glomerular Filtrate enters Proximal Convoluted Tubule (PCT), where glucose selectively reabsorbed
- Remaining filtrate moves to Collecting Duct, where water reabsorbed based on ADH levels
- Excess water, salts, and urea form urine
- Urine transported via ureter to bladder for storage and excretion
What are the key functions of the urinary system?
-Filter and remove waste products
-Control water levels
Describe the structure of the Bowman’s capsule
- Cup-shaped sac collects Glomerular Filtrate
- Filtrate enters tubules for filtration
Describe the structure of the glomerulus
- Tuft of capillaries filters blood under high pressure
- Produces Glomerular Filtrate: water, glucose, salts, urea
Describe the structure of the convoluted tubules
- Nephron section: Proximal Convoluted Tubule (PCT) and Distal Convoluted Tubule (DCT)
- Purpose: Selective reabsorption of glucose into blood capillaries
Describe the structure of the loop of Henle
- U-shaped nephron section regulates body water concentration
- Filters out salts for homeostasis
Describe the structure of the collecting duct
- Long, narrow tube
- Reabsorbs water
- Maintains water balance
- ADH levels regulate process
Describe the process taking place in the glomerulus (2)
-Small molecules are forced out of the capillaries (of the glomerulus) into the Bowman’s capsule
-Due to the high pressure in the capillaries (of the glomerulus)
-During the process of ultrafiltration
Ultrafiltration
-Occurs between the glomerulus and Bowman’s capsule
-High pressure created by: blood from renal artery, narrowing of capillaries in glomerulus
-Filtrate is formed when small molecules are forced into the Bowman’s capsule