Cells 1,2,4 - cells, tissue, fluid Flashcards
what is interstitial fluid composed of
Na+ high (sodium ions)
Cl- high (chloride ions)
K+ low (potassium ions)
what is intracellular fluid composed of
Na+ low (pump) (sodium ions)
CI- low (chloride ions)
K+ high (pump) (potassium ions)
how many litres of body water is there
42L
body water is made of what
28 L of intracellular fluid and 14 L extracellular fluid
body water is made of what
28 L of intracellular fluid and 14 L extracellular fluid
extracellular fluid is made of what
3L of plasma and 11 of interstitial fluid
what is the boundary between intracellular and interstitial fluid
cell membrane - selectively permeable
what is the boundary between interstitial fluid and plasma
capillary wall - permeable to small molecules
what is tonicity
The ability of an extracellular solution to make water move into or out of a cell by osmosis
what happens to a cell in hypotonic solution
the surrounding solution has a lower solute concentration than the cell’s cytoplasm. This creates a higher water concentration outside the cell than inside
cell gains water - swells
what happens to a cell in hypertonic solution
the surrounding solution has a higher solute concentration than the cytoplasm of the cell.
cell loses water - shrinks
what are systemic capillaries
allow for exchange of materials between blood and body tissues - water, nutrients, gases
Why does fluid leave the capillaries
Starling’s law of capillary
what is the net outward pressure in Starling’s law of capillary
12mmHg
what is the net inward pressure in Starling’s law of capillary
8mmHg
what is an example of a normal body input
Ingestion = fluid (1.25 L) and food (1 L)
Metabolism (350ml)
what is an example of an abnormal body input
Injection/infusion
Excessive drinking - polydipsia
what is an example of an abnormal body output
Gut (vomiting, diarrhoea)
Urine ( diabetes insipidus)
Breathing/skin (burns)
Sweating
haemorrhage
where does the 3 litres per day not reabsorbed in capillaries/venules go
Enters lymph vessels
Pumped to lymph nodes
Re-enters circulation near right atrium.
Name three cations found in the body fluids and state whether their concentration is higher inside or outside of the cell.
Sodium (Na⁺) – Higher concentration outside the cell (extracellular fluid).
Potassium (K⁺) – Higher concentration inside the cell (intracellular fluid).
Calcium (Ca²⁺) – Higher concentration outside the cell (extracellular fluid).
Name three anions found in the body fluids and state whether their concentration is higher inside or outside of the cell.
Chloride (Cl⁻) – Higher outside the cell (extracellular fluid).
Bicarbonate (HCO₃⁻) – Higher outside the cell (extracellular fluid).
Phosphate (HPO₄²⁻ / H₂PO₄⁻) – Higher inside the cell (intracellular fluid).
Name 5 transport methods by which molecules can cross the cell membrane.
simple diffusion
facilitated diffusion
active transport
Endocytosis & Exocytosis
osmosis
List 5 variables in the internal environment of the body that must be homeostatically maintained.
Body Temperature – around 37°C (98.6°F) for optimal enzyme function and metabolic processes.
Blood pH – 7.35–7.45 fot proper cellular function and enzyme activity.
Blood Glucose Levels – 70-110 mg/dL to provide energy for cells
Oxygen and Carbon Dioxide Levels – Oxygen is necessary for cellular respiration, while carbon dioxide must be removed to prevent acid-base imbalance.
Blood Pressure – 120/80 mmHg in adults) to ensure adequate blood flow and oxygen delivery to tissues.
List the 4 main tissue types and give an example of each.
Epithelial Tissue – Skin epidermis, lining of digestive tract
Connective Tissue – Bone tissue, blood
Muscle Tissue –Skeletal, cardiac muscle
Nervous Tissue – Brain and spinal cord tissue
what are the two types of epithelial tissue
- Lining e.g. ‘tubes’, ducts,
airways - Glandular e.g. thyroid,
pancreas etc.
what is an exocrine gland
Retains connection with surface epithelium via a duct.
what is an example of an exocrine gland
Salivary Gland
Secretion: Saliva (contains enzymes like amylase)
Site of Action: Mouth
Transport Method: Saliva is secreted through ducts directly into the mouth.
what is an endocrine gland
Loses connection to surface. Secretes into the blood.
what is an example of an endocrine gland
Pancreas
Secretion: Insulin
Site of Action: Liver, muscles, and other body cells
Transport Method: Insulin is released into the bloodstream and carried to target cells.
what is the Red blood cell concentration in men
e 5.4 x 10^6/microlitre (4.5-6.5)
what is the red blood cell concentration in women
4.8 x 10^6/microlitre (3.9-5.6)
what are the components for neative feedback
- Controlled variable
- Sensor
- Integrator
- Effector
- Compensatory response.
what is negative feedback
Acts to counteract the change in the controlled variable
what is an example of negative feedback
- Controlled variable — body temperature
- Sensor — nerve cells
- Integrator — temperature control centre
- Effectors — skeletal muscle (etc)
- Compensatory mechanism — heat production
what is positive feedback
reinforces the change in the controlled variable
what is an example of positive feedback
Contraction of the uterus at birth
Oxytocin —> contraction of uterine
smooth muscle —> moves baby
lower —> pressure on cervix —>
oxytocin release
what is Pathophysiology
a state in which normal function at any
organizational level is disrupted to the
extent that normal regulatory and
compensatory mechanisms cannot
maintain homeostasis.
name five subcellular organelles
nucleus
mitochondria
endoplasmic reticulum
golgi apparatus
ribosome
what is the function of a nucleus
Stores genetic material (DNA) and controls cell activities.
what is the function of the mitochondria
Produces energy (ATP) through cellular respiration.
what is the function of the endoplasmic reticulum
rough ER - protein synthesis
smooth ER - detox liver and calcium store
what is the function of golgi apparatus
Processes and packages molecules
into vesicles for transport.
what is the function of a ribosome
It assembles amino acids into proteins based on the instructions encoded in messenger RNA (mRNA).
what is an example of a normal body output
Gut (Faeces 100 ml)
Urine *(1.5 litres)
Breathing/Skin (900 ml)
Sweating (100 ml)
