L13- Bone, Marrow Vessels And Blood Flashcards
What are the types of bones?
- Long
- Short
- Flat
- Irregular
- Sesamoid
Outline the a) location b) structure and c) function of each bone type
- Long
A) Appendicular skeleton- femur
B) longer than wider
C) to support the weight of the body and facilitate movement - Short
A) wrist (carpals) and ankle (tarsals) joints
B) same length and width
C) provide stability and movement - Flat
A) skull, thoracic cage and pelvis
B) flattened with roughly parallel opposite edges
C) protects internal organs and provides large areas of attachment for muscles - Irregular
A) vertebrae and pelvis
B) vary in shape and structure
C) protects internal organs, important anchor points muscle groups - Sesamoid
A) embedded in tendons of hands, knees and feet
B) Small round bones
C) protects tendons from stress and damage and repeated wear and tear
What are the two types of bone tissue?
- Cancellous/spongy bone (inner layer of all bones)
2. Compact bone/cortical bone (outer layer of all bones)
Compare the two types of bone marrow
Red marrow:
- full of developing blood cells
- rich blood supply
- found in spongy bone only
- function: replenish cells in the blood (haemopoiesis)
Yellow marrow:
- full of adipocytes
- poor blood supply
- function: shock absorber and energy source
- can convert to red marrow
How does bone marrow cells differ from cells in blood?
- Bone marrow is where stem cells are made
- stem cells are blood cells at the earliest stages of development (not specialised)
- all our blood cells develop from stem cells in the bone marrow
Where do you find bone marrow in your body?
Ribs, vertebrae, sternum and bones of pelvis
What are the types of blood vessels in your body?
- Arteries (and arterioles)
- Capillaries
- Veins and venules
a) Function of arteries
b) Structure of arteries
a) Elastic blood vessels that carry blood AWAY from the heart
- high blood pressure: small lumen diameter and the elastin allows it to stretch but prevents over expansion
b) 3 layers: (inside to out)
1. Tunica intima: elastic membrane lining and smooth endothelium (non-fenestrated)
2. Tunica media: composed of smooth muscles and elastic fibres. this layer is thicker in arteries than in veins and has two distinct elastic layers
3. Tunica externa: strong outer covering composed of collagen and elastin
a) Function of capillaries
b) Types of capillaries
c) Structure of capillaries
a) The capillaries are responsible for facilitating the transport and exchange of gasses, fluids, and nutrients in the body.
b) Continuous, fenestrated and sinusoid
c) Smallest blood vessels. Two layers: endothelial layer surrounded by a basement membrane
A) What is flow through capillaries known as?
B) How is capillary flow controlled?
a) Microcirculation
b) By Precapillary sphincters located between arterioles and capillaries
- contain smooth muscle for contraction
- when they are open, blood flows freely to capillary beds
- when they are closed blood cannot flow to beds
a) Function of veins
b) Structure of veins
a) Elastic blood vessel that transports blood to the heart
- Low pressure system
- fibroelastic cartilaginous valves to prevent backflow
b) 3 layers: (inner to out)
1. Tunica intima; endothelial cells
2. Tunica media; elastic fibres and smooth muscles
3. Tunica externa: elastic fibrous capsule
What are the types of veins?
- Pulmonary veins: carry oxygenated blood from lungs to the left atrium of the heart
- Systemic veins: return oxygen-depleted blood from rest of the body to the right atrium of the heart
- Superficial veins: located close to the surface of the skin not near an artery
- Deep veins: located deep between tissues and are located near a corresponding artery
a) How do veins range in size?
b) What are the smallest veins in the body?
c) what are the largest veins in the body?
a) 1mm to 1-1.5cm in diameter
b) Venules
c) Superior and inferior vena cavae
What is the order of blood flow
Superior and inferior vena cava –> RA –> artery –> arterioles –> capillaries –> venules –> veins–> vena cava
Compare the structure and function between veins and arteries and capillaries
- Arteries have much thicker walls (strength and elasticity) to deal with the higher blood pressure, prevent bursting and maintain pressure wave
- Capillaries: Thin walls and narrow lumen to bring blood into close contact with tissues to allow diffusion of materials between capillary and tissues
- Veins have wider lumens; to offer less resistance to blood flow
