Biology Simulator Exam Area of ​​Engineering and Sciences Physics Mathematics IPN 2024 Higher Level

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Magnification is a measure of how large a microscope (or the set of lenses in a microscope) can make an object appear. So, if something is 1 mm wide in real life, in the microscope image it would be 400 mm wide.
The resolution of a microscope or lens is the shortest distance at which two points can be separated and distinguished as separate objects. The lower this value, the greater the resolving power of the microscope and the better the sharpness and detail of the image. If two bacterial cells were very close together on a slide, they might look like a single blurry spot on a low-resolution microscope, but would look like separate entities on a high-resolution one.
Lenses, there are two types: the eyepiece, at the top of the microscope, closest to the observer's eye, and the objective, close to the preparation. The eyepiece typically has a magnification of 10x (the "x" indicates "magnification") so it magnifies an image 10 times its normal size.

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DNA is a universal molecule that has the same composition and function in all living organisms, which is to store genetic information, unlike the cell wall, since both cells can present it, but the composition is different. The nucleoid only occurs in prokaryotic cells and the nuclear membrane only occurs in eukaryotic cells.

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An organelle or organelle is a subcellular structure that carries out one or more specific jobs in the cell, just as an organ does in the body. Among the most important cellular organelles are the nuclei, which store genetic information; mitochondria, which produce chemical energy, and ribosomes, which assemble proteins.

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Cell membranes are selectively permeable, regulating what substances can pass through and the amount of each substance that can enter or leave at any given time. Selective permeability is essential for the cell to obtain nutrients, eliminate waste, and maintain a stable internal environment different from its surroundings (maintain homeostasis).
The simplest forms of transport across a membrane are passive, since they do not require any energy expenditure by the cell. They consist of the diffusion of a substance through a membrane in favor of its concentration gradient, which is a region of space through which the concentration of substances changes. These will move naturally along their gradients in an area of ​​higher concentration. to another of lower concentration.

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The cell is the smallest portion of matter that can have its own existence. A living being can be made up of a single cell or millions of them. The cells of the human body have different shapes and sizes, according to the function they fulfill, and carry out all the processes necessary for their existence. It is independent of other similar units; but as the number of cells in the organism increases, interdependence is established. There is diversification of structure and function of these units.

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According to Mendel's first law, the F1 that is generated from pure breeds (BBxbb) all its offspring will have a heterozygous genotype (Bb). If these are crossed with each other to obtain the F2, their offspring according to Mendel's second Law will be in the proportion 3:1, therefore, the genotype of the parents is Bb for both.

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Biomolecules: The number of chemical elements that exist in nature is greater than one hundred.
However, not everyone participates in the composition of living matter; In fact, only six of them make up almost all of it and these are not the six most abundant on the planet. These are carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur. They have been called macroelements of living matter because they are found in large proportions in cells. Others, which are found in smaller proportions, have been called microelements. Examples of them are sodium, potassium, calcium, magnesium.

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The essential chemical elements are the primary bioelements: carbon, hydrogen, oxygen, nitrogen, phosphorus and sulfur. These atoms combine within our body to give rise to molecules that form living matter: biomolecules (sugars, fats, proteins and nucleic acids). Secondary bioelements: Ca, Na, K, Cl, I, Mg, Zn.

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The evidence of evolution revealed by molecular biology is even more concise. The degree of similarity reflects the proximity of the common ancestor, which allows us to reconstruct the phylogeny of these organisms. The chemical bases of DNA that interact with each other are like a stepladder where the handrails are the two strands wound around each other. The junction between the base pairs corresponds to the rung of the ladder. Each strand is formed by the alternation of a sugar (deoxyribose) and a phosphate group. In each sugar, one of the four nitrogenous bases is anchored: adenine (A), cytosine (C), guanine (G) or thymine (T). The two strands are held together by hydrogen bonds between complementary bases, that is, adenine with thymine, and cytosine with guanine.

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Genotype: The class of which one is a member based on the state of an organism's internal hereditary factors, its genes and by extension its genome. It is the genetic content of an organism.

