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3 years ago

Clear-cutting ________.

1 answer:

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The answer is D. It is used to promote the growth of particular species of plants in the forests, especially species that are smothered by the little light at the ground of the forest due to blockage of sunlight by the tree canopy. After clear-cutting, there is usually an increase in plant biodiversity and mass especially due to spurred growth of bryophytes.

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As a student, what steps can you take to reduce the amount of waste you make?

creativ13 [48]

Recycle as much as you can.
turn in old pills and medications. 
brick your home so no paint residue comes off. (lead paint residue, limestone, etc.) 
collect rain off your roof into rain barrels, use in garden as needed. 
create a rain garden to prevent runoff from your lawn into the sewer. 
use collection services to recycle oil and grease. 
minimize the amount of cleaners used in your home (use more baking soda and salt) 
compost food waste and newspaper with a worm farm 
compost leaves and grass clippings in a back yard bin to grow your own food. 
mix the compost into your garden so you do not need to buy chemicals 
plant and harvest your own food, recycle again. 
bury your small pets in your own back yard 
stay healthy so you do not have to take medicines that end up in the toilet. 
start the list over again.

7 0

3 years ago

Read 2 more answers

If its _____________ in the Northern Hemisphere, then its Summer in the

Ann [662]

Answer:

winter

Explanation:

I think it is winter. yeah winter

6 0

3 years ago

Read 2 more answers

Which characteristics describe the troposphere? Select two options.

kiruha [24]

Answer:

its a and c

Explanation:

8 0

3 years ago

What effect do high temperatures have on enzymes?

adelina 88 [10]

When temperature is increased, molecules come together more frequently and with greater energy. Because chemical reactions need a certain amount of energy to occur, increasing the energy of the molecules involved in the reaction can speed up the rate at which the reaction occurs.

6 0

3 years ago

List all the electrical and mechanical events that occur within 1 heartbeat (in order). Also be able to state which are occurrin

eimsori [14]

Answer:

Phases of the Cardiac Cycle are Diastole and Systole

Explanation:

<h2>Cardiac Cycle Phases </h2>

(First Phase) Atrial contraction

This is the phase of atrial contraction.

In this fase, 80% of ventricular filling has been done passively even before the onset of atrial contraction, and the remaining 20% of ventricular filling is due to atrial contraction. The active filling of ventricles becomes valuable during physical activity.

When pressure in the atrium increases, blood rush into the ventricles through the opened mitral valve. During left atrium contraction, pressure and volume are transferred into left ventricle through opened mitral valve. Aortic valve is closed because pressure in aorta is greater than the pressure in left ventricle at this moment.

(Second Phase) Isovolumetric Contraction

The early phase of ventricular systole. When ventricles contract, there is a progressive increase in intraventricular pressure. This wil leads to closure of mitral valve. That produces first heart sound (S1) and little bulging of mitral valve into atrium causing the slight increase in the atrial pressure.

Intraventricular pressure progressively increases upto 80mmHg altought it is not competent enough to open the aortic valve.

At this moment ventricle is contracting with closed mitral and aortic valves. Meanwhile, intra atrium pressure is gradually increasing due to accumulation of blood returning from lungs into the left atrium. During the same phase, aorta pumps whatever blood it contains into more peripheral part of arterial tree due to its elastic nature.

This is the stage of ventricular contraction when backward valves are closed yet the forward valves are not opened. Ventricle is contracting as a closed chamber without any change in volume and size of the ventricle. We call it isovolumetric contraction of early part of ventricular systole.

(Third Phase) Rapid Ventricular Ejection

When pressure reaches to 81mmHg, aortic valve opens. This starts third phase of cardiac cycle. Ventricles keep on contracting, and there is a progressive increase in intraventricular pressure upto 120mmHg. During this phase, aortic valve opens and blood is ejected quickly into the aorta. At this point left ventricle and aorta behave as a single chamber.

The pressure changes occurred in the ventricles results in the transmission of pressure to aorta. Meanwhile left atrium continues receiving blood from the lungs.

(Fourth Phase) Slow Ventricular Ejection

In this phase atrium is still behaving as reservoir of blood and the pressure is keep on building. Mitral valve is closed. Ventricles are still contracting but intraventricular pressure starts falling, due to ejection of blood . Hence, pressure in aorta also starts falling, but intraventricular pressure is still more than aortic pressure.

Aortic valve remains open leading to slow ejection of blood into aorta. Elastic aorta keeps on squeezing the blood and pumps it into peripheral arterial tree.

(Fifth Phase) Isovolumetric Relaxation

In this phase ventricles start relaxing. Intraventricualr pressure falls quickly. In the beginning, as soon as the ventricular pressure becomes less than pressure in aorta, aortic valve closes.

Even though pressure in ventricle is falling, it is still high enough compared to pressure in atrium. Ventricle is relaxing with closed valves and it is known as isovolumetric relaxation. During this phase atrium is still behaving as reservoir of blood.

(Sixth Phase) Rapid Passive Ventricular Filling

When left ventricle start relaxing, pressure in left ventricle start dropping until it reaches the point where pressure in the ventricle becomes less than the pressure in atrium, leads to opening of mitral valve. Blood which was previously accumulated in atrium will rush into ventricle. This quick filling is done without atrial contraction.

(Seventh Phase) Slow Passive Ventricular Filling

As atrioventricular valve open, blood coming to atrium rushes into the ventricle. Here atrium is not acting as reservoir.

7 0

3 years ago