Why broadleaf forest is considered a more sustainable ecosystem. Forest ecosystem Sustainability of forest ecosystems
Help please. Biology. and got the best answer
Answer from Daria Gubina[newbie]
1. Birds that eat insects nest in hollow trees. If they are cut down, insect pests will damage young trees and plants, which will lead to the gradual death of the forest.
2. Herbaceous light-loving plants develop first, then shoots of birch, aspen, pine appear, the seeds of which have fallen with the help of wind, birds, insects, a small-leaved or pine forest is formed; under the canopy of light-loving species, shade-tolerant spruce trees develop, which will subsequently completely crowd out other trees.
3. Grass emits less oxygen per m^2 of land than a tree! The grass is covered with snow in winter, but the tree still continues to fulfill its mission of releasing oxygen.
5 The food network is formed from a variety of interconnected food chains, which means that its diversity is based on the diversity of species, the presence of producers, consumers, decomposers among them and the diversity of their food (broad food specialization).
The forest ecosystem is a collection of living organisms, the main life form of which are trees. Forests occupy one third of the Earth's land area, which is 38 million km2. Half of this area is occupied by tropical, the rest by coniferous, mixed, deciduous and broad-leaved forests.
According to its structure, the forest ecosystem is divided into tiers. The height of each tier and the composition of living organisms in it depend on the species diversity of the plants that form it.
The main thing in the ecosystem as a whole and in its food chain, obviously, are the plants - producers. The remaining links of the trophic chain are consumers and destroyers of the forest ecosystem, although they play a dependent, but important role in it. And if the "activity" of consumers in all types of ecosystems is approximately the same, then the "existence and work" of destroyers is different in each type.
The coniferous forest ecosystem is formed in cold climatic conditions. The average annual temperature of this natural zone is from +5 0 С to -5 0 С. A small level of precipitation is up to 200 mm. They mostly fall in the form of snow. Winter is long. Summer is short. But daylight hours are long. Such a temperature and light regime does not allow moisture to quickly evaporate from the soil surface, and these are excellent conditions for the growth of coniferous trees.
They are distributed in North America and Eurasia. In the southern hemisphere, such forests do not form a single massif. In South America and Australia, they are found mainly in the mountains.
Another name for coniferous forest is taiga. It has many plant species, but coniferous trees dominate and occupy the top layer of the ecosystem. The needle, which in these rocks replaces the leaf, does not fall off depending on the season. Snow slides easily over it. It is “covered” from frost with a layer of resin, and a small surface allows it to tolerate cold well and give less moisture during evaporation. These trees do not stop photosynthesis even at a temperature of 0 0 C.
In the tropics, on certain types of soil, pine forests can grow. They have their own composition.
The main species are: fir, pine, spruce, hemlock and larch. Another distinguishing feature of them, in addition to needles instead of leaves, are cones. The presence of needles instead of leaves does not mean that all conifers are evergreen. There are tree species that shed their needles seasonally.
Coniferous forest ecosystems are inhabited by mosses and lichens, which, together with trees, are also producers. They not only participate in the process of photosynthesis, but also serve as a nutrient base for the next link in the food chain - consumers - animals.
The main and top of the trophic chain of this type of forest are predators, in particular, cats - tiger and lynx. There are wolves, bears, foxes and other predators. Herbivorous mammals are mainly from the deer family. There is a hare, a squirrel, a marten, a sable, a hedgehog and a tree porcupine, different types of birds.
The “work” of decomposers or destroyers in them depends on the density of crown or canopy density. There are dark coniferous and light coniferous forests. The first consist of varieties of shade-tolerant trees, which are closely closed, which is why the density of the canopy is high. This slows down the processes of processing organic substances and the formation of humus. Soils are therefore less fertile. In light conifers, sunlight penetrates the soil more easily and the processes in it go faster.
South of coniferous is mixed.
Mixed
The ecosystem of a mixed forest is a mixture of two ecosystems, due to the presence of deciduous and coniferous species in it. Thus, ecosystems complement and strengthen each other, and the resulting common becomes more stable. It is considered mixed when one type of tree is mixed with another in a volume of at least 5%. Therefore, it is no coincidence that such forests are located between coniferous from the north and broad-leaved from the south. They are mainly found in climatic zones with warm summers and cold winters. With an average annual rainfall of up to 700 mm. The soils of their growth are sod-podzolic or brown with a large amount of humus.
