Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Human Biology > Week 7 Circulatory system > Flashcards

Week 7 Circulatory system Flashcards

1
Q

Pericardium

A

Covering of the heart

  • Outer fibrous sac
  • inner serous layer (secretes slippery fluid to prevent friction
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Epicardium

A
  • Thin layer of connective tissue
    -Contains fat
    -
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Myocardium (muscle heart)

A
  • Thick cardiac muscle walls

- cardiomyocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Cardiac muscle build

A
  • Striated
  • Involuntary
  • Branched
  • 1-2 Nuclei
  • intercalated discs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Endocardium (inside the heart)

A
  • Innermost surface that lines heart chambers
  • Endothelium continuation of blood vessels
  • Simple squamous epithelium (flattened)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Chamber of the heart

A
  • Left and right Atria
  • Left and right Ventricles
  • Cardiac septum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The atria

A 
(Atrium = entryway)
Are receiving chambers
• Relatively small, thin walled
• Minimal contraction
Right Atria
• Blood enters via 3 veins:
• Superior vena cava
• Inferior vena cava
• Coronary sinus
Left Atria
• Blood enters via 4 pulmonary
veins
• Fossa ovalis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

The ventricles

A 
(ventr = underside)
• Discharging chambers ie pumps• Majority of heart volume• Trabeculae carneae
Right Ventricle
• To pulmonary trunk
Left Ventricle
• to body via aorta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Patent ductus arteriousus (PDA)

A

The ductus arteriosus is a normal foetal blood vessel that closes soon after birth
• vessel does not close a• remains “patent“
• irregular mixing of oxygenated and deoxygenated blood
between two of the most
important arteries
• the aorta
• pulmonary artery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Valves of the heart

A 
Atrioventricular (AV)
Valves
Cuspid = pointed
• Right: tricuspid (3 cusps)
• Left: bicuspid/Mitral (2 cusps)

Semilunar (SL)valves
• Semilunar = half moon
• Right: pulmonary valve
• Left: aortic valve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Cardio-Pulmonary Circulation

A 
RIGHTSIDE:
Vena cavae (blood from body)
Right atrium
Right ventricle
Pulmonary artery (blood to lungs)
LEFT SIDE:
Pulmonary vein (blood from lungs)
Left atrium
Left ventricle
Aorta (blood to body)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Intrinsic

Conducting System

A 
Sinoatrial (SA) Node
• Electrical pace maker
Atrioventricular (AV) Node
• Receives impulses from SA
Node
Atrioventricular (AV) Bundle
• Bundle of HIS
• Electrical link between atria
& ventricles
Subendocardial conducting
network
• Purkinje Fibres
• Distribute impulses to
ventricles
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Cardiac Pacemaker Cells

A 
Autorhythmic
• Have the ability to spontaneously
depolarise
• Contain special cell membrane ion
channels
• Are distributed throughout the
intrinsic conducting system
• “Fastest” cells located in SA node
(75-100bpm)
• The SA node sets the initial pace
(called the “pacemaker”)
• Ectopic pacemaker (25-40bpm)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

The Electrocardiogram (ECG)

A

Shows currents arising from electrical activity of heart
• Recorded by electrodes placed on skin
• Size and shape varies
with electrode position• Basic features: P wave, QRS complex and T wave

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The Cardiac cycle

A 
Describes timings and mechanical
events associated with blood flow
through the heart that follow the
electrical events
Systole:
• Period of ventricular contraction
• Blood ejected from heart
Diastole:
• Period of ventricular relaxation
• Blood filling ventricles of heart
Blood pressure: Systolic/Diastolic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Heart function measures

A 
Two different metrics:
• Blood Pressure (BP)
• Pressure created by the
cardiac cycle
• Measured in mm Hg
1• Heart Rate (Pulse)
• The number of
cardiac cycles per
time
• Beats per minute
(bpm)
17
Q

Regulation of blood pressure

A

Goal is to ensure appropriate tissue perfusion• Short-term
• Alter peripheral resistance & cardiac output
• Hormonal control
• Eg adrenal medulla hormones (epinephrine,
norepinephrine), angiotensin II, atrial natriuretic peptide & antidiuretic hormone (ADH)
• Long-term
• Alter blood volume
• Renal mechanisms

18
Q

Regulation of Heart Rate:

Neural & Chemical

A 
Autonomic Nervous System
• Sympathetic nervous
system (norepinephrine)
Hormones
• Epinephrine (adrenaline)
• Thyroxine
• Directly effects heart
• Enhances effects of
epinephrine
Ions
• Particularly Ca2+ and K+
19
Q

Blood vessel structures

A

Consist of 3 layers (tunica)
• Tunica interna (tunica intima): thin endothelium• Tunica media: middle, smooth muscle layer
• Tunica externa (tunica adventitia): fibrous
connective tissue

20
Q

Arteries vs Veins

Comparison of wall structures

A 
Arteries
• Thick tunica media
(smooth muscle) walls
• Contain layers of elastin
fibres (elastic laminas)
• No valves present
Veins
• Relatively thinner walls
(thinner tunica media)
• Very little elastin fibres
• Valves present to
prevent backflow of
blood
• More fibrous outer layer
21
Q

Major Arteries of the Human Body

A

Major Arteries• Aorta• Coronary
Artery• Common
Carotid Artery

22
Q

Vasodilation

A 
Widening of the lumen of a blood vessel
due to relaxation of the smooth muscle
within the tunica media
• Increases blood flow to the tissue
• Controlled by sympathetic nervous system
23
Q

Vasoconstriction

A 
Reduction in the lumen
diameter of a blood vessel
due to contraction of the
smooth muscle within the
tunica media

Decreases blood flow to the tissue
• Controlled by
sympathetic nervous system

24
Q

3 basic capillary types

A

Capillaries are:
Site of exchange between blood and tissues
• Single endothelium layer and basement membrane

Continuous
Fenestrated
Sinusoid

25
Q

The lymph nodes

A
  • Two functions
  • Cleansing the lymph
  • Immune system activation
26
Q

Lymph node structure

A

capsule
fibrous
• trabeculae

cortex
densely packed follicles,
• germinal centres
• packed with dividing B
lymphocytes
• T cells in transit move
through the deeper cortex

medulla
contains sinuses
• spanned by reticular fibres on
which macrophages reside

27
Q

The spleen

A

Sits under the left side of the stomach
• Site for: – lymphocyte proliferation/immune surveillance
– storage of breakdown products of RBC’s
– storage of blood platelets (for clotting)
– reservoir for blood

28
Q

The thymus

A 
Glandular lymphoid structure
• Located above the heart
• Site for T-lymphocyte maturation
- secretes hormones (thymopoietin and thymosin) to activate T-lymphocytes
in an immune response
29
Q

The tonsils

A 
Four (4) sets of tonsils found in the human throat:
1. palatine tonsils
- either side at back of throat
2. lingual tonsils
- at base of tongue
3. pharyngeal tonsils (adenoids)
- back of nose
4. tubal tonsils
- around openings of the auditory tubes (Eustachian tubes) into
the back of throat

Human Biology (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions