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BIOLOGY Flashcards

1
Q

Name 3 difference between INFECTIOUS and NON-INFECTIOUS diseases

A
  1. ID: Spread from one person to another
    NID: Cannot be spread from one person to another
  2. ID: Caused by pathogens
    NID: Not caused by pathogens
  3. ID: Not Inherited
    NID: May be inherited
    (NID: Or may be caused by factors like air pollution, malnutrition, lifestyle choices)
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2
Q

Name 3 examples of INFECTIOUS and NON-INFECTIOUS DISEASES

A

Infectious: Influenza, HIV, Pneumococcal disease

Non Infectious: Type 2 diabetes, Liver cirrohsis, Coronary Heart disease

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3
Q

What is a disease?

A

A condition that causes the body to function less effectively.

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4
Q

What are 3 ways Infectious Diseases are spread?

A
  1. Through Droplets in the Air
  2. By Direct Contact (exchanging bodily fluids)
  3. By contaminted Food and Water
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5
Q

What are substances that can trigger the PRODUCTION OF ANTIBODIES?

A

Antigens

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6
Q

How do vaccines work?

A

A vaccine, which contains an agent that resembles a pathogen (antigen), introduces virus to the body, it stimulates the WBC to quickly reproduce antibodies to destroy them, and recognise in future.

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7
Q

What is used to kill BACTERIA CELL and VIRUS?

A

Bacteria - Antibiotics
Virus - Vaccine

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8
Q

What are examples of antigens?

A

-PROTEINS on the surface of pathogens, such as bacteria and viruses, are examples of antigens.

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9
Q

What are antibiotics?

A

Drugs used to treat bacterial infections. made by MICROORGANISMS and are used to kill or inhibit the growth of bacteria.

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10
Q

Why do Antibiotics kill Bacteria but not VIruses?

A

Antibiotics are INEFFECTIVE against them because viruses DON’T have CELL WALLS, CELL MEMBRANES, or RIBOSOMES.

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11
Q

How do Antibiotics work?

A
  1. Weakening the bacterial cell wall, thus allowing water to enter the bacterial cell by osmosis and causing it to swell and burst.
  2. Preventing ribosomes from making proteins and enzymes, thereby killing the bacteria.
  3. Breaking up bacterial cell membranes.
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12
Q

What are antivirals?

A

Medications that help the body fight off disease-causing viruses.

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13
Q

What are superbugs?

A

Bacteria resistant to antibiotics

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14
Q

How can we reduce ANTIBIOTIC RESISTANCE in Bacteria?

A
  1. Not MISUSING or OVERUSING antibiotics.
  2. Completing the full course of antibiotics prescribed by doctors
    (so that all bacteria is killed).
  3. Using antiobiotics only when neccesarry.
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15
Q

What are INFECTIOUS DISEASES caused by?

A

These diseases are caused byPATHOGENS (include viruses, bacteria, fungi and parasites).

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16
Q

What are the ‘5 F.I.G.H.T. steps’ to prevent the spread of diseases?

A

Frequent handwashing

Immunisation

Go to the doctor

Home rest

Tissues and masks

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17
Q

Whar are the 3 main components tobacco smoke and its HARMFUL EFFECTS on the body?

A

[CARBON MONOXIDE]
-Reduces ability of blood to carry oxygen
-Increases risk of Coronary Heart disease

[NICOTINE]
-Causes addiction
-Increases heart Rate and Blood Pressure
-Increases risk of Coronary Heart disease

[TAR]
-Paralyses the cilia lining the air passage
-Increases risk of bronchitis and emphysema
-Increases risk of lung cancer

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18
Q

[TRUE / FALSE]
‘Carbon monoxide will bind with haemoglobin to form carboxyhaemoglobin. This will reduce the ability of red blood cells in transporting oxygen to the body cells.’
EYA

A

TRUE.
-Normally oxygen binds to haemoglobin to form oxyhaemoglobin.

-However haemoglobin has a higher affinity for carbon monoxide and binds with it more readily.