Phenotype: The class of which one is a member based on the physical qualities observable in an organism including its morphology, physiology and behavior at all levels of description. The observable properties of an organism.

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During transcription (which takes place in the cell nucleus), mRNA molecules are formed from the genetic information in a cell's DNA. Once the mRNA is formed, it leaves the nucleus to the cytoplasm and reaches the ribosomes, where the amino acids are assembled to form a protein, according to the genetic code contained in an mRNA molecule.

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Penis: It is the copulatory organ and, therefore, responsible for leading the sperm to the outside.
Vagina: It is the part of the female body that connects the womb (uterus) and cervix to the outside of the body.
Scrotum: Its function is to keep the testicles at a temperature slightly lower than that of the body, since the germ cells are very sensitive to changes in temperature and slight increases produce sterility.
The efferent ducts or cones that emerge from Haller's network empty into the epididymal duct, also very folded, and constitute with the first portion of the latter the head of the epididymis, located at the upper pole of the testicle.
Ovaries: they are the organs that produce eggs or female sex cells and are also endocrine glands that produce estrogen and progesterone, the female sex hormones. They have a hard consistency and are almond-shaped, with a larger diameter of about 3,5 cm and 1,5 cm thick. Its surface is smooth before puberty, but after the maturation of the eggs and their cyclical release from the ovary (ovulation), it presents an irregular surface. In menopause, with the cessation of ovulations, it tends to become smooth again.
Epididymis: Its main functions are the transport, storage and maturation of sperm.
Fallopian tubes: Tubas or oviducts are the tubes that carry the eggs from the ovary to the uterus. They measure 10 or 12 cm and consist of four portions: pavilion, ampulla, isthmus and intramural portion. The sperm deposited in the vagina after intercourse travel through the uterus and enter the tubes through the uterine orifice, reaching the ampullary portion, where fertilization normally occurs. The movement of sperm is carried out by their own motility, helped by the movements of the tube. Only one sperm is involved in fertilization: as its head penetrates the egg, it becomes impermeable to the entry of other sperm.

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http://www.um.es/anatvet/Documentos/muestra_matronas.pdf
https://medlineplus.gov/spanish/ency/article/002342.htm

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Follicle-stimulating hormone stimulates the development of several follicles within each ovary.
Small follicle cells surrounding the oocyte secrete a small amount of estrogen.
The maturing follicle secretes large and increasing amounts of estrogen.
The increase in luteinizing hormone causes ovulation.
The corpus luteum secretes both estrogen and progesterone which further stimulate the growth of the endometrium.
If the egg is not fertilized, the corpus luteum begins to disintegrate around twelve days after ovulation.
Without the corpus luteum, estrogen and progesterone levels drop to a minimum and most of the endometrium of the uterus disintegrates.

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1. The uterine horns or Fallopian tubes are conduits for receiving and transporting unfertilized and fertilized eggs.

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Sexual reproduction of eukaryotic organisms occurs when offspring are produced by the fusion of the gametes (sperm and eggs) of two adults.

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DNA (deoxyribonucleic acid) is a relatively stable molecule with structural characteristics that maximize information storage and facilitate replication.

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Both prey and predators developed colors, patterns and shapes that resemble their environments. This mechanism is called camouflage and makes plants and animals inconspicuous, even when they are in plain sight.
Mimicry refers to a situation in which members of one species evolved to look like another species. By sharing a similar warning color pattern, many venomous species may benefit. Mimicry and camouflage should not be confused. If the animal disguises itself as another, it is mimicry; If it acquires the colors of the background, it is camouflage.

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Through photosynthesis, organisms with chlorophyll take CO2 from the atmosphere or dissolved in water to form more complex molecules such as carbohydrates, lipids, proteins and nucleic acids.
The general formula for photosynthesis is as follows:
6CO2 + 6H2O + Light = C6H12O6 (glucose) + 6O2
Carbon dioxide (CO2) is fixed in the connective tissue of the chloroplast. The fixed carbon dioxide is then used in the cytoplasm to synthesize sucrose.