The natural zone of these forests is the temperate zone: the southern part of Scandinavia, the East European and West Siberian plains, the Carpathians, the Caucasus, the Far East, Southeast Asia. On the American continent - the Appalachians, the Great Lakes region and California in North America, most of South America and New Zealand.
The main tree species are: spruce, pine, oak, maple, linden, ash and elm. In the Caucasus and the Far East, beech and fir are added. In mountainous regions - larch, and in America - sequoia. Plants representing the lower tiers also have a wide species diversity.
The rich flora of mixed forests are producers and autotrophs, that is, organisms that synthesize oxygen and organic substances from inorganic substances using solar energy. They are the backbone of any ecosystem, and mixed forests are no exception.
The next stage in the food chain belongs to consumers or consumers, heterotrophic organisms. Their total mass is an order of magnitude less than the plant mass - green, which is the main rule for the viability of the ecosystem. These include: animals, birds, fish, amphibians, reptiles, insects, fungi and bacteria. It is less varied. These are: rodents - hares, squirrels, mice; mammals - deer, moose, wolves, foxes; birds - owl, woodpecker; insects - ticks, mosquitoes, spiders; protozoa - bacteria.
Close the food chain - gravediggers - destroyers or decomposers: insect larvae, worms, microorganisms.
A feature of the food chain of a mixed forest is sustainability, due to species mutual complementation and, if necessary, replacement. With a decrease in the population or the disappearance of any type of producer, it is replaced by the number of individuals of another. This rule does not apply to insects. They are pollinators of plants, and their larvae are decomposers. Their disappearance will lead to the extinction of the ecosystem.
Mixed forest ecosystems are replaced by broad-leaved ones.
In a broad-leaved forest, the ecosystem is characterized by the species diversity of deciduous or summer-green plants, that is, shedding leaves in the autumn-winter period. Their leaves have wide leaf blades. Such forests grow in humid and moderately humid climates with high temperatures. Summer is long. Winter is mild. They prefer gray, podzolic, brown or even chernozem soils. Distribution areas - Europe, North America, East Asia, New Zealand and southern Chile.
The basis of the forest and its upper tiers are: hornbeam, linden, ash, elm, maple, beech, oak and chestnut. Below are hazel, bird cherry and euonymus. "First floor" at the forest tree, gout, zelenchuk, lungwort and so on. All of these are producers.
Consumers are consumers, these are mammals such as: wild boar, deer, elk, bison, beaver, squirrel, hedgehog, fox, lynx, wolf, tiger, skunk, raccoon and brown bear. Birds: siskin, hazel grouse, nightingale, titmouse, bullfinch, capercaillie, black grouse, owl, eagle owl, stork, duck and others. Reptiles, amphibians and fish are also consumers. This is a viper, copperhead, frog, toad, salamander, catfish, pike, carp and salmon.
The decomposers or gravediggers of the broad-leaved forest are practically the same as in other ecosystems - worms, insect larvae, microorganisms.
The broadleaf forest ecosystem is also resilient and well regulated. A special feature is the period when the trees are without leaves. The process of photosynthesis stops. The "main" role goes to the decomposers, which should maximally convert organic compounds into inorganic ones.
At the equator, deciduous change tropical forest ecosystems.
In the rainforest, the ecosystem was formed on the basis of a warm tropical, subtropical and equatorial climate. They encircle the Earth at the equator. The diversity of flora and fauna is dictated solely by the amount and distribution of precipitation by season. There are forests of the humid equatorial belt and dry tropical. If the humidity is about the same throughout the year, then they are evergreen. If not, then green only in winter.
Tropical rainforests have a very diverse flora. It is dominated by trees, which can be up to 100 species per hectare. The main types of trees are: dipterocarps, legumes, myrtle and palms. Of the other types of vegetation, it is necessary to distinguish ferns that exist on different tiers of the rainforest. There are three such tiers in total. The upper one reaches 55 meters in height, the next one up to 30 and the lower one up to 20. The grasses here can reach a height of 6 meters. For example: banana. The boundaries of the tiers are blurred by plants such as creepers, epiphytes, bamboo, fern, and so on.