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19
Q

Name a chemical present in tobacco smoke and explain how it could have caused lung cancer.

A

Tar present in tobacco smoke. Tar is carcinogenic. It causes cells in the lung tissue to multiply uncontrollably and grow into a tumor.

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20
Q

How does the CANCEROUS TUMOR affect LUNG FUNCTION?

A

The tumor is a mass of tissue that occupy the air spaces and destroy the alveoli.
This will decrease the surface area for gas exchange.
Less oxygen will be absorbed into the blood stream and less carbon dioxide will be removed.

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21
Q

What are the possible treatment(s) for lung cancer?

A

(a) Chemotherapy/ radiotherapy to kill the cancer cells.

(b) Removal of the tumor from the lung hence person will lose part of the lung.

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22
Q

State the difference between a TISSUE and an ORGAN

A

A tissue is made up of similar cells but an organ is made up of different tissues.

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23
Q

State the difference between an organ and an organ system.

A

An Organ is made up of different tissues but an organ is made up of different organs.

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24
Q

What is the function of the:
-Red Blood Cell
-Nerve Cell
-Muscle Cell
-Cultured Stem Cell
-Root Hair Cell

A

Red Blood Cell- Carry oxygen from our lungs to the rest of the body

Nerve Cell- Sends commands to the brain and gives signals.

Muscle Cell- Perform movement for the body.

Cultured Stem Cell- Repair system for the body.

Root Hair Cell- Allows the plant to absorb more water.

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25
Q

What is the function of Mitochondria and Chloroplast?

A

MITOCHONDRIA - Sites of respiration and provides energy.
CHLOROPLAST - Sites of photosynthesis and produce glucose and oxygen.

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26
Q

State DIFFERENCES and SIMILARITIES between animal and plant cells.

A

DIFFERENCE
[No/Cell Wall]
-This protects plant cells against mechanical (physical injury) and retains a fixed shape.

[Small/Large Central Vacuole]
-This enables plant cells in providing STRUCTURAL SUPPORT by providing turgidity.

[No/Chloroplast]
-This enables plant cells to photosynthesize and manufacture food and oxygen to allow for respiration.

SIMILARITIES:
Nucleus, Cell Membrane, Cytoplasm, Ribosome, Mitochondria.

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27
Q

(3) What is the structure and function of the RED BLOOD CELL?

A

[Structure]
1. Has haemoglobin
2. No nucleus
3. Biconcave

[Function]
1. Carry oxygen
2. Can carry more haemoglobin, thus transporting more oxygen.
3. Higher SA to VR for faster DIFFUSION of oxygen IN and OUT of the cell.

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28
Q

(2) What is the structure and function of the ROOT HAIR CELL?

A

[Structure]
1. Long, Narrow Protrusion
2. Concentrated Sap Vacuole (due to the mineral salts entering RHC against its concentrate using energy, thus, it also has a lot of mitochondria)

[Function]
1. Higher SA to VR for faster ENTRY of water by osmosis & mineral salts by diffusion.
2. Maintains water potential gradient for water to be removed by osmosis.

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29
Q

What is diffusion?

A

Net movement of particles from a region of high concentration to a region of low concentration, down the concentration gradient until equilibrium is reached.

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30
Q

What is osmosis?

A

Net movement of water molecules from a region of higher water potential to a region of lower water potential through a partially permeable membrane.

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31
Q

Explain the effects of osmosis when water moves IN plant cell.

A

Description:
-Water went in
-Larger, Turgid (doesn’t burst because of cell wall)

Explanation:
1. The solution has a higher water potential than the cell.
2. Water movies IN by osmosis.
3. Cells become larger and are turgid.
4. Water molecules move down a water potential gradient.

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32
Q

Explain the effects of osmosis when water moves OUT of plant cells.

A

Description:
-Water went out
-Smaller, flaccid (soft), then plasmolysed.

Explanation:
1. The cell has a higher water potential than the solution.
2. Water moves OUT of the cell by osmosis.
3. Cell shrinks, becomes flaccid, then plasmolysed.
4. Water molecules move down a water potential gradient.

