Answer:
B. Toes and palms are anterior.
Explanation:
In an anatomical position, directional terms are used to describe the position of the body parts with respect to each other. Anterior, also referred to as ventral position, means the specific body part is at the front of the body or facing forward.
According to the given position of the standing body, palms are facing forward making them anterior in position. The body is standing on the floor with flat feet which means that the toes of the feet are also facing forward.
This makes both toes and palms of the given standing body to be anterior in their position.
In the anatomical position, the body is upright with eyes facing forward and arms at the sides, palms and feet facing forward. In this stance, it is accurate to say that the toes and palms are anterior (facing to the front of the body), not posterior (facing toward the back of the body).
Explanation:In the anatomical position, the body is positioned in the upright posture with the feet flat on the floor. The face and eyes facing forward and arms are positioned at the sides, with palms turned so they are facing forward as well. In this stance, it is most accurate to say that the toes and palms are anterior (B).
Anterior refers to the front of the body or positioned nearer to the head. Therefore, when standing in anatomical position, the palms and toes are indeed anterior, as they are oriented toward the front. The term posterior, on the other hand, refers to the back of the body or something further away from the head. So, in anatomical position, the palms and toes are not posterior.
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What is meant by variable expressivity in genetics?
A The product of one gene controls the expression of another gene.
B A certain percentage of individuals with a particular genotype fail to express the associated phenotype.
C A single genotype produces a range of phenotypes that differ in the degree or magnitude of expression of the particular trait specified by the gene.
D A single genotype produces multiple distinct phenotypes that affect different functions.
Answer:
C A single genotype produces a range of phenotypes that differ in the degree or magnitude of expression of the particular trait specified by the gene.
Explanation:
Variable expressivity refers to the range of signs and symptoms that can occur in different people with the same genetic condition.
For example, the features of Marfan syndrome vary widely— some people have only mild symptoms (such as being tall and thin with long, slender fingers), while others also experience life-threatening complications involving the heart and blood vessels. Although the features are highly variable, most people with this disorder have a mutation in the same gene (FBN1).
Solomon is studying for class. To remember the term _____, he uses the analogy of a thermostat in a house. For instance, when the temperature falls below the set point, the heat will turn on to correct the temperature.
Answer:
Homeostasis
Explanation:
Homeostasis refers to maintaining the constant internal body conditions and mostly use the feedback loops to counteract any deviations from the narrow physiological range of several variants such as body temperature, blood glucose levels, etc.
For example, the human body maintains the internal body temperature around 37 degrees Celsius irrespective of the temperature of the surroundings.
When the body temperature rises above the standard range, the secretion of sweat and its evaporation to create the cooling effect is one of the several mechanisms that serve to lower down the body temperature.
Likewise, when the body temperature falls below the normal physiological range, increased heat production and prevention of heat loss are triggered by hypothalamus via autonomic nerve system to increase the body temperature again.
A marine clam is mistakenly added to a freshwater aquarium. What will happen to the clam and why? Popcorn sold at movie theaters is very salty, causing people to become thirsty and to buy so drinks. Explain why salty popcorn causes this thirst.
Final answer:
A marine clam added to a freshwater aquarium would not survive due to osmosis causing its cells to swell and burst. Salty popcorn causes thirst because the salt draws water out of our cells through osmosis, leading to dehydration and the body's thirst response.
Explanation:
If a marine clam is mistakenly added to a freshwater aquarium, it will likely not survive. This is because marine clams are adapted to living in saltwater, which has a higher solute concentration than freshwater. When placed in freshwater, water will enter the clam's cells through osmosis, causing its cells to swell and potentially burst, leading to the clam's death.
Salty popcorn causes thirst because salt is a solute that increases the osmolarity of the body's fluids. When we consume salty popcorn, the high concentration of salt in the popcorn draws water out of our cells through osmosis, leading to a decrease in hydration levels. This triggers the body's thirst response, prompting us to drink more fluids to rehydrate.
iv u answer this ? youll get points
the answer is A. covalent bonds
You arrive to find a 25 year old male lying in bed pulseless
During _____, the genital areas become engorged with blood, a woman's vagina expands and secretes lubricant, and her breasts and nipples may enlarge
Answer:
excitement phase
Explanation:
Answer: during the was itchiness
Explanation:
In recent years, there has been controversy among biologists about whether Neanderthals should be placed within the same species as modern humans or into a separate species of their own. Most DNA sequence data analyzed at this point indicated that there was probably little or no gene flow between Neanderthals and Homo sapiens. Which species concept is most applicable in this example?
