In some neurons specialized for rapid signal conduction, the axon is encased in a myelin ______________ that is interrupted at intervals.

Crabs walk using ______________ to pull themselves along.

Contraction of the ______________ tibia muscles straightens out the leg and sends the insect into the air.

A fossil snake with legs has ______________ on the evolution of snakes, which are descended from lizards that gradually became more and more elongated with simultaneous reduction and eventual disappearance of the ______________.

Translate the text into Russian orally

Мышечная активность - это одно из общих свойств высокорганизованных живых организмов. Вея жизнедеятельность человека связана с мышечной активностью. Независимо от значения, особенностей строения и способов регуляции принцип работы различных мышц организма одинаков.

Мышечная клетка отличается от других возбудимых клеток таким специфическим: свойством, как сократимость, то есть способность генерировать механическое напряжение и укорачиваться. Кроме того, мышцы являются генератором тепла причем не только при мышечной работе, холодовой дрожи, но и в режиме нетонического термогенеза.

Мышечная активность и процессе жизнедеятельности обеспечивает работы отдельных органов и целых систем: работу опорно-двигательного аппарата, легких, сосудистую активность, желудочно-кишечного тракта., сократительную способность сердца. Нарушение работы мышц (например, определяющих функционирование легких, сердца) может приводить к патологиям, а ее прекращение – даже к летальному исходу.

Мышечная ткань представляет собой совокупность мышечных клеток (волокон), внеклеточного вещества (коллаген, эластин и др.) и густой сети нервных волокон и кровеносных сосудов. Мышцы по строению делятся на: гладкие – мышцы кишечника, стенки сосудов, и поперечно-полосатые. – скелетные, мышцы сердца. Независимо от строения все они имеют близкие механические свойства, одинаковый механизм активации к близкий химический состав.

Energy Exchange

The fundamental interaction of biophysical ecology is energy exchange. Energy may be exchanged as stored chemical energy, heat energy, radiant energy, or mechanical energy. Our attention will be focused primarily on the transport of heat and radiation.

Four modes of energy transfer are generally recognized in our common language when we talk of the "hot" sun (radiative exchange) or the "cold" floor tile (conduction), the "chilling" wind (convection), or the "stifling" humidity (reduced latent heat loss). An understanding of the principles behind each of these processes will provide the background needed to determine the physical suitability of a given environment for a particular organism.

The total heat content of a substance is proportional to the total random kinetic energy of its molecules. Heat can flow from one substance to another if the average kinetic energies of the molecules in the two substances are different. Temperature is a measure of the average random kinetic energy of the molecules in a substance. If two substances at different temperatures are in contact with each other, heat is transferred from the high-temperature substance to the low by conduction, a direct molecular interaction. If you touch a hot stove, your hand is heated by conduction.

Heat transport by a moving fluid is called convection. The heat is first transferred to the fluid by conduction; the bulk fluid motion carries away the heat stored in the fluid. Most home heating systems rely on convection to heat the air and walls of the house.

Unlike convection and conduction, radiative exchange requires no intervening molecules to transfer energy from one surface to another. A surface radiates energy at a rate proportional to the fourth power of its absolute temperature. Both the sun and the earth emit radiation, but because the sun is at a higher temperature the emitted radiant flux density is much higher for the surface of the sun than for the surface of the earth. Much of the heat you receive from a campfire or a stove may be by radiation and your comfort in a room is often more dependent on the amount of radiation you receive from the walls than on the air temperature.

Define the words

The background, humidity, chilly, stifling, convection, to emit.

Complete the sentences

1. Energy may be exchanged as…

2. Our attention will be focused primarily on…

3. An understanding of the principles behind each of these processes…

4. The total heat content of a substance..

5. If two substances at different temperatures…

6. Unlike convection and conduction, radioactive exchange…

7. Both the sun and the earth…

Put the following words and word combinations into the gaps

emits / humidity / latent heat loss / density / average / transport / flux / random

The food sources used by bees tend to occur in patches, and each patch offers much more food than a single bee can ______________ to the hive.

The rate of transpiration depends on weather conditions like ______________ and the time of day.

______________ increases with air temperature in almost a linear fashion until 25ºC and then becomes increasingly high as the ambient temperature rises above 27ºC.

The necessary promoter is located within a transposable element that jumps at ______________ from one position to another within the cluster, transcribing a different surface protein gene with every move.

Tropical songbirds typically lay a clutch of 2 or 3 eggs, on ______________.

As a bat flies, it ______________ a very rapid series of extremely highpitched “clicking” sounds well above our range of human hearing.

Consequently, eukaryotic genomes have been in a constant state of ______________ during the course of their evolution.