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33
Q

Explain the effects of osmosis when water moves OUT animal cells.

A

Description:
-Shrink, Crenate

Explanation:
1. Cell has a higher water potential than solution.

  1. Water moves OUT of cell by osmosis.
  2. Cell shrinks and then crenates.
  3. Water molecules move down a water potential gradient.
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34
Q

Explain the effects of osmosis when water moves IN animal cell.

A

Description:
-Expand, burst (no cell wall)

Explanation:
1. The solution has a higher water potential than the cell.
2. Water moves into cell by osmosis.
3. Cell expands and bursts.
4. Water molecules move down a water potential gradient.

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35
Q

Where to find concentration of plant cell in graph?

A
  1. Zero change in mass/length
  2. Same water potential
  3. No net movement of water.
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36
Q

Explain how surface area to volume ratio affects THE RATE OF MOVEMENT OF SUBSTANCES

A

[One-cell organism]
-Has high surface area to volume ratio, Osmosis/ Diffusion very FAST.

[Multicellular Organism]
-Has small surface area to volume ratio, Osmosis/ diffusion very slow
Thus animals need transport system.

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37
Q

IODINE SOLUTION TEST

A

Nutrient: Starch

[Descriptions]
1. Place food samples on a white tile and drop a few drops of iodine solutions.

[Observations]
BROWN -> BLUE/BLACK.

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38
Q

BENEDICT’S SOLUTION

A

Nutrient: Reducing Sugar

[Descriptions]
1. Set up a boiling water bath.
2. Place 2cm3 of Benedict’s solution into an equal volume of food sample.
3. Place in boiling water bath for 3 to 5 mins.

[Observations]
BLUE -> GREEN -> YELLOW -> ORANGE -> BRICK-RED PRECIPITATE

+Non reducing sugar: Sucrose+

39
Q

BIURET SOLUTION

A

Nutrient: Protein

[Descriptions]
1. Add 2cm3 of food sample, then add Biuret solution, drop by drop, shaking after each drop.

[Observations]
BLUE -> VIOLET

40
Q

ETHANOL EMULSION

A

Nutrient: Fats

[Descriptions]
1. Add 2cm3 of water to 2cm3 of food sample.
2. Add 2cm3 of ethanol.
3. Shake thoroughly.

[Observations]
A cloudy white emulsion is formed.

41
Q

(3) What are the ROLES of water in living organisms

A
  1. RAW Material for photosynthesis
  2. Main component of blood to carry dissolved nutrients to different parts of the body.
  3. Help to regulate temperature (prevents wilting)/ water loss through transpiration in a plant, pulls water into leaf cells for photosynthesis.
42
Q

What are enzymes?

A

Biological catalysts, made up of proteins, speed up metabolic reactions.
-Remain chemically unchanged at the end of a reaction.

43
Q

(2) Properties of enzymes

A

-Made up of proteins
-Are required in minute (small) amounts

44
Q

Explain enzyme action in terms of lock and key hypothesis.

A
  1. Key, substrate, must have a complementary shape to the lock, the enzyme’s active site.
  2. This allows the substrate to FIT into the active site.
  3. Forming an enzyme-substrate complex.
  4. A chemical reaction will OCCUR.
  5. Substance broken down into products (name).
  6. Enzye remains CHEMICALLY UNCHANGED at the end of the reaction.
45
Q

SEQUENCE OF ENZYME ACTION in LOW TEMPERATURE (0-10deg).

A
  1. Enzymes are INACTIVE.
  2. Lesser Kinetic Energy, decreased chances of substrate and enzymes colliding is low.
  3. Low formation of Enzyme-Substrate Complex.
46
Q

SEQUENCE OF ENZYME ACTION in INCREASING TEMPERATURE (11-35 deg).

A
  1. Enzymes are more active.
  2. More Kinetic Energy, chances of substrate and enzymes colliding is increased.
  3. Higher formation of enzyme-substrate complex.
47
Q

SEQUENCE OF ENZYME ACTION in OPTIMUM TEMPERATURE (37 deg).