Answer:
The correct answer would be - biological species concept.
Explanation:
The biological species concept is a concept of speciation or how a species forms in nature. According to this, a species is the group of the population that can naturally or potentially interbreed with each other, not on the basis of their physical similarities or habitats.
The physical appearance could be useful as recognizing a species but not defining it. As neanderthals show very little or no gene flow with a modern human it means they do not belong to the same species as modern homo sapiens.
Thus, the correct answer is- biological species concept.
The biological species concept, focusing on reproductive isolation and interbreeding, appears relevant when considering the genetic relationship between Neanderthals and modern humans. However, evidence of gene flow suggests a more nuanced view, complicating a strict definition based on reproductive isolation.
Explanation:The question revolves around which species concept is most applicable when discussing the relationship between Neanderthals, Denisovans, and modern humans (Homo sapiens). The biological species concept, which defines species based on the ability to interbreed and produce fertile offspring, is relevant here. However, the evidence suggests that gene flow did occur among these groups, complicating the strict application of this definition.
DNA analysis indicates that modern humans have between 1 to 4 percent Neanderthal DNA, and some individuals also have Denisovan DNA. This gene flow is evidence of interbreeding among these Homo species. The presence of Neanderthal DNA in modern humans challenges the notion of Neanderthals being a completely separate species, suggesting that they may have been absorbed by the Homo sapiens population.
John is a veteran who suffered traumatic brain damage while in combat. Despite having all of his limbs and suffering no other health symptoms, he experiences phantom pain in his extremities. What could be going on with his brain?
Answer:
He could be suffering with brain damage in his frontal area, it has symptoms of migraine, fluids excreting from his nasal areas and dizziness.
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John's phantom pain in his extremities, despite no physical injury, is most likely caused by disruptions in his brain's interpretation of sensory signals as a result of his traumatic brain injury. The conflicting information from the sensory areas and motor areas in his brain can create a perception of pain, known as phantom limb pain.
Explanation:John's symptoms can be attributed to a phenomenon known as phantom limb pain, which is frequently experienced by individuals who have lost a limb or suffer from neurological damage. Despite the limb being physically present, John's traumatic brain injury may have caused disruptions in the way his brain interprets sensory signals, leading to the sensation of pain in a limb that is otherwise perfectly healthy. The sensory areas and the motor areas in the brain, in such cases, can sometimes send conflicting information, causing a perception of pain. For instance, the motor cortex in John's brain might still be sending out commands for the limb to move, but the absence of corresponding feedback from the sensory cortex could result in the experience of phantom pain.
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Given that CO₂ is produced by cellular respiration, why does the amount of CO₂ in the atmosphere remain relatively constant? (When answering this question, exclude the impact of human activities on atmospheric CO₂.)A) CO₂ is converted in photosynthesis to carbohydrates.B) CO₂ is split apart during photosynthesis.C) CO₂ mostly forms carbonate rocks.D) CO₂ is trapped in dead organisms' bodies.E) CO₂ is a buffer.
Answer:
A) CO₂ is converted in photosynthesis to carbohydrates.
Explanation:
Photosynthesis is the process wherein the phototrophs such as green plants fix the atmospheric carbon dioxide into organic nutrients (glucose). The oxygen gas is released as a by-product of the process.
During photosynthesis, the splitting of water is driven by solar energy and electron transport during light reactions produces ATP and NADPH. The ATP and NADPH drive the light-independent reactions of photosynthesis wherein the carbon dioxide gas is fixed into glucose.
For the purpose, the green plants absorb the carbon dioxide present in the air through stomata. The absorption of CO2 for photosynthesis keeps the atmospheric levels of the gas relatively constant.
A persons skin cells and eye make different types of proteins to perform their functions. What's is the source of the instructions from which all of the proteins are made
Answer: From DNA
Explanation: DNA is the inheritance molecule in humans and carries the information for every protein needed for our metabolism. DNA is transcripted to produce RNA and this is translated to produce proteins. Each type of cells has the same DNA (With some variations due to mutations in life) but their DNA express differently according to their specialized function.
