Plant transport + Homeostasis Flashcards
JACK LEIGH IS SO PENG
What do phloem vessels do?
Phloem Vessels transport food materials (mainly sucrose and amino acids) made by the plants from photosynthesis leaves to non-photosynthesising regions in the roots and stem.
What do xylem vessels do?
They transport water and minerals from the roots to the stem and leaves
Name the structural features of the phloem that are different to the xylem
The cells are living cells and are not hollow. Substances move from cell to cell through pores in the end walls of each cell
Name the structural features of the xylem
It is composed of dead cells which form hollow tubes. Xylem cells are strengthened by lignin and so are adapted for the transport of water in the transpiration stream.
Where are the xylem and phloem arranged in a plant to from a plant system and what is it called?
Arranged throughout the root, stem and leaves in groups called vascular bundles
How are the root hair cells adapted?
They increase surface area to volume ratio significantly, they increase the rate of absorption of mineral ions by ACTIVE TRANSPORT
Where do root hair cells grow ?
They grow between soil particles and absorb water and minerals from the soil.
What are root hair cells?
Root Hairs are single-celled extensions of epidermis cells in the root
How is water absorbed by root hair cell?
Water is absorbed by osmosis
Define transpiration
The loss of water vapours from the parts of the plant that are above ground(leaves, stem, flower)
How does transpiration work?
Evaporation of water molecules from the surface of mesophyll cells to air space (water leaves from the stomata)
Describe the process of transpiration
As water evaporated from the leaf, it lowers water potential of cells near the stomata. Water moves from cell to cell by osmosis and evaporates. Water osmoses into the root hair cell from the soil, which osmoses into the xylem. The column of water is pulled up, due to cohesion and back into the leaf.
What variables effect the rate of transpiration
Wind speed, humidity, temperature and light intensity.
What are the two key functions of the urinary system?
- To filter waste products from the blood and expel it as urine
- To control the water levels of the body (osmoregulation)
Name the two blood vessels which connect to the kidney.
Renal artery // Renal vein
Name the tubes which joins the kidneys to the bladder
The ureters
What is the purpose of the urethra in the urinary system
Carries urine from the bladder to outside the body
Name 3 components of urine
Excess water, salts, urea
Name and define the three regions of the kidney
Cortex - the outermost region
Medulla - the inner section of the kidney
Renal pelvis - the tube linking the kidney to the ureter
Where are nephrons found in the kidney
Nephrons are located between the cortex and the medulla
Which part of the nephron is found in the medulla
Loop of Henle
Which structure is found within the Bowman’s capsule
Glomerulus
Explain ultrafiltration
The glomerulus is composed of a knot of small capillaries
This has a small volume so a very high pressure on the blood
The pressure forces out smaller molecules which are known as the filtrate
The substances in the filtrate are glucose, lots of water, urea and salts
Where does the filtrate go in the kidney after being filtered out of the glomerulus
Into the bowman’s capsule, then into the proximal convoluted tube
What occurs in the proximal convoluted tube?
Glucose is reabsorbed into the blood through active transport
What occurs in the loop of Henle?
Salts are reabsorbed by diffusion
Water is reabsorbed by osmosis
This is because the surrounding medulla is salty
The remaining filtrate continues into the distal convoluted tube
What is the role of the collecting duct
Gathers remaining fluid to form urine which then goes to the ureter