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Alexander I. Oparin and John BS Haldane published (1924 and 1929, respectively) works on the origin of life with a materialist approach, conceiving the idea that a primitive atmosphere of a reducing chemical nature formed by methane, ammonia, water vapor and hydrogen , and that thanks to the action of ultraviolet rays and other forms of energy, these substances gave rise to various organic compounds such as amino acids. The theory is called chemosynthetics.

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The theory of evolution by natural selection, also called Darwinism, is based, among others, on the following principles:
Competition: Organisms fight for a limited resource, the large number of individuals leads them to compete and thus populations remain constant due to the death of sick, old, unable to reproduce, or poorly adapted organisms.
Variability: There are small differences between the characteristics of individuals; The more differences there are between individuals, the greater the variability.
Natural selection: Nature makes a selection of individuals with advantageous characteristics, this means that in the event of a change in the environment, organisms with that different characteristic will be able to survive because they are stronger, better nourished and more likely to reach survival. maturity.
Evolution: The fittest organisms live to reproduce and inherit advantageous characteristics to their offspring, and the longer they live, the older their offspring are and the greater the probability that their offspring will survive to continue inheriting the characteristics.
In the illustration you can see ancestral short-necked giraffes and two fates of the different varieties, where the one that has the survival advantage inherits that advantage to its descendants, while the one that does not have the advantage dies without the opportunity to leave offspring. so the next generation of giraffes does not possess the disadvantageous characteristics of the dead giraffe. It is clearly an example of Darwinism.

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The theory of spontaneous generation (abiogenesis) raises the idea that non-living matter can give rise to life on its own. It was thought that this matter contained an active principle and that with the help of certain suitable conditions a living being could be produced.

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Svante Arrenius, at the beginning of the 20th century, proposed that life had arrived on Earth in the form of bacteria from the outer space of a planet where they already existed; However, he had two objections: he does not explain how life originated on the planet where the bacteria came from and it would be impossible for any life form to cross the earth's atmosphere without burning up.

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Commensalism: type of relationship in which an organism called a commensal benefits from its relationship with another organism that neither benefits nor harms.

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Decomposers, also called saprophytes or detrivores, are organisms that feed on dead tissues or cells called detritus. They fulfill an important function in the ecosystem.

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An endemic species (also called microareal species) is that species or taxon (it can be a genus, for example) that is restricted to a very specific geographical location and outside of this location it is not found elsewhere.
The geographical extension can be very variable, with species endemic to a given population or to a province, country, (e.g. plants endemic to Australia, or plants endemic to Ibiza, animals endemic to the Amazon, there are also amphibians endemic to the Balearic Islands, insects and birds – for example.). As we see, endemic species can belong to any kingdom.

Bibliography.

Audesirk, Teresa; Audesirk, Gerald; Byers, Bruce E. 2008, Biology: life on earth8th ed, 928p.

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Biotic factors are all those that have life and cannot be isolated from the environment.
Due to their trophic level, they are classified as producers (autotrophic organisms), primary consumers (herbivores), secondary consumers, tertiary consumers (carnivores) and disintegrators and together, they form trophic relationships.
From Erice, Elena and Arturo González (2009) Biology The science of life. Mexico City Editorial Mc Graw Hill.

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Specifically, one of the characteristics of a terrestrial ecosystem is that matter and energy must function in cycles. When matter is not transformed to restart its cycle, balance is lost, therefore, the accumulation of waste is an alteration to the terrestrial ecosystem and can be considered not to be part of it, but rather an alteration of it.

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The carbon and water cycles are closely related to aerobic respiration and photosynthesis, since from their general formulas we can realize that carbon dioxide is the inorganic form of carbon used by plants in the process of photosynthesis to produce sugars, thus fixing the energy from sunlight. On the other hand, carbon dioxide, a product of aerobic respiration, is the residue that remains after extracting energy from carbohydrates produced in photosynthesis. While for photosynthesis to occur, water is necessary, which is decomposed into oxygen and hydrogen, the oxygen is integrated into the atmosphere and the hydrogen into the glucose molecule, where they remain until respiration, the oxygen is used to break down the pyruvate molecules into carbon dioxide and reintegrate the water molecule.
From Erice, Elena and Arturo González (2009) Biology The science of life. Mexico City Editorial Mc
Graw Hill.