Virgin queens will only exit the hive for her mating flight(s) if the following condition is met: _________
Answer:
The correct answer is "the temperature is above 23 °C but not exceeding 40 °C".
Explanation:
The main function of virgin queens in a bee's hive is reproduction. Normally virgin queens do not exit the hive except to perform mating flight(s), which normally are done with 10–20 drone bees and then return to the hive as mated queen bees. Usually virgin queens perform her mating flight(s) in ideal temperature conditions, which are with a temperature above 23 °C but not exceeding 40 °C.
Answer: The temperature is above 23 degrees C (73 degrees F)
Explanation: Under normal circumstances, there will only be one queen in a hive and she will normally remain in the hive. She will only leave to do her mating dance with the drone bees. The only purpose of the drone bees is to mate with the queen. She will usually fly at about ten metres above the ground towards an area where drones from the surrounding area congregate. The drones will start to pursue the queen at which point she will fly at an increasing altitude with the drones chasing her. Eventually she will be mated on the wing by several drones. After this she will return to the hive and will start laying eggs a couple of days later.
Though many are apt to believe that the bones from a recent discovery are those of a direct ancestor of modern humans, some scientists are skeptical, and contend that the remains, while suggesting a common ancestor, are but a vestige of one of evolution's many______ experiments.A. nobleB. unviableC. intuitiveD. unsuccessfulE. archaicF. ingenious
Answer:
Answered
Explanation:
Though many are apt to believe that the bones from a recent discovery are those of a direct ancestor of modern humans, some scientists are skeptical, and contend that the remains, while suggesting a common ancestor, are but a vestige of one of evolution's many_ unsuccessful._____ experiments.
On looking at the keyword vestige which means remains. If something is in remains of something and it is evolution, then that thing must have been unsuccessful. Rest all options look absurd with context of the question.
Waters high heat capacity protects organisms in the ocean from what?
Answer:
Heat fluctuations
Explanation:
Water's high heat capacity means that it requires a lot of energy to raise the temperature of a unit volume of water by one degree. It also requires to lose this same amount of energy to lower its temperatures by one degree.
This means that as land temperatures fluctuate a lot from day to night depending on the rate of sunlight hitting the earth, the waters of the oceans remain more or less within very a small range of temperatures. This protects the organism of the oceans from high heat fluctuations that may cause heat shock.
Which of the following classes of macromolecules always contains a carbohydrate portion? View Available Hint(s) Which of the following classes of macromolecules always contains a carbohydrate portion? Nucleic acids Water Proteins Lipids Submit
Answer:
Nucleic acids
Explanation:
Remember these long strands could be the ADN or the RNA, in both cases, they are formed by nucleotids, that means a complex of three parts.
A nucleotid is conformed by:
a) a nitrogenous base that in the case of DNA could be Adenine (A), Guanine (G) , citocine (C) o thymine (T). In the case of ARN are almost the same, the difference is instead of having Thymine, it will have uracile (U).
b) a phosphate group
c) a carbohydrate, in the case of ADN it will be Dexosyrribose and in the case of ARN will be ribose sugar.
While developing countries may suffer from famine and starvation, the US and other developed countries create _____________that promote eating energy-dense foods and discourage regular physical activity.a) orexigenic environments
b) obesogenic environments
c) anorexigenic environments
d) lipogenic environments
Answer:
The correct answer is option b) "obesogenic environments".
Explanation:
According to the article of Lake A "Obesogenic environments: exploring the built and food environments" (2006), an obesogenic environment is defined as "'the sum of influences that the surroundings, opportunities, or conditions of life have on promoting obesity in individuals or populations". This kind of environment is presented in the US and other developed countries, which contrast with the environment in developing countries who may suffer from famine and starvation.
An abundant and continual supply of ATP is necessary for all living cells. Active muscle cells require an extraordinary amount of ATP to permit strenuous exercise for prolonged periods. Toxins, reduced blood flow, and a compromised respiratory system can interfere with the transport of oxygen to active cells. A runner in a marathon faces multiple obstacles to continue to produce sufficient ATP to remain competitive.When oxygen delivery becomes insufficient to support a runner's aerobic metabolism, cells switch to an emergency mode in which __________.