A
  1. Enzymes are most active
  2. Higher Kinetic energy, chances of substrate & enzymes colliding is increased.
  3. Highest/ most amount formation of enzyme-substrate complex.
48
Q

SEQUENCE OF ENZYME ACTION in BEYOND OPTIMUM TEMPERATURE (45-100 deg).

A
  1. Enzymes are denatured.
  2. Kinetic Energy is too high, such that the Active site of enzymes is lost.
  3. Gradually, there will lesser and no enzyme-substrate complex that can be formed.
49
Q

SEQUENCE OF ENZYME ACTION in Optimum pH.

A
  1. Enzymes are most active.
  2. High formation of enzyme-substrate complex.
50
Q

SEQUENCE OF ENZYME ACTION in Extreme changes in pH.

A
  1. Enzymes denatured
  2. No enzyme-substrate complex formation as the enzyme’s active site is lost.
51
Q

A petri dish was filled with agar jelly containing starch. Four holes were cut in the jelly. Each hole was filled with A: distilled water B: amylase and acid C: amylase solution D: boiled amylase. After 30 minutes, the iodine solution was poured over the jelly.
Which hole has the largest yellow-brown region
surrounding it? Explain why.

A

A: No enzymes, cannot digest. Starch present, iodine solution turn from brown to blue-black.

B: Enzymes is denatured (amylase-mouth (7), small intestine(9), lose active site, unable to form enzyme-substrate complex. Starch present, iodine solution turn from brown to blue-
black.

C: Enzymes is active, substrate fits enzyme’s active site, form enzyme-substrate complex to
break down starch. STARCH IS ABSENT. It will have the largest yellow-brown region.

D: Enzymes is denatured, lose active site, unable to form enzyme-substrate complex. Starch
present, iodine solution turn from brown to blue-black.

52
Q

Explain enzyme action in biological washing powder (37 degree)

A

There are enzymes in washing powder. They contain carbohydrase, protease and lipase.

-Protease to break down blood, eggs, gravy stains
-Lipase breaks down fats and grease
-Carbohydrase breaks down starches.

After breaking down, they become soluble and thus dissolve in water and is washed away.

53
Q

Explain enzyme action in meat tenderisers

(E.g):
The unripe fruit of the papaya tree contains a particular type of digestive enzyme that is often
used to soften meat. Infer the kind of organic molecule that this enzyme acts on.
Suggest how this enzyme may cause the effect of softening meat.

A

Protease. Breaks down protein to polypeptide.

54
Q

Sequence of nutrition processes

A

ingestion -> digestion -> absorption -> assimilation
(ingestion -> egestion)

55
Q

Compare and contrast between physical and chemical digestion

A

[Physical digestion]
-No enzymes
-Mechanical breakdown of food into
smaller particles (still complex and insoluble)

[Chemical digestion]
-Uses enzymes
-Chemical breakdown of food into smaller, simpler & soluble molecules for absorption.

56
Q

State the physical and chemical digestion process in MOUTH (pH7).

A

Physical digestion:
Chewing
-increases surface area to volume ratio of food for more effective enzymes action

Chemical digestion:
(salivary amylase)
starch -> maltose

57
Q

State the physical and chemical digestion process in STOMACH (pH2)

A

Physical digestion:
Peristalsis helps to mix food with gastric juice. Increase collision of
enzymes with substrates

Chemical digestion:
(pepsin (protease))
protein -> polypeptides

58
Q

State the physical and chemical digestion process in SMALL INTESTINE (pH9)

A

Physical digestion:
-Peristalsis helps to mix food with gastric juice.
-Increase collision of
enzymes with substrates
-Emulsification of fats (large fat droplets become tiny fat droplets),
increases surface area to volume ratio of food for more effective
enzymes action

Chemical digestion:
(pancreatic amylase) (intestinal maltase)
starch -> maltose -> glucose

(pancreatic trypsin) (intestinal peptidase/erepsin)
protein -> polypeptides -> amino acids

(lipase (both pancreatic and intestinal))
fats -> fatty acids + glycerol

59
Q

Adaptation of the MOUTH and what happens when it is removed/ disease/ disorder (the teeth)

A

[Adaptations]
-Teeth for chewing
-Salivary glands secreting amylase at pH7

[Removed]
(people who lose their
teeth)
-Physical digestion through
chewing will be reduced.
-Eat soft or liquid foods.