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The Mexican gray wolf, at the beginning of the 70th century, inhabited the mountain areas of the northern and central states of Mexico. Due to campaigns for its eradication by the United States and Mexico, it was almost exterminated in the 2011s. In October 2010, CONANP released the first group of Mexican wolves in Sonora in one of the ecosystems they inhabited, but two Months later, the poisoning of some of its specimens was confirmed. SEMARNAT-XNUMX identifies it in the category of probably extinct in the wild.

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Among the abiotic factors are physical and chemical factors such as temperature, light, precipitation, wind, or soil composition:
Each factor is relevant in the ecosystem, adding a limitation to its optimal distribution and therefore, creating a mosaic of different biomes.
Temperature: Determines the activity and presence of organisms, the amount of water available and the speed of metabolic reactions. Soil composition: Here are the nutrients available to plants.
The annual amount of precipitation: Establishes the water available in the ecosystem and the available water influences the biomass generated by the products.
Wind: Causes hurricanes and tornadoes, disperses seeds, pollen and influences erosion.
Light: Its quantity determines photosynthesis and therefore, the increase in biomass in producers: the less light the less photosynthesis and the less biomass produced annually.

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Carl Von Linnaeus established the binomial nomenclature which indicates that the genus is written with the first letter capitalized and the subgenus the entire word in lowercase and both in italics.

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The ecosystem is the way in which living organisms and non-living elements of the environment interact as a unit. While biotic factors study living beings, abiotic or physical factors in ecology focus on the study of the non-living components of the environment that surround species and that allow them to live. By determining the availability of essential resources such as sunlight, water, oxygen, inorganic matter or minerals, it is clarified which organisms can survive in a place.

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Parasitism is a type of biological association between organisms of different species in which one of them (the parasite) benefits from this relationship and lives at the expense of the other (host), generally causing harm. Through this type of relationship, the parasite expands its survival capacity by using other species to cover its basic and vital needs, which do not necessarily have to be nutritional issues.
An endoparasite is a parasite that lives inside its host. There are many diseases that are caused by endoparasites, including malaria and leishmaniasis.
Some endoparasites (have a complex life cycle and require several types of hosts. They affect plants (endophytes) or animals (endozoans), they are classified as intracellular: those that live part of their life cycle inside the cell, and extracellular: they parasitize. outside the cell

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Coal led the first Industrial Revolution and was replaced by oil and gas in the second, leaving the emergence of new energy sources for later.
From the beginning of the Industrial Revolution until now, societies have greatly changed the way they consume energy. In the 18th century, fossil fuels did not exist, although oil had long been used for medical and military purposes, with wood being the main energy source. Today, renewables coexist alongside nuclear and the main fossil fuels, while electricity has been an essential part of development, facilitating storage and transportation.

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The flow of energy through ecosystems is the most important factor in their organization. Of the solar energy that reaches the Earth's surface, a very small fraction is derived to living systems. Even when the light falls in the area where vegetation is abundant such as in a jungle, cornfield, or marsh, only approximately 1 to 3% of health (calculated on an annual basis) is used in photosynthesis. Even so, a fraction as small as this can result in the production - from carbon dioxide, water and a few other minerals - of several thousand grams (by dry weight) of organic matter per year in a single square meter. field or forest, a total of approximately 120.000.000.000 organic matter per year worldwide.

The planet receives light and heat from the main source of its energy. Light is captured by photosynthetic organisms (generally algae and plants) and chemically converted (with other elements of nature) into heat and nutrients, these are incorporated into the food chain where they share the energy with each part of the link until it is exhausted. in the last participant.
In all cases, the individuals that form the chain die and rejoin the substrate to restart the photosynthesis process.
In the case of energy (sunlight) that is not captured by the photosynthetic process, it will be reflected to the outside of the planet and the heat absorbed by the soil.