Terminalia, dalbergia, albizia, bamboo, teak and ebony, palm trees, laurel and sugarcane grow in seasonal deciduous forests. The main herbs are cereals. Sometimes, to retain moisture, plants are covered with thorns.
The species diversity of tropical consumers surpasses any other forests. Many animal species spend most of their time in trees. The most famous are monkeys, flying squirrels, sloths. Birds also live there - parrots, woodpeckers, toucans, hummingbirds and many others. Reptiles also live in places of maximum "accumulation" of food, that is, in trees. These are chameleons, snakes, geckos, jaguanas, agamas, and even amphibian frogs, trying to climb higher. There are not many exclusively terrestrial species of animals, but they are very large. Their main species are: elephant, rhinoceros, hippopotamus, buffalo, giraffe. Invertebrates are diverse in appearance - ants, termites, centipedes and butterflies.
Plants of the second tier usually close the canopy so tightly that they do not let in sunlight. This negatively affects the "activity" of the destroyers. In deciduous forests, there are decomposers, and these are mainly fungi and termites, which also cannot process such a huge amount of organic matter. Because tropical, with such an intensive "production" of oxygen - about 55.5 Gt per year, "preserve" in their organic matter up to 4.6 Gt of carbon dioxide.
Conclusion
A characteristic common to a forest ecosystem may be as follows. All of them are built on the basis of the dominance of the plant world over the animal world. Among plants, one or more species of trees play the main role. Depending on this, the systems are classified as single-species or mixed. An ecosystem of any kind has tiers. The amount of sunlight and oxygen penetrating into its lower tiers depends on the density of closing of tree crowns. Especially, in the layers inhabited by decomposers - destroyers. And this, in turn, affects the amount of inorganic “food” synthesized by them for the trees themselves. Ecosystems in which there is an imbalance in favor of any living organisms are not sustainable enough and can be damaged and destroyed. The most stable are forest ecosystems with a mixture of species and their interchangeability.
Video - Forest Ecosystems
PRACTICAL WORK
evolution.
- Find errors in the given text. Indicate the numbers of the proposals in which they are made, correct them.
- Find errors in the given text. Indicate the numbers of the proposals in which they are made, correct them.
- Find errors in the given text. Indicate the numbers of the proposals in which they are made, correct them.
- Using the picture, determine what form of selection it illustrates, justify it. Will the size of the ears of hares change in the course of evolution under the action of this form of natural selection, and under what conditions of life will this selection manifest itself?
Number of individuals
Sign value
PRACTICAL WORK
SOLVING ENVIRONMENTAL TASKS 11 CL
- What types of environmental factors contribute to the regulation of the number of wolves in the ecosystem? Explain the answer.
- Explain why not all the energy received from food is spent on the growth of the animal. Give at least three reasons.
- Brook trout lives in water with an oxygen concentration of at least 2 mg / l. When its content drops to 1.6 2 mg / l or less, the trout dies. Explain the reason for the death of the trout using knowledge of the reaction rate of the trait.
- What characterizes the geographic mode of speciation? List at least three items.
- How is the regulation of the number of insects, insectivorous and birds of prey in a mixed forest ecosystem, if the number of insects increases?
- Blood-sucking insects are common inhabitants of many biocenoses. Explain in what cases they occupy the position of consumers of II, III and even orders in food chains.
- Find errors in the given text. Indicate the numbers of the proposals in which they are made, correct them.
1. The criterion of a species is a set of features that distinguish a given species from another. 2. The basis of the physiological criterion is the totality of environmental factors in which the species exists. 3. The genetic criterion is characterized by a certain karyotype. 4. An ecological criterion is a certain area occupied by a species in nature. 5. Other species criteria include: morphological, biochemical, geographic, etc. 6. To establish species, it is enough to use any one criterion.
- In the biogeocenosis of the forest, trees were treated with pesticides to kill mosquitoes and midges. Specify at least four consequences of the impact of this event on the biogeocenosis of the forest.
- Find errors in the given text. Indicate the numbers of the proposals in which they are made, correct them.
1. Ch. Darwin determined the driving forces of the evolution of the organic world.
2. To them he attributed the diversity of species, the struggle for existence and natural
ny selection. 3. C. Darwin believed that the material for evolution is not
hereditary variation. 4. He also called it a modification of
variability. 5. Natural selection, according to Darwin, plays creative boredom
role. 6. He considered natural selection as the main driving force)
evolution.