60
Q

Adaptation of the OESOPHAGUS and what happens when it is removed/ disease/ disorder

A

[Adaptations]
-Muscles to contract & relax to push forward

[Removed]
(astronauts, need a
functioning oesophagus)
-Need to push food into
the stomach for digestion

61
Q

Adaptation of the STOMACH and what happens when it is removed/ disease/ disorder

A

[Adaptations]
-Muscular bag, how much it is able to extend
-determine the amount that you can eat

[Removed]
{e.g. gastric bypass, balloon
stomach, ulcers}
-Frequent Smaller meal
-Weight loss

62
Q

(6) Adaptation of the SMALL INTESTINE and what happens when it is removed/ disease/ disorder

A

[Adaptations]
1. 6m long
-Long enough to Complete digestion & absorption

  1. Intestinal juice, alkaline (pH 9)
    -Provide enzymes to work at optimum conditions
  2. Highly coiled, villi, microvilli
    -Increase surface area to volume ratio for faster absorption
  3. Intestinal cells have a lot of
    MITOCHONDRIA to release energy required,
    -to continually absorb all digested food substances (against their concentration gradient)
  4. Intestinal epithelium layer- 1 cell thick
    -Short diffusion distance
  5. Richly supplied with blood capillaries
    -Maintain concentration gradient for
    continual absorption

[Removed]
-Incomplete digestion and
absorption {e.g. celiac
disease}
-Small frequent meals

63
Q

Adaptation of the PANCREAS and what happens when it is removed/ disease/ disorder

A

[Adaptations]
-Provides enzymes with alkaline medium (pH9) (lipase, amylase, trypsin)
-Produces and secretes hormones that regulate blood glucose level

[Removed]
{e.g. pancreatitis}
-Reduced chemical digestion -> incomplete digestion
-Unable to control blood sugar level
-Small frequent meals

64
Q

Adaptation of the GALL BLADDER and what happens when it is removed/ disease/ disorder

A

[Adaptations]
-Store bile (produced by liver)

[Removed]
-Bile duct is blocked by gall stones, bile is not able to go into the small intestine.
-Cannot emulsify fats, lowers rate of lipase digestion
-Oily faeces -> float on the
surface
-Avoid food with fats

65
Q

Describe and Explain how digestion occurs in the digestive
system given A HAMBURGER.

A

[MOUTH (only
carbohydrates)]

Physical digestion:
Chewing breaks down hamburgers into smaller pieces to increase surface area to volume ratio for faster enzyme action.
Chemical digestion:
(salivary amylase)
starch in bread -> maltose

[STOMACH (only proteins)]

Physical digestion:
Peristalsis helps to mix food with gastric juice. Increase collision of
enzymes with substrates
Chemical digestion:
(pepsin (protease))
protein in meat -> polypeptides

[SMALL INTESTINE
(carbohydrates,
proteins and fats)]

Physical digestion:
Peristalsis helps to mix food with gastric juice. Increase collision of
enzymes with substrates
Emulsification of fats (large fat droplets become tiny fat droplets),
increases surface area to volume ratio of food for more effective
enzymes action

Chemical digestion:
(pancreatic amylase, intestinal maltase)
starch in bread -> maltose -> glucose

(pancreatic trypsin, intestinal peptidase/erepsin)
protein in meat -> polypeptides -> amino acids

(lipase (both pancreatic and intestinal))
fats in meat -> fatty acids + glycerol

66
Q

Describe at least 3 ways how Carbohydrates, Proteins, and Fats are assimilated.

