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Flashcards in Topic 1 Deck (19):

Describe the structure of a water molecule hydrogen bonding

One oxygen atom
Two hydrogen atoms
The oxygen is slightly negative
Hydrogen is slightly positive
Bond forms between oxygen and hydrogen


List some features of an Artery

-Thick wall to cope with high blood pressure
-muscle can contract or relax to increase/decrease blood flow to an area
-elastic tissue allows the artery to stretch/recoil during systole/diastole
-smooth inner layer of endothelium maximising blood flow


Name some features of a vein

-A relatively thin wall as they don't have to cope with high blood pressure
-smooth endothelium
-valves to prevent back flow


List some features of Capillaries

-single cell thick to minimise the distance of diffusion, allows molecules to diffuse quickly in and out of blood
-lumen smaller than diameter of a red blood cell, means RBC have to squeeze through giving more time for diffusion


List the first 5 events leading to atherosclerosis

1.Damage to endothelium
2.causes inflammatory response
3.white blood cells go into artery wall
4.white blood cells accumulate cholesterol
5.this accumulation is called an atheroma


List the final 4 steps leading to atherosclerosis

6.calcium salts and fibrous tissue build up forming a plaque- this is atherosclerosis

7. Atherosclerosis narrows lumen artery wall and reduces elasticity

8.this results in a higher blood pressure needed to pump blood

9.the higher blood pressure means further damage to artery walls is likely- positive feedback


List the 5 steps of a blood clot

1. Platelets come into contact with muscle tissue or connective tissue
2. Platelets and damaged tissue release thromboplastin
3. Thromboplastin catalyses the conversion of prothrombin Ito thrombin
4. Thrombin catalyses the conversion of fibrinogen into fibrin
5.fibrin is insoluble in water and forms a mesh, trapping blood cells


List 3 uncontrollable factors that can lead to CVD

1.Age-getting older
2.Gender-benign male
3.Genetics-a family history of CVD


List 5 controllable factors that can lead to CVD

-excessive alcohol consumption
-lack of exercise
-high cholesterol levels in blood


Glycogen found in plants/animals?



Function of glycogen/amylose/amylopectin

Glucose/energy store


Glycogen/amylose/amylopectin made of which monomer



Dose glycogen have side branches?

Yes- lots


Is amylose/ amylopectin found in plants or animals?



Amylose have any branches?



Amylopectin have side branches?

Yes- a few


Name the two polysaccharides that make up starch

Amylose and amylopectin


List 4 reasons polysaccharides are good energy stores

1) they are compact so lots of glucose can be stored in a small volume.
2)coiled, makes them more compact
3)insoluble in water so dose not affect water movement in/out of cell
4)are branched so can release glucose quickly


Describe the basic structure of a triglyceride

1 glycerol
3 fatty acid tails