Answer:
Explained.
Explanation:
When oxygen delivery becomes insufficient to support a runner's aerobic metabolism, cells switch to an emergency mode in which ATP is insufficiently produced and is lactic acid is produced as by product. Thus the runner finds difficult to remain competitive in the race because of lack energy.
To overcome this state the runner needs to increase his/her oxygen in take. This why it is advised to breath deeply.
Final answer:
In the absence of sufficient oxygen, muscle cells switch from aerobic to anaerobic respiration to produce ATP, but this also leads to the production of lactic acid, causing muscle fatigue.
Explanation:
When oxygen delivery becomes insufficient during strenuous activity like marathon running, muscle cells switch to an emergency mode called anaerobic respiration. During everyday activities and light exercise, the mitochondria in muscle fibers produce ATP through a process called aerobic respiration, which requires oxygen to break down glucose and generate a large amount of ATP efficiently. However, during intense exercise, when oxygen becomes limited, cells rely on anaerobic respiration to produce a small amount of ATP, which unfortunately leads to the production of lactic acid. As a consequence, this can lead to muscle fatigue and discomfort, making it challenging to sustain prolonged physical activity.
A regional lobster management board recently proposed a five-year moratorium on lobster fishing in the Atlantic waters south of Cape Cod based on a study of the lobster population. Which of the following statements is not correct
a. lobsters are rival but not excludable
b. the lobster population is an example of the tragedy of the commons
c. reducing the quota on the number of lobsters any fisher can catch would have a protective effect on the lobster population
d. if left unregulated, the lobster population will likely increase.
Answer:
Statement D is not correct.
Explanation:
a. Lobsters are rival but not excludable: This is correct, as lobster is a common resource to which everybody can get access to with no need to pay for it. Besides, a person can consume only one animal.
b. The lobster population is an example of the tragedy of the commons: This is correct, since people, acting by their own needs or interests, may exceed the capture of too many lobsters, affecting their population and, therefore, other users.
c. Reducing the quota on the number of lobsters any fisher can catch would have a protective effect on the lobster population: This is correct, since reducing the number of lobster catches will allow the animal population to reproduce more, leaving offspring capable of reaching sexual maturity, mating and reproducing again, and thus increasing the population size and stabilizing it.
d. If left unregulated, the lobster population will likely increase: This is not correct. There need to be some regulation or management, because if not these animals will continue to be caught, even in the reproductive season, not allowing the population to stabilize. In this case, the population will likely decrease, rather than increase.
A rain forest has a high level of biodiversity because it has
it has so much because it has a lot of animals with a lot of plants its habitats are very unique.
Acclimatization (or physiological adaptation)a. occurs at the individual level during childhood. b. occurs at the individual level throughout an individual’s lifetime. c. occurs at the population level via natural selection. d. involves adaptations specifically to climate change.
Answer:
b. occurs at the individual level throughout an individual’s lifetime
Explanation:
Adaptation differs from evolution in the sense that, adaptation can occur at different levels and all the time. For example if you take a dog to colder climate it will grow thick fur or if you take it to a hot climate it will lose a little bit of it. Changes during childhood are just part of the development of the body. Changes that occur at a population level via natural selection is evolution is different because adaptation can happen at the organism level but evolution needs be at the population level. If climate change affects an specific habitat animals can adapt to it, but if they develop different traits due to this climate change that would be evolution.
Acclimatization, or physiological adaptation, occurs at the individual level throughout an individual's lifetime and enables an organism to adjust to changes in its environment. It does not involve adaptations specifically to climate change.
Explanation:Acclimatization, or physiological adaptation, occurs at the individual level throughout an individual's lifetime. It refers to the ability of an organism to adjust to changes in its environment, such as changes in temperature, humidity, altitude, or other factors. This process allows the organism to maintain optimal physiological functioning in different conditions.
For example, when a person moves to a high-altitude location, their body will undergo acclimatization to deal with the lower oxygen levels in the air. This may involve increasing the production of red blood cells and adjusting the breathing rate. Over time, the person's body will adapt to the altitude and function more efficiently in those conditions.