A

[Carbohydrate]
-Release energy for cell activities (1st source of energy)
-Excess, storage- glycogen
-Can be converted to other nutrients if the body requires

[Protein]
-Growth and repair
-Synthesis of enzymes and hormones
-Last source of energy (survival)

[Fats]
-Provides insulation, prevents heat loss
-Prevent water loss
-2nd source of energy

67
Q

(6) Describe the processes in the liver and explain how it is
important.

A

[Regulate blood
glucose concentration]
(Insulin)
-Excess glucose -> Glycogen (storage)
(Glucagon)
-Ensure sufficient glucose for respiration, and if in excess, store
glucose as glycogen.

[Deamination]
-Breakdown excess amino acids
-Amino group converted to urea, excreted out of body in
mainly in urine, a bit via sweat.
-Acidic group converted back to glucose.

[Protein Synthesis]
-To synthesize proteins needed for blood clotting (platelets).

[Production of bile]
-Bile emulsify fats, increase surface area to volume ratio of fat droplets, FASTER lipase action
Neutralise stomach acids

[Storage of iron]
-Forms haemoglobin

[Detoxification]
Alcohol (toxic form)-> acetaldehyde/-alcohol dehydrogenase (non-toxic)

68
Q

(3) What is the function of WHITE BLOOD CELLs? (Phagocytes & lymphocytes)

A

White blood cell - large and odd-shaped nucleus

  1. Destroy bacteria & foreign substance
  2. Engulf and digest bacteria & foreign substances.
  3. Produce antibodies to neutralize toxins. (Lymphocyte)
69
Q

Describe the effects of alcohol

A
  1. Causes liver cirrhosis (liver cells unable to function, “hardens” liver, accumulated damage over time as liver cell are overworked)
  2. Slows down brain function – decrease in awareness
  3. Reduces self-control
  4. Increased risks of gastric ulcers
  5. High blood pressure
70
Q

What is the function of PLATELETS?
Describe how BLOOD CLOT works.

A

-Help to clot blood

How blood clot forms:
1. Damaged tissues release thrombokinase

  1. Thrombokinase converts PROTHROMBINE -> THROMBIN.
  2. To activate Thrombin which allows Fibrin Threads to form to entangle blood cells form fibrinogen to form a blood clot.
71
Q

(2) Explain the PROTECTIVE FUNCTION of blood.

A

[White blood cells]
-Destroy bacteria & foreign substances when a person is sick/ has a cut/ injury.
-Engulfing & digesting them.
-Neutralise toxins.

[Platelets]
-Clot blood when there is a cut/ injury.
-preventing excessive blood lost.

72
Q

(2) Application of Protective Function of Blood in ORGAN TRANSPLANT and TISSUE REJECTION.

A

[Organ Transplant]
Patients must take immunosuppresants (eat for life to prevent white blood cells from engulfing and digesting away the new organ.)

[Tissue Rejection]
Phagocyte (WBC) will engulf & digest as it is considered to be foreign.

73
Q

Is BLOOD a TISSUE? Explain why.

A

Blood is a tissue because…
it is made up of different types of cells for a common function (Transport medium);
connects the body systems together bringing the needed oxygen, nutrients, hormones & other signaling molecules, & removing the waste.

74
Q

(3) Compare and Contrast between the
different blood vessels.

A

[Artery]
- Carries blood away from
the heart
- Thick muscular and
elastic walls
- Fast blood flow, spurts
- High blood pressure
- No valves

[Capillary]
- Carries blood to body
cells for exchange of
materials
- One-cell thick layer (short
diffusion distance)
- Slow blood flow
- Low blood pressure
- No valves

[Vein]
- Carries blood back to the
heart
- Thin muscular and elastic
wall
- Slow blood flow
- Low blood pressure
- Has VALVES to prevent
backflow of blood (blood
move to heart)

75
Q

Blood pressure graph in Artery.

A

-Arteries receive the HIGHEST pressure of blood flow and are THICKER and more ELASTIC to accommodate the high pressures.

