Body and its internal environment

Question 1

Nucleus

Answer 1

Contains DNA (deoxyribonucleic acid) on chromosomes

Question 2

Endoplasmic Reticulum

Answer 2

‘Rough’ ER synthesises proteins, ‘smooth’ ER synthesises lipids

Question 3

Golgi body

Answer 3

Protein modification and packaging into vesicles for secretion

Question 4

Mitochondria

Answer 4

ATP production/synthesis (so liver and muscles have more) contains DNA

Question 5

Lysosome

Answer 5

Contains enzymes, breakdown/recycle unwanted chemicals and proteins/food

Question 6

Secretory granules (vesicles)

Answer 6

Contains a product to be released into circulation eg. Insulin into the blood, granules bind to the plasma membrane and contents released by exocytosis

Question 7

Simple squamous:

Answer 7

Flat, 1 layer thick
Important for exchange or gases/nutrients
Eg. Alveoli in the lungs

Question 8

Stratified squamous:

Answer 8

Flat, many layers
Protection and barrier (communication)
Eg. Oral cavity

Question 9

Keratinised stratified squamous:

Answer 9

Flat, many layers (Keratin)
Protection and barrier (waterproofing)
Eg. Skin, hair

Question 10

Simple Cuboidal:

Answer 10

Cuboidal shape, 1 layer
Secretion and absorption
Eg. Salivary glands, pancreas

Question 11

Simple Columnar:

Answer 11

Tall cells, with basely located nuclei, 1 layer
Absorption and secretion
Eg. GI tract (gall bladder)

Question 12

Modified Simple Columnar:

Answer 12

Tall cells, basely located nuclei, 1 layer
Modifications eg. Microvilli
Absorption and secretion
Eg. Enterocytes in GI tract

Question 13

Complex Columnar:

Answer 13

Appear stratified
Modifications eg. Cilia, goblet cells
Mucociliary escalator
Eg. Trachea, large respiratory airways

Question 14

How does the body maintain fluid balance?

Answer 14

ADH
Not enough water:
- A message is sent to the anterior pituitary gland causing it to release ADH
- travels into bloodstream to the kidneys affecting the tubules, causing more water to be reabsorbed into the blood
- Produces a smaller volume of more concentrated urine = level of water in the blood increases back to normal
Too much water:
- The release of ADH from the anterior pituitary gland is slowed down/stopped
- Kidneys therefore will not save as much water
- A large volume of dilute urine is produced = level of water in the blood falls back to normal

Question 15

Define the term electrolytes

Answer 15

Ions that can conduct electricity, and can move across the cell membrane by osmosis if water follows

Question 16

Hypokalaemia effects

Answer 16

Abnormal ECG, bradycardia, muscle cramps, decreased tone in muscles

Question 17

Hyperkalaemia effects

Answer 17

Irritability, muscle weakness, extreme cardiac arrest

Question 18

Hypercalcaemia effects

Answer 18

Fatigue, weakness

Question 19

Hypocalcaemia effects

Answer 19

Muscle cramps, neuromuscular excitability

Question 20

Active transport

Answer 20

Against concentration, requires ATP

Question 21

Facilitated diffusion

Answer 21

Down concentration gradient, with carrier, does not require energy

Question 22

Role of Sodium?

Answer 22

Osmotic balance
Body fluid volume
Nerve conduction
Acid-base balance

Question 23

Role of Calcium?

Answer 23

Bone formation
Muscle contraction
Blood clotting
Nerve impulses

Question 24

Role of Chloride?

Answer 24

Essential for gastric acid production

Balancing ion

Question 25

Role of Phosphate?

Answer 25

Acid-base balance
Bone formation
Metabolism of carbs
Found in DNA

Question 26

Role of Potassium?

Answer 26

Nerve conduction - higher concentration inside the cell

Carbohydrat