However, acclimatization does not involve adaptations specifically to climate change. It is a natural and ongoing process that occurs at the individual level, allowing organisms to survive and thrive in their changing environment.
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QUESTION 5
The weak acid in the following list is _____.
A)hydrochloric acid
B)sulfuric acid
C)nitric acid
D)acetic acid
The weak acid D) acetic acid.
Explanation:Acid are the substance which has pH below 7 and releases [tex]\bold{H^+}[/tex] ions when they are treated with aqueous solution. Based upon the rate of dissociation, the acids are classified as strong acids which has high dissociation rate and weak acid with low dissociation rate.
Acetic acid is a organic acid with the formula [tex]\text{CH_3COOH}[/tex]. It is a colorless acid and also named as ethonoic acid.
Among the given list of acid in the option which includes, Sulfuric acid, Nitric acid, Hydrochloric acid, and Acetic acid, first three are strong acids, whereas the lastly mentioned is a weaker one.
Answer:
D)acetic acid
Explanation:
ap3x
Cholesterol is a ________, which ________. steroid; is a component of eukaryotic membranes steroid; is the basis for many animal and plant hormones terpene; is the basis for many animal and plant vitamins steroid; is a component of eukaryotic membranes and is the basis for many animal and plant hormones fatty acid; functions in energy storage
Answer:
Steroid; is a component of eukaryotic membranes.
Explanation:
Cholesterol is one of the most important chemical synthesized by all the animals. The chemical formula of cholesterol is C27H46O. The cholesterol in solid state was first given by C27H46O.
Cholesterol is present in the plasma membrane and maintain its membrane fluidity. Cholesterol is an important structure of the plasma membrane and acts as a pre cursor for various hormone. The cholesterol is a type of sterol and a lipid.
Thus, the correct answer is option (1).
Ribozymes
a. are enzymes that degrade RNA and therefore have potential for clinical applications.
b. are self-catalytic RNA AND suggest that nucleic acids evolved before proteins.
c. are self-catalytic RNA. are complexes of ribosomes and RNA.
d. suggest that nucleic acids evolved before proteins.
A homozygous tomato plant with red fruit and yellow flowers was crossed with a homozygous tomato plant with golden fruit and white flowers. The F1 all had red fruit and yellow flowers. The F1 were testcrossed by crossing them to homozygous recessive individuals and the following offspring were obtained:Red fruit and yellow flowers—41Red fruit and white flowers—7Golden fruit and yellow flowers—8Golden fruit and white flowers—44
How many map units separate these genes?
Answer:
15 m.u.
Explanation:
The genes for fruit and flower color are located in the same chromosome and we have to determine the distance between them.
The initial cross between two homozygous individuals with different traits resulted in an homogeneous F1 with red fruit and yellow flowers. Because of Mendel's Law of Uniformity, we know that the red fruits and yellow flowers are the dominant alelles.
I will call:
R_ = red fruit
rr = golden fruit
Y_ = yellow flowers
yy = white flowers
Initial cross:P RY/RY x ry/ryF1 RY/ry
All F1 tomato plants have red fruit and yellow flowers because they have the R and Y alelle.
Test cross:RY/ry x ry/ryThe gametes produced by the homozygous individual can only be ry.
The gametes produced by the heterozygous individual can be:
RY - Parental
ry - Parental
Ry - Crossover
rY - Crossover
F2 progeny:
41 RY/ry (Parental, Red fruit and yellow flowers)
44 ry/ry (Parental, Golden fruit and white flowers)
7 Ry/ry (CO, Red fruit and white flowers)
8 rY/ry (CO, Golden fruit and yellow flowers)
Total= 100.
The formula to calculate genetic distance is:
Genetic Distance (m.u.)= Recombination Frequency X 100.
The recombination frequency is calculated as the number of crossover individuals divided by the total number of individuals.
Replacing the results in the formula, we have=
Distance = (7 + 8)/100 x 100
Distance = 15 map units.
The two genes - for fruit color and flower color in the tomato plant - are 15 map units apart. This is calculated based on the recombination frequency of the observed traits in the offspring.
Explanation:To determine the distance between genes, or the number of map units, we can use Morgan's law, which states that 1% recombinance equals 1 map unit (also termed a centimorgan). A recombinant is defined as an offspring whose combination of traits does not match either parent in the cross and is the result of cross-over events (recombination) during meiosis.