-Smaller arteries, such as arterioles, have more SMOOTH MUSCLE, which contracts or relaxes to regulate blood flow to specific portions of the body.

-High branching of arteries to capillaries, lowers the blood pressure. Enough pressure is needed to ensure blood ad oxygen is sent to the organs to deliver what is needed for
cell activities.

-Blood pressure decreases from arteries to veins, and this is because of the pressure overcoming the resistance of the vessels.

76
Q

Blood velocity graph in Veins.

A

-The blood velocity is higher in large veins than in the capillaries.

-The cross-sectional area of capillaries is the largest, the LARGER this area is, the SLOWER the velocity of blood is.

-And so blood in large veins travels faster
than in capillaries.

77
Q

Explain the advantages of
double circulation.

A

-Fully oxygenate the blood (to the lungs).

-Oxygenated blood quickly distributed to all organs (to body) for aerobic respiration to release energy for cell activities.

78
Q

Describe blood flow in the heart.

A

Vena Cava -> Right atrium -> Right Ventricle -> Pulmonary artery -> lungs -> pulmonary vein ->
left atrium -> left ventricle -> Aorta -> Body -> vena cava

79
Q

(4) Describe and Explain the processes in the CARDIAC CYCLE.

A

[Slight pressure rise in atria]
-Both atria filled with blood from vein.
-Atria contracts, force blood into ventricles.
-Tricuspid & bicuspid valve opens.

[Pressure in ventricles rise] -Ventricles contract.
-Tricuspid & bicuspid valve close to prevent backflow to atria.

[Pressure in ventricles higher than aorta]
-Semi-lunar valves open.
-Blood leaves the heart.
-As ventricles contracts, atria contract and
gets filled with blood again.

[Fall in pressure in ventricles]
-Ventricles relax.
-Semi-lunar valves close to prevent backflow of blood to heart.

80
Q

Describe coronary heart disease.
Differentiate it from
cardiac arrest/ heart attack.

A

[Coronary Heart Disease]
- Plaque/hardened fatty deposits buildup in coronary artery, narrows
the lumen.
- Reduced blood flow to heart.
-Lower supply of oxygenated blood to
heart muscles (chest pain).

[Heart Attack]
-Blood clot causes complete blockage in narrowed coronary artery with high buildup of fatty deposits.
-No blood supply to heart.
-Heart muscles unable to contract as no energy.

81
Q

Identify the RISK FACTORS and PREVENTIVE MEASURES for coronary
heart disease.

A

[Risks]
-High saturated fat & cholesterol diet
-Smoking (increases fatty deposits)
-Sedentary lifestyle (increases fatty deposits)
-Stress (Narrows lumen)

[Prevention]
-Eat less saturated fats & cholesterol
-No smoking
-Exercise REGULARLY
-Get a hobby

82
Q

Word equation for aerobic & anaerobic respiration

A

[Aerobic]
glucose + oxygen -> carbon + water + energy
dioxide

[Anaerobic]
(in muscles)
glucose -> lactic acid + energy

(with yeast in baking, making alcohol)
glucose -> ethanol + carbon + energy
dioxide

83
Q

Compare & Contrast between Aerobic and Anaerobic Respiration.

A

[Aerobic]
-Uses oxygen
-Releases large amount of energy
-In mitochondria
-Carbon dioxide and water is produced
-Complete breakdown of glucose

[Anearobic]
-Does not use oxygen
-Release small energy
-In cytoplasm
-Lactic Acid is produced
-Incomplete breakdown of glucose

84
Q

How can you identify from HYDROGEN CARBON INDICATOR that aerobic respiration has occurred?

A

[Yellow/ Acidic]
-Respiration ONLY.
-Large amount of carbon dioxide.

[Yellow/ Acidic - Red/ Neutral)
-Respiration & Photosynthesis rate almost the same.
-Carbon dioxide produced and removed almost at similar rate.

[Red/Neutral - Purple/ Alkaline]
-Respiration & Photosynthesis rate almost the same.
-Carbon dioxide produced and removed almost at similar rate.