- Antibiotic treatment of human diseases caused by microorganisms over time becomes ineffective. It is necessary to search for new drugs. Explain in evolutionary terms how antibiotic resistance develops.
- Rodents are the largest order of mammals in terms of the number of species in the latitude of distribution. What makes rodents thrive in nature? Give at least three reasons.
- Why can a decline in the population of a species cause its extinction. Give at least three reasons. Explain your answer
- Find errors in the given text. Indicate the numbers of the proposals in which they are made, correct them.
1. The share of visible rays accounts for most of the energy of solar radiation reaching the earth's surface. 2. Life on Earth is possible only because long-wave rays are delayed by the ozone screen. 3. In small doses, infrared rays prevent the occurrence of rickets in humans. 4. Infrared rays are an important source of internal energy. 5. The influence of three areas of solar radiation on organisms is referred to as biotic environmental factors of influence.
- Why is a broad-leaved forest considered a more sustainable ecosystem than a forb meadow? Provide at least three pieces of evidence.
- The rate of photosynthesis depends on factors such as light, carbon dioxide concentration, water, and temperature. Why are these factors limiting for the photosynthesis reaction?
- Explain why the reduction in the number of wolves due to hunting in the biocenoses of the tundra leads to a decrease in the stocks of moss reindeer - food for reindeer.
- The oxygen cycle takes place in nature. What role do living organisms play in this process?
- Carp were launched into an artificial reservoir. Explain how this can affect the number of insect larvae, carp and pike living in it.
- Why is a mixed forest ecosystem considered a more sustainable ecosystem than a spruce forest ecosystem?
- In a small reservoir formed after the flood of the river, the following organisms were found: ciliates-shoes, daphnia, white planarians, a large pond snail, cyclops, hydra. Explain. Can this body of water be considered an ecosystem? Provide at least three pieces of evidence.
- What environmental factors contribute to the regulation of the number of wolves in the ecosystem?
- How is a natural ecosystem different from an agroecosystem?
- What is the role of bacteria in the nutrient cycle?
- Squirrels, as a rule, live in a coniferous forest and feed mainly on spruce seeds. What biotic factors can lead to a reduction in the squirrel population.?
- Clover grows in the meadow, pollinated by bumblebees. What biotic factors can lead to a decline in the clover population?
- What changes in biotic factors can lead to an increase in the population of the naked slug that lives in the forest and feeds mainly on plants?
- Find errors in the given text. Indicate the numbers of the proposals in which they are made, correct them.
1. A population is a collection of freely interbreeding individuals of different species, inhabiting a common territory for a long time.2. The main group characteristics of the population are the number, density, age, sex and spatial structures. 3. The totality of all the genes of a population is called the gene pool. 4. Population is a structural unit of living nature. 5. Population size is always stable.
- Why are plants (producers) considered the initial link in the circulation of substances and the transformation of energy in an ecosystem?
- As a result of volcanic activity in the ocean, an island was formed. Describe the sequences of ecosystem formation on a newly formed piece of land. List at least three items.
- As a result of a forest fire, part of the spruce forest burned out. Explain how it will self-heal. List at least three steps.
- In some forest biocenoses, mass shooting of diurnal birds of prey was carried out to protect chicken birds. Explain how this event affected the number of chickens.
- The color of the white hare's coat changes throughout the year: the hare is white in winter and gray in summer. Explain what type of variability is observed in an animal and what determines the manifestation of this trait.
- What is the difference between land-air environment and water environment?
- Find errors in the given text. Indicate the numbers of the proposals in which they are made, correct them.
- Explain how acid rain damages plants. Give at least three reasons.
- What are the morphological, physiological and behavioral adaptations to environmental temperature in warm-blooded animals?
- What role do birds play in the biocenosis of the forest? Give at least three options.
- Using the picture, determine which form of selection it illustrates. Justify the answer. Will the size of the ears of hares change in the course of evolution under the action of this form of natural selection, and under what conditions of life will this selection manifest itself?
Number of individuals
Sign value
- Birds and mammals have achieved great success in the evolution of mastered? ground-air environment compared to other vertebrates. Explain what common features of their organization contributed to this. Give at least three signs.
- Find errors in the given text. Indicate the numbers of the proposals in which they are made, correct them.
