HELP ME Flashcards
systematics:
the disciple (under Linnaeus’s goal) that attempts to classify life. He first grouped them into things called genera
Taxonomy:
systematic classification and naming of organisms like Linnaeus’s system.
genus name:
written first, capitalized
Species Name:
first and second, second is never capitalized. When handwriting, underline both words please
Phylogenetics:
classifying organisms based on their evolutionary relationships
cladistics:
every defined taxon must contain the species ancestral to that group plus all the species descendants.
the biggest taxon of all
life
equal clades:
same number of branches off of each one
molecular differences:
differences in proteins reflect the time since a common ancestor. more recent common ancestor has less protein differences.
evolution happens to
populations
natural selection happens to
individuals
environment does
selecting
each generation takes
the best of the last generation and varies it in the next generation
evolution does not
predict the future, organisms adapt to past environmental conditions
we are not a blend of
our parents, we are a new set of factors made from the subsets of our parents’ factors.
why does the phenotypic ration not exactly reflect the punnett square prediction?
Because probability has no memory and everything is chance. Always write approximately for all answers
when do unfavourable alleles stay in population?
When they persist for long periods without being exposed frequently in recessive phenotypes
genetic drift:
results in evolution that is nonadaptive. al id does is overrepressent an allele in population by chance alone
punnett square communication:
dominant always goes before recesive, maintain consistency with other dominance types, males are always written at the top of the punnett square, identify all the phenotypes and don’t forget to write parents into corner of square
when asking for “gametes that this can produce”:
state things that you would put in a punnett square ex. AA can only produce A gamete.
adaptation:
a trait that gives an individual an advantage in its environment or the process by which a population acquires such a trait due to natural selection
hardy Weinberg equilibrium:
shows the genotypes of a population where the frequencies don’t change. this is equilibrium.
doing hardy Weinberg equilibrium problems:
remember to convert the frequencies into number of individuals and vice versa, always write approximately!!!
conditions of hardy Weinberg
no mutations, no genetic drift, no gene flow, random mating and no selection
evolutionary adaptation
Organisms produce more offspring than the resources can support, leading to competition. Offspring resemble but differ from their parents and from each other, so some are better at competing than others. Provided the traits are heritable, the favourable traits will increase in the population, while the less favourable ones will disappear over time. the result is evolutionary adaptation.
coronary arteries
The first branches from aorta are the coronary arteries, which supply blood to the myocardium. They can become clogged and can cause angina pectoris or even a heart attack (myocardial infarction)
P wave:
atria are excited (signal starts at top of atria)
QRS
ventricular excitation (signal goes down septum and partially up the ventricles)
T wave:
end of ventricular excitation (signal travels up to the top of ventricles)
beginning of cardiac cycle:
atria and ventricles are relaxed. AV valves are open, SL valves are closed. Atrial depolarization triggers atrial contraction. There is low aortic pressure, low left ventricle and atrial pressure here.This is part of P wave.
atrial contraction:
atria contract which causes the atrial pressure to rise. it pushes blood into the ventricles, raising the ventricular pressure slightly. ventricular excitation triggers ventricular contraction. this is from half of P to Q and R. Signal travels to atria. Ventricular volume slightly increases.
Isovolumetric Contraction:
Signal goes down the septum and partially up the ventricles. Blood volume and muscle cell length do not change at first. Ventricular pressure rises above the atrial pressure forcing the AV valves closed. Ventricular pressure continues to rise. This is S of QRS wave
Ventricular ejection:
ventricular pressure rises above arterial pressure. Semilunar valves open. Blood is ejected into arteries, decreasing ventricular volume. ventricular repolarization (T wave) marks the end of ventricular contraction. aortic pressure is highest, left ventricle pressure is highest and left atrial pressure is low.
Isolvolumetric relaxation:
Repoarlization of ventricular muscle cells triggers this. ventricles relax, ventricular pressure drops and semilunar valves close preventing blackflow. All valves are closed so blood volume does not change. As the ventricle relaxes, the ventricular pressure falls quickly. End of t wave.
Passive ventricular filling:
all four chambers are relaxed, AV valves are open. ventricles fill from blood from atria. blood volume increases a lot. Atria depolarization which triggers atrial contraction forcing a small amount of extra blood into ventricles and new cycle begins. (this is the flat part to the half of the new p wave.
LUBB:
after closure of AV valves. Marks the start of ventricular systole.
DUBB:
follows closure of Semilunar valves. marks the start of ventricular diastole.
how are leukocytes different from white blood cells:
they have a nucleus, not iron or hemoglobin and only live for a few days. Most common is neutrophylls
Clotting:
platelets first congregate and form a plug. The damaged wall of the blood vessel and platelets release the protein thromboplastin and calcium ions. A series of chemical reactions starts and the final step in these reactions is the conversion of plasma protein prothrombin into thrombin. Platelets and damaged tissue cells release an enzyme called prothrombin activator which initiates a cascade of enzymatic reactions. Fibrin threads form and trap red blood cells.
Why would you have multiple steps to a cascade reaction?
More control, enzymes can be used again, not destroyed (efficiency) and if you have a weak signal, you can amplify it if need be.
lymph nodes only occur
in mammals
lymph nodes become swollen
during active production of lymphocytes
lymph vessels
lymph vessels are found in all vertebrates.Some propel the system through lymph hearts, others depend on forces from other body parts or gravity
things to remember about lymph system:
occurs in closed circulatory systems, the diameter of blood and lymph capillaries is large enough to allow passage of blood cells, lymph vessels are closed tubes (one way flow).
