B3.2 Transport Vocab

Endothelium cells

Single layer of cells that are coated with the basement membrane.

Basement membrane

Extracellular fibrous, cross-linked proteins that act as a filter to allow some small and medium molecules to leak out of capillaries.

Pores

Found between the endothelium cells, make capillary highly permeable.

Tissue fluid contents

Similar to blood plasma. Contains oxygen, glucose and all other substances in blood plasma EXCEPT large protein molecules.

Fenestrated capillaries

Contain a large number of pores in the walls for areas that require larges volumes of tissue fluid and faster transport. Ex. Glomerulus in the kidney.

Structure of veins (5 components)

1. Thin walls

2. No visible wall fibers

3. Flattened

4. No inner surface corrugation

5. Wide lumen

Structure of arteries (5 components)

1. Thick walls

2. Circular

3. Visible wall fibers

4. Inner surface corrugation

5. Narrow lumen

How does the narrow lumen of arteries help them to perform their function of transporting blood away from the heart?

Maintains high blood pressures and high velocities of blood flow.

How do the thick fibrous walls with collagen of arteries help them to perform their function of transporting blood away from the heart?

Can expand, contract, and withstand high pressure without bursting without bulging (aneurysm) or bursting.

How do the elastic fibers of arteries help them to perform their function of transporting blood away from the heart?

Stretch at peak pressure and provide recoil to push blood through and requires less energy than a full contraction.

How do the muscular walls of arteries help them to perform their function of transporting blood away from the heart?

Contract to push blood through.

Systolic pressure

Peak pressure in an artery.

Diastolic pressure

Minimum pressure inside of an artery.

Vasoconstriction

Smooth muscle contracts and lumen narrows reducing flow of blood along an artery or arteriole.

Vasodilation

Smooth muscles relaxes and lumen widens to increase blood flow along an artery or arteriole.

How does the wide lumen of veins help them to perform their function of transporting blood back to the heart?

Low pressure, easier for muscles to squeeze.

How does the thin muscle wall of veins help them to perform their function of transporting blood back to the heart?

Easier for muscles to squeeze.

How do the pocket valves of veins help them to perform their function of transporting blood back to the heart?

Prevent back flow of blood due to low pressure in veins.

Atheroma

Also known as plaque. Made up of a variety of lipids, including cholesterol.

Angina

Chest pain due to restriction of blood flow to the heart.

Thrombosis

The formation of a blood clot due to fatty deposits becoming saturated with calcium salts and hardening.

Heart attack

When a blood clot blocks the flow of blood to part of the heart, depriving it of oxygen and preventing normal contractions.

Myocardial infarction

Tissue death in heart muscle due to inadequate blood supply.

Coronary Heart Disease (CHD)

Conditions associated with narrowed or blocked coronary arteries.

How do the dead and hollow cells of xylem vessels allow for transport of water?

Maintenance of a continuous water column.

How does the lignin (polysaccharide) of xylem vessels allow for transport of water?

Prevents collapse.

How do the pits of xylem vessels allow for transport of water?

Water can pass through.

Function of xylem

Water transport

Function of phloem

Sugar transport

Function of epidermis

Protection/water proofing

Function of cortex

Supports vascular bundles/where photosynthesis is happening

Function of pith

Provides bulk to stem