Genes and health + Voice of the genome Flashcards
1
Q
what are the 4 main components of blood?
A
- plasma
- platelets
- white blood cells
- red blood cells
2
Q
what is an open circulatory system?
A
where blood is pumped by the heart into body cavities, where tissues are surrounded by blood
3
Q
what is a closed circulatory system?
A
where the blood always stays in the vessels and never directly contacts cells
4
Q
what is a single circulatory system?
A
where the blood flows through the heart once per cycle
5
Q
what is a double circulatory system?
A
where the blood flows through the heart twice per cycle
6
Q
name 3 advantages of a double circulatory system?
A
- pressure can be maintained
- cells have a high metabolic rate
- prevents the mixing of blood, so the o2 content stays high
7
Q
what is mass transport?
A
the bulk movement of gases or liquids in 1 direction
8
Q
name 4 things needed for a mass transport system?
A
- a system of vessels
- a way of making sure substances movwe in the right direction
- means of moving materials
- a transport medium
9
Q
name 3 benefits of mass transport?
A
- move substances quicker
- maintains concentration gradients
- ensures effective cell activity
10
Q
what is a pulmonary circuit?
A
blood moving from heart to lungs
11
Q
what is a systemic circuit?
A
blood moving from the heart to the body
12
Q
what does the umbilical artery do?
A
takes blood from the feotus to the placenta
13
Q
what is the order of blood vessels?
A
arteries - arterioles - capilleries - venuoles - veins
14
Q
what is collagen?
A
connective tissue
15
Q
where are veins situated and what does this do?
A
near large muscle groups, so when they contract they squeeze the veins, helping maintain pressure
16
Q
what do valves do?
A
keep blood flowing in the right direction
17
Q
name 2 reasons that mass transport is better than diffusion?
A
- faster
- transports substances over longer distances
18
Q
name the 5 main functions of blood?
A
- transports excretary products
- transports digested food
- transports hormones
- maintains body temp
- buffer to PH changes
19
Q
how many binding sites does a heamoglobin molecuole have?
A
4
20
Q
what is special about heamoglobins cytoplasm and why?
A
it has low oxygen levels, to maintain a steep gradient
21
Q
what does high oxygen affinity mean?
A
binds easily, dissociates slowly
22
Q
what does low oxygen affinity mean?
A
binds slowly, dissociates easily
23
Q
what does partial pressure of oxygen mean?
A
oxygen concentration
24
Q
if a partial pressure graph shifts to the right what does that mean?
A
lower oxygen affinity, so it dissociates easier
25
if a partial pressure graph shifts to the left what does that mean?
higher oxygen affinity, so oxygen loads easier in the lungs
26
what partial pressure shift should a small/active organism have?
right
27
what is the name fore heamoglobin that has binded to C02?
Carbiminiheamoglobin
28
what percentage of CO2 is carried by plasma?
5%
29
what percentage of CO2 is carried in heamoglobin?
10 - 20%
30
how is most CO2 in the body stored?
it reacts with water to form carbonic acid, with the help of the enzyme carbonic anahydrase
31
what happens to CO2 in the lungs?
the reaction is reversed and CO2 diffuses out into the lungs
32
what does carbonic acid separate into?
H+ ions and hydrogencarbonate ions
33
name 2 reasons for blood clotting?
- prevent blood loss
- prevent entry of pathogens
34
what is thrombosis?
the process of clotting
35
what is seratonin?
hormone that causes smooth muscle to contract, constricting blood vessels
36
what is thromboplastin?
an enzyme which controls formation of a clot
37
name the 4 steps of blood clotting?
1) thromboplastin catalyses the conversion of prothrombrin into an enzyme called thrombrin using calcium ions
2) thrombrin also converts fibrinogen which converts into fibrin which forms a mesh of fibres
3) more cells and platelets fall into the mesh, building the clot
4) special protiens in the platelets contract, tightening the clot
38
name the 3 types of valves?
- tricuspid valve
- bicuspid valve
- semi-lunar valves
39
how many semi-lunar valves are there?
2
40
where is the tricuspid valve located?
between the right atrium and right ventricle
41
where is the bicuspid valve located?
between left atrium and left ventricle
42
where are the semi-lunar valves located?
- between the right ventrical and pulmonary artery
- between the left ventricle and aorta
43
what do the tendonis cords do?
ensure the valves aren't turned inside out
44
what supplies blood to the heart muscle?
the coronary artery
45
what does systole mean?
hearts contracting
46
what does diastole mean?
heart is relaxed
47
what is a cardiac cycle?
1 sequence of filling and pumping blood in the heart
48
what type of muscle is the heart?
myogenic
49
what 4 things happen during diastole?
- atria and ventricles relax
- elastic recoil lowers the pressure
- the semi-lunar valves close
- veins draw blood into the atria
50
what happens during atrial systole?
the atria contract, forcing blood into the ventricles
51
what happens during ventricular systole?
the ventricles contract, pushing blood out the heart
52
what does myogenic mean?
it initiates its own contractions
53
name the 2 nodes that control the cardiac cycle?
- sinoatrial node
- atrioventricular node
54
where is the sinoatrial node?
above the right atrium
55
where is the atrioventricular node?
near the atrioventricular valve
56
name the 6 steps of a full cardiac cycle?
