B3 Quiz

Osmosis is the movement of across a from an area of high concentration to an area of low concentration.

In root hair cells, the concentration of minerals is usually higher in the cell than in the soil surrounding it. Active transport allows the plant to absorb minerals from a very dilute solution. This is essential for the plant

When there's a higher concentration of glucose and amino acids in the gut they diffuse naturally . If there is a lower concentration of nutrients in the than in the , active transport is necessary to

The alveoli are small air sacs inside your . Inside them, gas exchange takes place wherein is transferred to the blood and is removed. They are adapted for efficient diffusion as they have a large , moist , walls and good supply.

The small intestine is covered in millions of projections called . They increase the small intestine's in order to speed up . The have a layer of surface cells so there isn't long for food to diffuse through, and a good for quick absorption.

The transpiration stream happens through vessels when there is a shortage in a plant and it is therefore necessary for these vessels to replace it.

How does the heart work?

Blood flows into the from the and the .
The contract which pushes blood into the .
The contract which forces blood into the and the and out of the .
Blood flows to organs through .
Blood returns to the heart through .
The fill again and the cycle repeats.

Artificial blood is often used in situations wherein a patient is a lot of blood. It buys the patient time to produce new so the heart can continue pumping. It is relatively safe, as long as there are no present in the artificial blood.

are tubes inserted into the arteries to keep blocked arteries open so can pass through and the heart can continue beating. They are used to prevent heart attacks in people with disease (fatty deposits blocking arteries) however if forms due to stent irritation, the artery can narrow again. Drugs are needed to prevent .

Homeostasis is the maintenance of .

Your kidneys regulate the water content in your body. Water is taken in by and , and lost in , and the air we breathe out. On a cold day you don't sweat so you produce urine which is and . On a hot day you do sweat so you produce urine which is and .

Your kidneys regulate the ion content in your body. Ions are taken in in and absorbed into the . If there is an incorrect balance of water and ions in your body, the wrong amount of water will be drawn into your cells by which can your cells or make them not work as well. Your kidneys remove excess sodium from the . Some ions are lost in .

Your kidneys remove urea from your body. Urea is produced as a waste product in the reaction of being converted to and to be stored. This reaction takes place in the . Urea is poisonous. The first releases it into the , then the kidneys filter out the and temporarily store it in the in urine to be excreted from the body.

are the filtration units in the kidneys.

The kidneys act as a filter in three stages. These are , and the .

During filtration, a high pressure squeezes water, , and sugar out of the blood and into the . molecules cannot get through so proteins and blood cells stay in the blood.

During reabsorption, substances are reabsorbed into the blood. These include all and sufficient (both by ), as well as sufficient .

During the release of wastes in the kidneys, substances (including ) continue out the nephron, into the ureter and down to the bladder as .

Dialysis is one way to treat kidney failure. The person's blood flows along a barrier surrounded by dialysis fluid. It acts like the in the kidneys by being permeable to things like and waste substances, but not allowing molecules through. Dissolved ions and glucose aren't lost from the blood during dialysis because the dialysis fluid has the concentration of them as healthy blood. Waste substances and excess ions/water can across the barrier. Although this saves lives, it's a hassle as patients go three times a week for hours. Dialysis can cause or infections.

A kidney transplant will kidney failure. A donor who has died suddenly or is on the organ donor register gives a healthy kidney to a patient with kidney failure. The donor kidney could be by the patient's immune system as the patient's attack the donor kidney's foreign . This can be prevented if the donor's tissue type the patient's tissue type, or if the patient takes . These make them susceptible to illness. Dialysis necessary with a kidney transplant.

Type 1 Diabetes is caused when the pancreas doesn't produce enough so blood glucose levels can to a deathly level.