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4.Analyse the results by comparing the total score with the following descriptors:

30 marks- you take very good care of your heart. Well done!

25 marks- you take good care of your heart. Keep it up!

20 marks- you take reasonably good care of your heart but need to work

on a few aspects where you scored 0.

15 marks- you need to take better care of your heart.

0-10 marks- you do not look after your heart at all. It’s time to make a

change to a healthier lifestyle.

Assessment Rubric

  • Results
0- not done1- poorly presented. 2- average presentation of results, but missing some detail.3- average presentation of results, including all salient featuresand information.4- good presentation of results, but missing some detail.5- good presentation of results, including all salient features and information.
5

Rich media:

Khan Academy

http :// www . khanacademy . org / video / circulatory - system - and - the - heart ? playlist = Biology

Cardiac Magnetic Resonance imaging of Beating heart: Large magnets are used to create images of the heart inside the body, without the need for surgery.

http://upload.wikimedia.org/wikipedia/commons/7/73/Four_chamber_cardiovascular_m agnetic_resonance_imaging.gif

View from the top

http://commons.wikimedia.org/wiki/File:Beating_Heart_axial.gif

View from the side

http://commons.wikimedia.org/wiki/File:Cardiac_mri_ani_sagittal_bionerd.gif

Blood vessels

Structure and functioning of arteries, veins, capillaries and valves

Arteries

  • Arteries carry blood from away from the heart. The pressure created by the pumping heart forces blood down the arteries.
  • Arteries have three layers.
  1. Outside layer – connective tissue
  2. Middle layer – smooth muscle, allows contraction of the arteries to regulate blood flow and pressure
  3. Inside layer – single layer of tightly connected simple squamous endothelial cells
  • The large arteries close to the heart branch into smaller arterioles (smaller arteries) and eventually branch into capillaries.

Capillaries

  • Capillaries are little more than a single layer or endothelial cells.
  • Capillaries form intricate networks throughout the tissues.
  • They allow water, nutrients and gasses to diffuse out of the blood and waste materials to diffuse into the blood.
  • This exchange occurs between the blood and the interstitial fluid.
  • The interstitial fluid is the fluid surrounding the cells.
  • The blood never comes into contact with the cells.
  • The blood and interstitial fluid exchange material, and the interstitial fluid then exchanges material with the cells.

Veins

  • The intricate networks formed by the capillaries eventually converge to form venules, (small veins)
  • The venules then converge to form veins which return the blood to the heart.
  • Veins only consist of two layers.
  1. The outer layer is made up of connective tissue
  2. The inner layer is made up of endothelial cells.

Valves

  • Once the blood has passed through the capillaries very little blood pressure remains to return blood to the heart.
  • Instead of pressure from the heart veins use a series of valves to force blood to return to the heart.
  • Contraction of the muscles squeezes the veins, pushing the blood through them.
  • The valves cause the blood to flow in only one direction, back to the heart.

Questions & Answers

what is mutation
Janga Reply
what is a cell
Sifune Reply
how is urine form
Sifune
what is antagonism?
mahase Reply
classification of plants, gymnosperm features.
Linsy Reply
what is the features of gymnosperm
Linsy
how many types of solid did we have
Samuel Reply
what is an ionic bond
Samuel
What is Atoms
Daprince Reply
what is fallopian tube
Merolyn
what is bladder
Merolyn
what's bulbourethral gland
Eduek Reply
urine is formed in the nephron of the renal medulla in the kidney. It starts from filtration, then selective reabsorption and finally secretion
onuoha Reply
State the evolution relation and relevance between endoplasmic reticulum and cytoskeleton as it relates to cell.
Jeremiah
what is heart
Konadu Reply
how is urine formed in human
Konadu
how is urine formed in human
Rahma
what is the diference between a cavity and a canal
Pelagie Reply
what is the causative agent of malaria
Diamond
malaria is caused by an insect called mosquito.
Naomi
Malaria is cause by female anopheles mosquito
Isaac
Malaria is caused by plasmodium Female anopheles mosquitoe is d carrier
Olalekan
a canal is more needed in a root but a cavity is a bad effect
Commander
what are pathogens
Don Reply
In biology, a pathogen (Greek: πάθος pathos "suffering", "passion" and -γενής -genēs "producer of") in the oldest and broadest sense, is anything that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a germ. The term pathogen came into use in the 1880s.[1][2
Zainab
A virus
Commander
Definition of respiration
Muhsin Reply
respiration is the process in which we breath in oxygen and breath out carbon dioxide
Achor
how are lungs work
Commander
where does digestion begins
Achiri Reply
in the mouth
EZEKIEL
what are the functions of follicle stimulating harmones?
Rashima Reply
stimulates the follicle to release the mature ovum into the oviduct
Davonte
what are the functions of Endocrine and pituitary gland
Chinaza
endocrine secrete hormone and regulate body process
Achor
while pituitary gland is an example of endocrine system and it's found in the Brain
Achor
what's biology?
Egbodo Reply
Biology is the study of living organisms, divided into many specialized field that cover their morphology, physiology,anatomy, behaviour,origin and distribution.
Lisah
biology is the study of life.
Alfreda
Biology is the study of how living organisms live and survive in a specific environment
Sifune
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Source:  OpenStax, Siyavula: life sciences grade 10. OpenStax CNX. Apr 11, 2012 Download for free at http://cnx.org/content/col11410/1.3
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