1. A population is a collection of freely interbreeding individuals of the same species, inhabiting a common territory for a long time. 2. Different populations of the same species are relatively isolated from each other, and their individuals do not interbreed. 3. The gene pool in populations of the same species is the same. 4. The population is the elementary unit of evolution. 5. A group of frogs of the same species living in the deep for one summer is a population.
- What are the characteristics of plants that live in arid zones?
- The body shape of the callima butterfly resembles a leaf. How did this shape of the butterfly's body form?
Exercise 1.
Consider the proposed scheme. Write in the answer the missing term, indicated in the diagram with a question mark.
Explanation: Reproduction of organisms is sexual and asexual (without the participation of germ cells).
The correct answer is asexual.
Task 2.
Choose two correct answers from five and write down the numbers under which they are indicated.
The hybridological research method is used
1. Embryologists
2. Breeders
3. Genetics
4. Ecologists
5. Biochemists
Explanation: hybridological method - a method of obtaining hybrids. They are used in genetics to determine the characteristics and inheritance of a trait and in breeding to develop new breeds, varieties, strains.
The correct answer is 23.
Task 3.
An mRNA molecule takes part in protein synthesis, the fragment of which contains 96 nucleotide residues. Determine the number of nucleotide residues in the region of the DNA template chain that carry information about the primary structure of the protein.
Explanation: during transcription (copying a section of DNA - a gene - onto mRNA) on DNA and mRNA, the same number of nucleotides is obtained as a result, since the gene encodes a protein and the mRNA must transmit this encoded information unchanged.
In this task, non-coding regions of DNA are neglected - introns, which are excised from DNA, so that mRNA is smaller than DNA.
The correct answer is 96.
Task 4.
The signs listed below, except for two, are used to describe the structure and functions of the depicted cell organoid. Identify two signs that "fall out" from the general list, and write down in the table the numbers under which they are indicated.
1. Packs and carries synthesized substances out of the cell
2. Participates in the formation of lysosomes
3. Provides oxidative phosphorylation
4. Consists of a single membrane
5. Contains interconnected grains
Explanation: The figure shows the Golgi apparatus. It packs and takes synthesized substances out of the cell (for example, proteins from ribosomes enter the Golgi apparatus and then are distributed throughout the cell), participate in the formation of lysosomes, and are single-membrane. They do not carry out oxidative phosphorylation (like mitochondria) and do not contain gran (like chloroplasts).
The correct answer is 35.
Task 5.
Establish a correspondence between the characteristics and phases of photosynthesis.
Characteristics
A. Photolysis of water
B. Carbon dioxide fixation
B. Breakdown of ATP molecules
D. Excitation of chlorophyll by light quanta
D. Glucose synthesis
Phases of photosynthesis
1. Luminous
2. Dark
Explanation: Light is required for the light phase of photosynthesis. It includes: photolysis of water, splitting of ATP molecules, excitation of chlorophyll by light quanta. All processes take place on the membrane. The dark phase of photosynthesis does not require light. It includes the Calvin cycle, during which CO2 fixation and glucose synthesis occur.
Correct answer: 12112.
Task 6.
Determine the ratio of females and males in the offspring formed by crossing two heterozygotes. Write down the answer in the form of a sequence of numbers showing the ratio of phenotypes, in descending order.
Explanation: the question is posed incorrectly, since the offspring does not depend on the genotype. The ratio of females and males will always be 50:50 (i.e. 1:1).
The correct answer is 11.
Task 7.
The following characteristics, except for two, are used to describe the causes of combinative variability.
1. Chance meeting of gametes during fertilization
2. Spiralization of chromosomes
3. DNA replication in interphase
4. Gene recombination during crossing over
5. Independent segregation of chromosomes in meiosis
Explanation: combinative variability is determined by: random meeting of gametes during (different combinations) fertilization, gene recombination during crossing over, or independent chromosome segregation in meiosis. Chromosome spiralization and DNA replication in interphase are not characteristics of combinative variability.
The correct answer is 23.
Task 8.
Establish a correspondence between the characteristics and stages of formation of lancelet embryos.