[Purple/ Alkaline]
-High rates of photosynthesis as compared to respiration/removal
of carbon dioxide in tube.

85
Q

(4) How can you identify from LIMEWATER/ SODALIME that aerobic respiration has occurred?

A

-White PPT
-Presence of carbon dioxide, respiration/exhalation has occurred
-Remains clear
-No carbon dioxide released, no respiration/exhalation.

86
Q

(6) Explain how anaerobic respiration has occurred during strenuous exercise and its after-effects.

A

-Maximum aerobic respiration cannot release energy fast enough to meet the body’s demands breathing & heart rate has increased to allow more oxygen to reach the muscles.

-Muscle cells undergo anaerobic respiration to release extra energy and lactic acid is formed in the process

-Insufficient oxygen to meet the demands of the muscular contractions, the muscles incur an oxygen debt (oxygen supply is lower than oxygen demand).

-Body experiences fatigue and muscular pains.

-During rest, breathing rate continues to be fast for some time (oxygen intake
remains high for some time to repay oxygen debt).

-All the lactic acid has been converted, the oxygen debt is repaid.

87
Q

State the pathway that air enters the body.

A

Nostrils -> nasal passage
-> trachea -> bronchus -> bronchioles -> alveoli

-Oxygen then dissolves in thin film of moisture & diffuse into blood capillaries.

88
Q

Compare and Contrast between cilia in the trachea and bronchi
and the microvilli in the small intestine.

A

[Microvilli] Cilia
-High surface area to volume ratio to increase
absorption of digested food substances.

-Does not provide any force to move substances.

[Cilia]
-Does not provide high surface area to volume
ratio for absorption.

-Provides the propelling force for the transport
of mucus along the airways.

89
Q

Distinguish between chronic bronchitis and emphysema

A

[Chronic Bronchitis]
(persistent coughing to clear air passage)
-Lining of air passages becomes inflamed excessive mucus secreted.

-cilia paralysed -> mucus cannot be removed

-air passage blocked -> difficulty breathing

[Emphysema]
(Alveoli break, overall surface area to volume
ratio shrink)

-Fewer alveoli,
Lesser oxygen

90
Q

(3) Identify measures to deal with infectious diseases.

A

[Through droplets in the air]
(e.g., coughs/sneezing within close range)

How to deal with it:
-Wear mask when sick
-Wash hands with soap regularly
Stay home when sick

[By direct contact]
a. Exchange of body fluids e.g. blood,
vaginal fluids, semen
[Skin/mucous membrane]

How to deal with it:
-Wear gloves
-Go to licensed shops for piercing, disposable
needles (doctor)
-Avoid touching your eyes, nose and mouth

[By contaminated food and water]
(chloera)
Housefly / objects & surfaces
(pneumococcal disease)

How to deal with it:
-Cover food
-Practice hygienic food preparation and storage
-Having good personal hygiene
(e.g. Sanitise surfaces & objects regularly)
-Maintain a clean water supply
-Ensure proper sewage treatment

91
Q

Explain antibiotic resistance.

A

When course of antibiotics not completed:
-Not all bacteria killed
-Surviving bacteria continue to multiply and grow stronger
-Develop resistance

92
Q

How does the body react to vaccines?

A
  1. WBC BINDS TO Agent that resembles a pathogen.
  2. WBC is stimulated to divide.
  3. WBC produce antibodies.
  4. Antibodies destroy the agent in the vaccine,
  5. Some of these WBC remain in the bloodstream. In the future, if the live pathogens enter the bloodstream, the WBC will recognize them and quickly produce antibodies to destroy the pathogens before they infect our cells.
93
Q

(3) Explain how the presence of gall stones will affect digestion in the small intestine.

A
  1. Lesser bile released
  2. Lesser emulsification/slow fat digestion
  3. Reduced overall digestion as pH may not be optimum
94
Q

(2) Suggest changes in the diet for patients with gall stones.

A
  1. Decrease fat intake
  2. Eat smaller portions of food

O Levels (4 decks)

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