Systems Flashcards
What is physiology?
Mechanisms of living things - cell function at ionic & molecular level to integrated behaviour of the whole body
What is pathophysiology?
The study of when function goes wrong in disease
Explain the scientfic method
1)Idea/thought 2)Hypothesis(testable) 3) Theory - reproducible experimental data 4) Facts (very few in science)
How many body systems are there?
11
Name the body systems?
Skeletal, muscular, nervous, digestive, urinary, respiratory, circulatory, endocrine, immune, integumentary, reproductive
What is a system?
Group of organs that perform a specific function
What is integration?
An overlap between systems
How many bones in the human body?
206 bones
How many ribs are there?
24 - 12 pairs
What is the function of the ribs?
Support weight & withstand force of contracting muscles
Explain osteoblasts?
Make bone via deposition
Explain osteocytes?
Terminally differentiated osteoblasts trapped in a matrix of hydroxyapatite (Ca2+ mineral) & osteoid (protein)
Explain osteoclasts?
Break down bone (resorption) - secrete acid to break down hydroxyapatite & enzymes to breakdown osteoid
What processes allow for bone repair?
Resorption & deposition
When and how do bones weaken?
> 30 years - resorption>deposition
What disease is caused by a lack of growth hormone?
Achondroplasia
Explain achondroplasia?
Lack of GH - dwarfism - children can receive GH treatment
When do long bones stop growing?
When the epiphyseal plate is calcified
Explain bone development
Long bones grow in childhood - chondrocytes divide & enlarge in response to growth hormone - trapped in calcification in bone - die & replaced by osteoblasts - process stops in adolescents when the epiphyseal plate is calcified
Name & give a function for the types of muscles
Skeletal - move skeleton except tongue, anal sphincter, & diaphragm
Cardiac - allows contractions of heart
Smooth - contraction & relaxation of vasculature & digestive system
How many nerve cells are in the brain?
10^11 nerve cells (0.1% cells) - 10^14 synapses
What do nerve cells do?
Connect body to brain - conduct electrical impulses - control muscle movement, hormone secretion & be blocked by neurotoxins
How long is the GI tract?
4.5m Tube from mouth to rectum
Explain some functions of the digestive system?
Water & food enter the body, nutrients absorbed, waste gas exit via lungs, waste water excreted via kidneys, unabsorbed materials exit in the form of faeces
Explain the function of the urinary system?
Water is absorbed in blood & kidney regulates total amount of water via secretion & reabsorption - excess lost via excretion
Explain the respiratory system’s function?
Diaphragm contracts & relaxes - moves lungs which drives gas exchange - ATP produced by most cells - O2 & glucose used, CO2 & Water released
How many times does our heart beat?
3,000,000,000
How much blood is pumped by the heart?
70ml/beat - 72 bpm
Explain some functions of the circulatory system?
Transport: O2 carried by erythrocytes, nutrients dissolved in blood, CO2 & waste excretion, hormones
Explain the flow of blood
Deoxygenated blood enters the right side of the heart, pumped to the lungs, re-enters the left side of the heart and pumped into systemic circuit
Explain the immune system?
Innate & adaptive immunity - inflammatory response
Explain the integumentary system?
Skin = largest organ - skin, gland, & their products (mucous, sweat), protects & informs of surroundings (temp/touch regulators), colour determined by level of melanin, sweat is part of the innate immune system (pH4 - prevent bacterial colonisation)
What is the main goal of the reproductive system?
Egg & sperm fuse to give rise to offspring
What size is a human cell?
17μm
Explain where genes are located and their functions in the cell?
Chromosomes in nucleus, 3x10^9 bp DNA encodes 30,000 genes - DNA transcribed into RNA - translated into protein - determine function of cell
What is rhodopsin?
348aa - sensitive to light - located in retina
What is CFTR?
1,480aa Cl- ion transporter in secretory cells