Characteristics
A. Invagination of a group of cells into the blastula
B. Mitosis of the zygote
B. Formation of the walls of the primary intestine
D. Formation of the blastocoel
D. Formation of blastomeres
Stages of embryogenesis
1. Single layer embryo
2. Bilayer embryo
Explanation: blastula is a single-layer stage, which means that everything that enters it belongs to the single-layer period of embryo development (zygote mitosis, blastomere formation, blastocoel formation). During gastrulation, protrusion occurs and the protruding cells represent the second layer, that is, the characteristics of a two-layer embryo include: The protrusion of a group of cells inside the blastula and the formation of the walls of the primary intestine.
The correct answer is 21211.
Task 9.
1. Are perennials
2. Contain chloroplasts with chlorophyll
3. Have flowers and inflorescences
4. Form fruits with seeds
5. Represented by a variety of life forms
6. Propagated by seeds
Explanation: angiosperms - the most progressive group of plants. They differ from all others in the presence of a flower and a fruit. Also, unlike gymnosperms, they are represented by a variety of life forms: grasses, shrubs, trees (gymnosperms are only tree forms). Common features: perennial plants, the presence of chloroplasts with chlorophyll, reproduction by seeds.
The correct answer is 126.
Task 10.
Establish a correspondence between animals and the characteristics of body temperature.
Animals
A. house sparrow
B. quick lizard
B. common dolphin
G. Nile crocodile
D. common newt
E. Common mole
Features of body temperature
1. Constant
2. Fickle
Explanation: birds (house sparrow) and mammals (common dolphin, common mole) have a constant body temperature (they are warm-blooded). Amphibians (common newt) and reptiles (fast lizard, Nile crocodile) have unstable body temperature (they are cold-blooded).
Correct answer: 121221.
Task 11.
Establish the sequence of arrangement of systematic groups of plants, starting with the smallest taxon. Write down the corresponding sequence of numbers in the table.
1. Common radish
2. Angiosperms
3. Cruciferous
4. Dicotyledons
5. Radish
6. Eukaryotes
Explanation: arrange the systematic groups, starting with the smallest.
View Common radish
Rod Radish
Cruciferous family
Class Dicotyledonous
Department Angiosperms
Superkingdom of Eukaryotes
The correct answer is 153426.
Task 12.
Choose three correct answers out of six.
Leukocytes are blood cells that
1. Formed in the red bone marrow
2. Able to change their shape
3. Contain kernels
4. Synthesize hemoglobin
5. They secrete substances for the formation of a blood clot
6. Ripe in the nerve nodes
Explanation: leukocytes - white blood cells, they are responsible for immunity, can absorb foreign particles by changing the shape of the cell (phagocytosis), have nuclei, are formed in the red bone marrow. They do not synthesize hemoglobin, do not participate in the formation of a blood clot, do not mature in the nerve nodes.
The correct answer is 123.
Task 13.
Establish a correspondence between the characteristics and departments of the nervous system.
Characteristics
A. Coordinates the work of internal organs
B. Regulates metabolic processes
B. Acts autonomously, regardless of the desire of a person
G. Provides voluntary movements of the limbs
D. Regulates the activity of smooth muscles
E. Regulates skeletal muscle contraction
Departments of the nervous system
1. Vegetative
2. Somatic
Explanation: the somatic nervous system controls the work of the muscles. Autonomic (autonomous) nervous system - controls the work of internal organs, that is, the autonomic nervous system coordinates the work of internal organs, metabolic processes, and the activity of smooth muscles. The somatic nervous system regulates voluntary movements of the limbs, that is, the contraction of skeletal muscles.
The correct answer is 111212.
Task 14.
Establish the sequence of location of the structures of the eyeball, starting with the cornea. Write down the corresponding sequence of numbers in the table.
1. Retinal neurons
2. Vitreous body
3. The pupil in the pigment shell
4. Light-Sensitive Rods and Cones
5. Convex transparent part of the albuginea
Explanation: Consider the structure of the eyeball.
The most external structure is the convex transparent part of the membrane, then the pupil in the pigment membrane, then the vitreous body, then the neurons of the retina, and finally the light-sensitive cells - rods and cones.
The correct answer is 53214.
Task 15.
Choose from the text three sentences that describe the paths of macroevolution of the organic world. Write down the numbers under which they are indicated in the table.
Explanation: the ways of macroevolution of the organic world are described in sentences 1, 4 and 5.
Macroevolution is the process of formation of large systematic units. We pay attention to the phrases: "aromorphosis", "general degeneration", "increase in the level of organization", "morphophysiological regression".