To find the recombination frequency, we total the number of recombinant offspring and divide it by the total number of offspring. In this case, we have 7 red fruit and white flowers and 8 golden fruit and yellow flowers which are recombinants, that makes 15 recombinant offspring. We have a total of 100 offspring. Therefore, the recombination frequency is 15/100 = 0.15, or 15%.
Therefore, these two genes (for fruit color and flower color) are 15 map units apart based on the recombination frequency.
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The development of simple stone tools by early hominids led to the ability to procure meat more efficiently. This in turn led to the change in diet that included larger amounts of protein. Many scholars believe that this shift in diet was a significant part of how our ancient ancestors adapted so quickly to a varied set of environments, and thus were able to begin cultural development. This demonstrates the intimate connection between:
a. evolution and technology b. nature and nurture
c. culture and environment d. biology and psychology
Answer:
nature and nurture
Explanation:
According to my research on studies conducted by anthropologists, I can say that based on the information provided within the question this demonstrates the intimate connection between nature and nurture. This can be said because in the question it illustrates how the advanced ability to hunt animals (nature) was a main aspect of our change in diet and ability to adapt rapidly (nurture).
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In artificial selection, humans provide the selective pressure for species to change and shape the evolution of various breeds. What provides the selective pressure in natural selection?
a) the environment
b) the degree of natural genetic variation in a population
c) disease
d)scientifically trained humans
Answer: a) The environment.
Explanation: Natural selection is one of the forces of evolution. Natural selection occurs when individuals in a population have a different reproductive success in certain environment. For example, imagine a mosquitoes population in a insecticide-free envrionment, the non-resistent mosquitoes will be more succesfull that the resistant ones. But when there's insecticide in the environment, the resistent mosquitoes will be more successfull that the non-resistent ones, because they die.
In bacteria, single polycistronic mRNA encodes for:
a. a single enzyme although there are many in the metabolic pathway.
b. multiple enzymes of the particular pathway.
c. a single mRNA which is split into multiple mRNAs before translation.
d. a single peptide with multiple catabolic sites.
e. none of the above.
Answer:
The correct answer is option b. "multiple enzymes of the particular pathway".
Explanation:
A polycistronic mRNA is defined as a single mRNA molecule that encodes for multiple proteins. Bacteria has developed the capacity of synthesizing polycistronic mRNAs from operon genes in order to encode for multiple enzymes of a particular biological pathway at the same time. This adaptation helps the bacteria to quickly start the biological pathway needed at the moment, which is particular useful when it faces stressful conditions.
WILL MARK BRAINLIEST MAX POINTS! Suppose a tropical storm hit your local coastal areas. Residents noticed a large amount of dead fish washed up on the beach following the storm. What physical factors of the aquatic ecosystem may have caused the fish die off?
Answer:
Maby cause it was a storm oil could ave leked nd killed the fish
During certain types of storms, the temperature can drop, killing and freezing the fish. This is the reason the dead fish were found by residents on the coast during the storm.
A high fever causes an enzyme to lose its three dimensional structure and function. Which bonds are broken when a protein denatures? A high fever causes an enzyme to lose its three dimensional structure and function. Which bonds are broken when a protein denatures? Hydrogen bonds non-polar covalent bonds ionic bonds polar covalent bonds
How is the sun used to make energy, and who uses it? How is that energy transferred to living organisms at different levels of the food web/food chain/energy pyramid?
Answer: Plants use the sun for photosynthesis to create food for themselves and animals eat plants and in return other animals eat the animal that eat the planets but each time an organism the next receives less energy : plant - 100% - small animal - 80% - large animal - 60%
Explanation:
Mammals first appeared during the ______. a. Cenozoic Era c. Mesozoic Era b. Paleozoic Era d. Cretaceous Period Please select the best answer from the choices provided A B C D
Answer:
C.
Explanation:
Mammals first appeared during the Mesozoic Era. The correct option among all the options that are given in the question is option "c". The Mesozoic Era is considered to have lasted for about 180 million years. The Mesozoic Era is divided into three parts and they are the Triassic, the Jurassic and the Cretaceous. The mammals are considered to have evolved during the Triassic period.