What stays in capilaries vs what goes to cells:
Red blood cells, proteins, wastes and co2 remain in capillaries while white blood cells, water, salts, nutrients oxygen all diffuse into cells. lymph then collects white blood cells, water salts and wastes.
bronchial arteries:
part of systemic circuit and provides oxygenated blood to the lungs themselves.
systole:
when the heart is NOT doing work. the pressure is low.
Diastole:
When the heart IS doing work. Pressure is high
Pacemaker:
The SA pacemaker is a cluster of cardiac cells that discharges spontaneously at about 60-70 times per minute. It initiates the contraction of the muscles in the atria, starting a wave that spreads over the entire heart muscle. In this way, it controls the heart rate. The pacemaker can be adjusted by signals from nerves that originate in the brain. One set of nerves releases epinephrine (adrenalin) and speeds up the pace maker. The other releases acetylcholine and slows down the pacemaker.
The AV node acts as a secondary pacemaker. It will cause the ventricles to beat at about 40 beats per minute, even if the SA node fails.
pulmonary loop:
goes to the lungs only
systemic loop
all parts of body (even supplies blood to lungs)
Describe the blood plasma:
Plasma consists of water with about 7% dissolved proteins (mostly albumin, but significant amounts of antibodies, carrier proteins, clotting proteins, etc.). It is salty, with about half the salinity of sea water (mostly sodium, chloride, potassium, calcium, phosphate, etc.) and has dissolved nutrients (glucose, amino acids, oxygen) and wastes (CO2, ammonia, urea)
What are some of the proteins in plasma and what do they do?
albumin – provides viscosity Clotting proteins – participate in formation of clots
immunoglobins (antibodies) – provide specific immunity
carrier proteins – transport insoluble substances like fats, cholesterol
red blood cells:
erythrocytes, found in bone marrow. carry oxygen and some co2 and specialized protein haemoglobin
white blood cells:
Leukocytes, found in bone marrow, lymphocytes mature in thymus and lymph nodes. they provide non-specific and specific immunity. specialized proteins include immunoglobins (antibodies, histamine, interleukins (signal molecules to other WBCs).
Platelets:
thrombocytes. found in bone marrow→ cells pragment in blood stream. They block cuts and initiate clotting response. specialized proteins are the clotting factors that initiate a cascade of enzyme reactions in the plasma.
granular cells that phagocytize foreign cells are called
neutrophils
agranular cells that migrate outside the blood and ingest foreign cells are called
monocytes
cells that induce allergic responses are called
eosinophils and basophils
white blood cells that produce antibodies to fight disease organisms are called
lymphocytes.
How does water potential differ at the beginning and end of a capillary? (Water potential is the net effect of osmotic pressure and physical pressure on water movement.)
The blood in the capillaries is hypertonic to the tissue fluid because plasma proteins remain in the blood as solutes, so there is always osmotic pressure pulling water back into the capillary (⎠s). Blood pressure is high at the beginning of the capillary pushing fluids out of the blood (high ⎠p) but drops by the end (low ⎠p). Fluid leaves the capillary at the beginning (net ⎠ outward) but is drawn in at the end (net ⎠ inward)
What is the main purpose of the lymphatic system?
To recover fluids lost from the blood. other purposes include to absorb fats from the digestive tract and to help defent the body from disease (lymphoid organs).
blood pressure:
Blood pressure is the amount of force applied to a given area of a blood vessel wall as the blood flows past it
why do capitallries have such less pressure and velocity?
Good for diffusion into cells. also, it is because capillaries have a greater total cross sectional area that arterioles.
arteries:
have no accessory structions, carry high pressure blood away from ehart, have high and pulsing blood pressure which is controlled by the actions of the heart. the oxygenation of the arteries depends on whether it is pulmonary or systemic (low, high)
capillaries:
have precapillary sphincters and AV shunts. they deliver resources (oxygen and nutrients) and pick up wastes. Blood pressure is dropping with no pulse and is controlled by heart. oxygenation depends on whether it is pulmonary or systemic (declining, increasing)
veins:
have valves and muscles to direct flow of the blood. They carry low pressure blood back to heart. The pressure is low with no pulse and the source of the pumping action is the surrounding muscles. oxygentation depends on whether it is pulmonary or systemic (high, low).
lymphatic ducts:
accessory structures are valves to direct flow of lymph. they return fluid lost from capillaries and there is no pressure. the source of the action is the surrounding muscles and the oxygenation depends on whether it is pulmonary or systemic (low, high).
how is blood moved back to the heart?
Skeletal muscles squeeze on the veins, generating pressure. The one way valves in the veins prevent the blood from moving backwards, while the muscular pressure pushes the blood towards the heart. The most important movements in keeping the blood moving toward the heart are the movements of breathing, which change the pressure on the posterior vena cava and pump blood uphill from the lower body. (Of course, blood from the upper body can use gravity as well to flow back to the heart.)
criteria for a specialized gas exchange system to meet the needs of a large organism
1) large moist surface area since oxygen will only diffuse if it is able to dissolve in water. it is mostly protected inside the body since the surface will dry out
2) ventilation must occur to bring outside air in contact with the system.
3) must be an efficient pick up, transport and delivery system
4) thin because the diffusion distance is short
Surface area and lungs
Anatomy of the system is designed to have large SA for limited volume.
Cohesion tension model
- Transpiration (water loss) at leaves
- Tension in water column extends from leaves to roots.
- Water + minerals are pulled through the xylem vessels
- More absorption happens in roots
Factors That Increase Transpiration
• dry air (low humidity)
• wind
• high temperatures
high number of stomata