The correct answer is 145.
Task 16.
Establish a correspondence between the characteristics and criteria of the species Honey bee.
Characteristics
A. Public lifestyle
B. Size difference between males and females
B. Development of larvae in combs
D. Presence of body hairs
D. Feeding on nectar and pollen of flowers
E. Compound eyes
View criteria
1. Morphological
2. Environmental
Explanation: morphological criterion describes the external structure of organisms, that is, the difference in the size of males and females, the presence of hairs on the body, compound eyes. The ecological criterion describes the interaction of a species with the environment and with other organisms: a social way of life, the development of larvae in combs.
The correct answer is 212121.
Task 17.
Choose three correct answers from six.
In the biogeocenosis, heterotrophs, unlike autotrophs,
1. Are producers
2. Provide a change of ecosystems
3. Increase the supply of molecular oxygen in the atmosphere
4. Extract organic matter from food
5. Turn organic residues into mineral compounds
6. Act as consumers or decomposers
Explanation: heterotrophs - living organisms that consume organic substances and turn them into mineral compounds. In the food chain, heterotrophs act as consumers or decomposers. Producers are autotrophs, green plants release oxygen during photosynthesis, increasing its supply in the atmosphere.
The correct answer is 456.
Task 18.
Establish a correspondence between the characteristics and types of ecosystems.
Characteristics
A. A variety of circuits and power networks
B. Great variety of species
B. Presence of monocultures
D. Closed circulation of substances
E. Instability over time
E. The need for additional energy
Ecosystem types
1. Agrobiocenosis
2. Biogeocenosis
Explanation: agrobiocenosis - an artificial community, is unstable, as it has a number of disadvantages: the presence of a monoculture, instability over time, the need for additional energy.
Biogeocenosis is a natural community that is quite stable, as there are a variety of food chains and networks, a wide variety of species, a closed cycle of substances.
The correct answer is 221211.
Task 19.
Establish the sequence of formation of aromorphoses in animals in the process of evolution. Write down the corresponding sequence of numbers in the table.
1. Appearance of internal fertilization
2. The emergence of the sexual process
3. Chord formation
4. Formation of five-fingered limbs
Explanation: among the listed signs, the earliest is the appearance of the sexual process (still in the Coelenterates), then internal fertilization, the appearance of the notochord and the formation of five-fingered limbs.
The correct answer is 2134.
Task 20.
Consider the picture depicting cell division and determine its phases, the set of chromosomes in daughter cells, and what specific cells are formed as a result of such division in plants.
Fill in the blank cells of the table using the terms given in the list. For each lettered cell, select the appropriate term from the list provided.
List of terms
1. Prophase, metaphase, telophase
2. Somatic
3. Diploid
4. Prophase 2, metaphase 2, anaphase 2, telophase 2
5. Prophase 1, metaphase 1, anaphase 1, telophase 1
6. Haploid
7. Dispute
8. First meiotic division
Explanation: The figure shows the second division of meiosis, as haploid cells are formed. In plants, spores are formed during meiosis, and gametes are formed during mitosis (in animals, the opposite is true).
Correct answer - A - cell division phases - prophase 2, metaphase 2, anaphase 2, telophase 2
B - a set of chromosomes in daughter cells - haploid
B - what specific cells are formed in plants - spores
The answer is 467.
Task 21.
Analyze the "Survival of the mouflon at the London Zoo" graph. Select statements that can be formulated based on the analysis of the data presented.
Statements:
1. A group of animals was studied, consisting of 79 individuals
2. 3-4 individuals approximately live up to 9.5 years
3. Born individuals often die in the third year of life
4. Most individuals live up to eight years
5. In the original population, the average age of individuals is one year
Explanation: as can be seen from the graph, the largest number of individuals are aged 1-4 years (12-48 months). A total of 79 individuals were studied, but only 3-4 of them live up to 9.5 years (114 months).
The correct answer is 12.
Task 22.
Several whiskers were taken from one strawberry plant, rooted and mature plants were obtained, which were transplanted to another part of the plantation. However, the fruits of some daughter plants were smaller than those of the parent plant. Name the method used to propagate strawberries. Explain the reason for the appearance of small fruits.
Explanation: the task shows the vegetative method of reproduction. The size of the fruit may vary within the normal range of reaction, depending on environmental conditions. This type of variability is called modification or phenotypic.
