Heart + lungs Flashcards
(20 cards)
A person’s heart stops beating. The person stops breathing. A first-aider pushes down on the person’s chest. Pushing down on the person’s chest puts pressure on the heart. 0 1 . 2 Explain why putting pressure on the heart helps the person.
it simulates the heart’s pumping action, forcing blood to circulate throughout the body, delivering oxygen to vital organs like the brain, even when their heart has stopped beating
The first-aider also forces air into the person’s lungs by blowing into their mouth. Describe how forcing air into the person’s lungs helps the person.
helps supply them with oxygen
The pancreas produces several digestive enzymes. CF reduces the amount of each enzyme that reaches the small intestine. Explain why a person with CF has: * difficulty digesting food * difficulty gaining body mass.
the thick, sticky mucus produced by their condition blocks the ducts in the pancreas, preventing the digestive enzymes from reaching the small intestine, which means their bodies cannot properly break down and absorb nutrients from food, leading to malabsorption and poor weight gain
Gas exchange happens in the alveoli in the lungs. Describe three features of the alveoli that help maximise gas exchange.
large surface area - significant amount of oxygen can diffuse from the alveoli into the blood and carbon dioxide can diffuse from the blood into the alveoli
thin walls - minimises distance that the gasses have to diffuse through
rich blood supply - ensures that the blood in the capillaries is constantly being replenished with fresh oxygen
CF reduces the amount of oxygen that can enter the blood from the alveoli. Explain how a reduced amount of oxygen entering the blood will affect the human body.
decrease in blood oxygen levels , which impacts various bodily functions
fatigue, difficulty breathing, rapid heart rate
Test for Starch
Add iodine solution to the food sample.
If starch is present, the solution will turn blue-black.
If no starch, the solution stays orange-brown.
Test for Reducing Sugars
Add Benedict’s solution to the sample.
Heat in a water bath at around 75°C for 5 minutes.
If sugar is present, the solution changes from blue → green → yellow → brick-red depending on concentration.
Test for Protein
Add Biuret solution to the food sample.
If protein is present, the solution will turn purple.
If no protein, it stays blue.
Test for Lipids (Fats)
Ethanol emulsion test.
For ethanol test:
Add ethanol and shake.
Add water and shake again.
A milky white emulsion means lipids are present.
Describe the chemical tests that could be used to show the presence of the two types of carbohydrate in cake. Include a risk assessment in your answer.
Starch Test:
Mash or blend a small amount of the cake and mix it with water to make a solution.
Add a few drops of iodine solution.
If starch is present, the solution will turn blue-black.
If no starch, it will stay orange-brown.
Reducing Sugar Test (e.g. glucose):
Place a small amount of the cake mixture into a test tube.
Add Benedict’s solution.
Heat the test tube in a water bath at about 75°C for 5 minutes.
If reducing sugars are present, the solution will change from blue to green, yellow, or brick-red depending on how much sugar is present.
Risk Assessment:
Wear safety goggles to protect eyes from splashes.
Take care with hot water baths to avoid burns — use tongs or heat-resistant gloves.
Iodine and Benedict’s solutions are irritants — avoid contact with skin and wash hands after use.
Clean up spills and dispose of solutions safely
Osmosis in Plant Tissue
Cut 6 pieces of potato. Measure them so they have the same initial mass. Put each of them in a different salt solution concentration: 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0. Keep all of them in there for 2 hours. Then remove them and pat them dry with a paper towel to remove the excess water. Measure the new mass and calculate the mass change. Repeat and calculate a mean. Plot on a graph
A student placed antibiotic discs on a bacteria-covered agar plate. One of the antibiotics produced a clear area around it. What does this show?
It had a zone of inhibition around it where bacteria are not growing so it killed some bacteria
Explain how sub-cellular structures help to move dissolved sugars into the phloem
The concentration of ions in cell X is lower than the phloem. Therefore, the ions move from an area of low concentration to high concentration through active transport against the concentration gradient which is an active transport which requires energy released by aerobic respiration. Therefore, Cell X has many mitochondria for aerobic respiration
The leaf tissue that contains the most chloroplasts is
The leaf tissue that contains many air spaces is the
The plant tissue that can differentiate throughout the life of the plant is the
Palisade mesophyll. Spongy mesophyll. Meristem.
Substance that strengthens xylem tissue
Lignin
Explain the result for the potato pieces in the 0.6 mol/dm3 salt concentration.
The concentration inside the potato was higher than the concentration outside the potato. Therefore water moved out of the potato from a dilute to a concentrated solution through a partially permeable membrane through osmosis, so the mass of the potato decreased.
Explain why the result for the potato pieces at 1.0 mol/dm3 was different from the result at 0.6 mol/dm3.
It had a steeper concentration gradient so more water moved out, so more mass was lost
Give the scientific term that describes the yellow colour of the leaves.
Chlorosis
The rate of photosynthesis is affected by different factors. How could the oxygen produced during photosynthesis be used to measure the rate of photosynthesis?
Measure the volume of oxygen produced per minute