1) SAN sends out a wave of electrical excitation
2) atria contract, blood flows through tricuspid valve
3) after a short delay, the AVN sends out a wave of electrical excitation
4) then the "bundle of his" transfers the signal don to the septum
5) then, the impulses are conducted by purkinje fibres
6) ventricles contract from the base, upwards so blood leaves the heart
57
name 3 things that affect pressure in the heart?
- contractions
- filling with blood
- state off valves
57
name 3 things that affect pressure in the heart?
- contractions
- filling with blood
- state off valves
58
why do valves open?
to allow movement of blood into a certain area
59
why do valves close?
to prevent the backflow of blood
60
what is the equation for stroke volume?
cardiac output X heart rate
61
how does caffiene work?
stimulates production of noradrenaline by inhibiting release of adenosine, this triggers an increase in heart rate , meaning blood is pumped faster and oxygen is delivered to muscle and brain tissue at a higher rate.
62
what is noradrenaline?
a neurotransmitter usually released during “fight or flight” situations
63
what is adenosine?
a depressant
64
what are daphnia?
aquatic crustaceans
65
what is atheroma?
fatty deposit in the arterys
66
what is an endothelium?
inner cell lining of blood vessels
67
what is athlerosclerosis?
a disease affecting blood vessels, causing CVD and strokes.
68
what are the 6 steps of athlerosclerosis?
1) endothelium is damaged
2) inflammatory response is caused
3) atheroma builds up
4) plaque forms due to calcium salt and fibrous tissue deposition
5) as a result, the artery stiffens
6) positive feedback occurs, causing more inflamation
69
what is epidimiology?
the study of people, patterns, causes and effects of diseases
70
what is the calculation for blood pressure?
force / SA of vessel
71
how does salt affect blood pressure?
it increases water retention in the blood, increasing blood pressure
72
what does hypertension mean?
high blood pressure
73
how do you present blood pressure?
systolic pressure / dystolic pressure
74
name 6 treatments for CVD?
- ACE inhibitors
- calcium channel blockers
- diuretics
- statins
- anticoagulants
- platelet inhibitors
75
what do ACE inhibitors do?
relax veins and arteries to lower blood pressure
76
what do calcium channel blockers do?
prevent calcium entering artery walls, weakening contractions
77
what do diuretics do?
prevents build up of water in the blood, lowering blood pressure
78
what do statins do?
lower LDL cholesterol levels
79
what do statins do?
lower LDL cholesterol levels
80
what is the function of the nucleolus?
dark spot in the middle of the nucleus, site of ribosome formation
81
what is the function of the nuclear envelope?
Transports RNA and protiens in and out of the nucleus
82
what is the function of the amyloplast?
energy store
83
what is the function of the plasmodesmata?
connects cytoplasm of neighbouring cells, allows substance transport
84
what is the function of the golgi body?
modifies protiens and lipids
85
what is the function of the tonoplast?
vacule membrane, regulates ion movement
86
what is the function of the middle lamella?
cement layer between plant cells
87
what is the function of the smooth ER?
makes lipids and steroids
88
what is the function of the rough ER?
produce proteins
89
what valves open and close during diastole?
- SL valves are closed
- AV valves are open
90
what valves open and close during atrial systole?
- AV valves are open
- SL valves are closed
91
what valves are open during ventricular systole?
- AV valves are closed
- SL valves are opened
92
what is a transcription factor?
protiens that bind to DNA and regulate gene expression
93
where can transcription factors bind?
promoter region
enhancer region
94
what does a promoter region do?
increase transcription
95
what does an enhancer region do?
decreases transcription
96
what is an operon?
unit of linked genes that regulate protien synthesis
97
what is a repressor protien?
prevents transcription when activated
98
how does a repressor deactivate in ecoli?
lactose binds to it to remove it by changing its shape
99
what is a promoter?
starting point for transcription
100
what is an operator?
binding site of repressor
101
what is epigenetics?
genetic control by factors other than DNA sequence
102
what are the 2 main method for epigentics?
- histone modification
- DNA methylination
103
what is Histone modification?
when DNA is tightly wrapped around the histone transcription is much harder, and vise versa
104
what is DNA methlynation?
adds a methal group to DNA at a CPG site, preventing transcription
105
what does sexual reproduction in plants involve?
transfer of pollen between male and female parts
106
what is the anther?
where pollen is produced
107
what is the stigma?
part of the female reproductive organ which receives pollen
108
what is the ovary?
part where female gametes are located
109
what gender produces pollen?
male
110
what happens after pollination occurs? (4 steps)
- pollen grain germinates, and a pollen tube rows down the style to the ovary
- 2 haploid male nuclei move down tube
- generative nucleus divides by mitosis to form 2 haploid male nuclei
- As the pollen tube reaches the ovule, the pollen tube nucleus breaks down and the two haploid male nuclei pass into the ovule so that fertilisation can occur
111
what are the 2 nuclei in the pollen tube called?
- pollen tube nucleus
- generative nucleus
112
whats a style?
tube-like structure in which connects stigma and ovary.
113
how do steroid hormones pass through cell membranes?
theyre lipid soluble