Task 23.
What plant organs are indicated in the figure by numbers - 1, 2, 3? What is their role in plant life? What organ are they a modification of?
Explanation: 1 - tuber, 2 - bulb, 2 - rhizome. These organs are modified shoots. With the help of modified shoots, the plant can reproduce vegetatively.
Task 24.
Find errors in the given text. Indicate the numbers of sentences in which errors were made, correct them.
1. The endocrine glands have ducts through which the secret enters the blood. 2. These glands secrete biologically active regulatory substances - hormones. 3. All hormones are chemically proteins. 4. Pancreatic hormone - insulin. 5. It regulates blood glucose. 6. With its deficiency, the concentration of glucose in the blood decreases.
Explanation: mistakes were made in sentences 1, 3, 6.
Proposal 1 - the endocrine glands secrete the hormone into the blood and do not have ducts, the external secretion glands secrete the secret into the duct.
Proposition 3 - not all hormones are proteins (for example, adrenaline is not a protein).
Proposition 6 - insulin helps glucose enter the cells, so when it is lacking, the concentration of glucose in the blood does not decrease, but increases (this disease is called diabetes mellitus).
Task 25.
Mammals are a thriving group of vertebrates. Explain what aromorphoses allowed them to achieve biological progress. List at least four features.
Explanation: mammalian aromorphoses:
1. Warm-bloodedness - independence from ambient temperature (high level of metabolism).
2. The appearance of wool - keeping warm.
3. Differentiation of teeth - they can eat different foods.
4. Four-chamber heart - complete separation of venous and arterial blood.
5. Strongly developed cerebral cortex (characteristically complex behavior).
6. Outer ear - sound collects and passes into the auditory tube.
7. The ability to feed babies with milk and care for offspring.
Task 26.
Why is a broadleaf forest considered a more sustainable ecosystem than a forb meadow? Give at least three pieces of evidence.
Explanation:
1. A forb meadow is represented by plants with only one life form - herbaceous plants, and in a broad-leaved forest there are grasses, shrubs, and trees (there is layering).
2. There are more branched chains in the broad-leaved forest.
3. Broad-leaved forest has more variety of species.
Task 27.
The chromosome set of wheat somatic cells is 28. Determine the chromosome set and the number of DNA molecules in the root tip cells in prophase at the end of the telophase of mitosis. Explain the results obtained in each phase.
Explanation: somatic cells contain a diploid set of chromosomes. In the cells of the root tip in prophase, the set of chromosomes and the number of DNA molecules are 2n4c - 56 molecules (since replication occurred), at the end of the telophase of mitosis - 2n2c - 28 molecules (sister single chromatid chromosomes are in the daughter cells).
Task 28.
Blood type and Rh factor are autosomal recessive traits.
The blood group is controlled by three alleles of one gene: I0, IA, IB. The IA and IB alleles are dominant over the I0 allele. The first group (0) is determined by the recessive I0 genes, the second group (A) is determined by the dominant allele IA, the third group (B) is determined by the dominant allele IB, and the fourth (AB) is determined by two dominant alleles - IAIB. Positive Rh factor (R) dominates over negative (r).
The mother has the second group and Rh positive (heterozygous for the Rh factor), the father has the third blood group and positive for Rh (homozygous for the Rh factor). My son has type I blood and is Rh positive. Make a scheme for solving the problem. Determine the genotypes of the parents and son. Determine what blood types and Rh factor children in this family can have, their possible genotypes and the ratio of phenotypes. What law of heredity is manifested in this case?
Explanation: mother's genotype - IAI0Rr
father's genotype - IBI0RR
son's genotype - I0I0R_
P: IAI0RR x IBI0RR
Gametes: IAR, I0r, IAr, I0R x IBR, I0R
We have the following splitting by 4 phenotypes and 8 genotypes.
F1: IAIBRR, IAIBRr - fourth blood type, Rh positive
IAI0RR, IAI0Rr - second blood type, Rh positive
IBI0Rr, IBI0RR - third blood type, Rh positive
I0I0Rr, I0I0RR - first blood type, Rh positive
The phenotype ratio is 1:1:1:1.
The law of independent inheritance appears.
Option 7. Biology. A set of materials for preparing students for the Unified State Examination 2018. G.S. Kalinova, L. G. Prilezhaeva.