Answer:
Perimysium.
Explanation:
Perimysium: It is known as the sheath of connective tissues which helping in to group muscle fibers into bundles. They are helping delicate cells in protection, and support. It is also playing an important role in transmitting lateral contractile movements in skeletal muscles.
Each muscle compartments carries a bundle of muscle fibers, and this each bundle of muscle fibers is known as fasciculus. Muscle fibers is surrounded with the help of the connective tissues known as endomysium. Bundle of muscle fibers are surrounded with the help of connective tissues known as perimysium.
The connective tissue that encloses a bundle of muscle fibers is called perimysium.
Explanation:The connective tissue that encloses a bundle of muscle fibers is called perimysium. It is a dense and irregular connective tissue that surrounds a group of muscle fibers, forming a bundle known as a fascicle. The perimysium provides support and protection to the muscle fibers, as well as helps transmit the force generated by the muscle contraction.
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The concentration of ions in the chemical environment surrounding the neurons must be tightly regulated for neurons to function properly. Which of the following cells is most responsible for this?A) satellite cellsB) astrocytesC) Schwann cellsD) oligodendrocytes
Answer:
B) astrocytes
Explanation:
Cells other than neurons that play an important role in the normal functioning of nervous system are called Neuroglia or glial cells.
Satellite cells, astrocytes, schwann cells and oligodendrocytes are all examples of glial cells.
⇒Satellite cells provide protection and nutrition to cells in peripheral nervous system ( peripheral nerves and ganglia).
⇒Astrocytes play an important role in central nervous system (brain and spinal cord). They provide protection to neurons, scavenge ions, form the blood-brain barrier and also maintain extracellular environment suitable for neuronal functioning.
⇒Schwann cells are found in the peripheral nervous system and myelinate the axons of neurons.
⇒Oligodendrocytes are found in central nervous system and produce myelin sheath which myelinates (insulates) axons of neurons. Their function is similar to schwann cells but in the central nervous system.
From the above discussion it is clear that the answer is B) Astrocytes as these maintain a suitable chemical environment for the neurons.
Biologists have found more than 500 species of fruit flies on the various Hawaiian islands, all apparently descended from a single ancestor species. When this ancestor colonized the island chain, it found few competitors: Many insect and fly families present in other regions are absent from the isolated Hawaiian Islands. This example illustrates _____.
Answer:
Adaptive radiation
Explanation:
Adaptive radiation occurs when an ancestral species move to a new environment that has various resources that are necessary for survival and also has environmental conditions that would ensure its offspring adapt well over time. In this new environment, the ancestral species would produce offspring with different traits and behaviors that will allow them to survive in this new environment while occupying their various niches. Over a relatively short time, different species arising from the common ancestor would occupy the new environment.
When pink sweet peas were self-pollinated and the sceds were collected and sown, the following flower colors were obtained
Red 34
Pink 76
White 40
Use a chi-squared test to determine whether these results are consistent with the hypothesis that pink flowers are heterozygous for a single pair we predict for our null hypothesis?
A. 9:3:4
B. 3:1:0
C. 1:2:1
D. 1:4:1
The proportions 1:2:1 are consistent with thenull hypothesis that the pink flowers are heterozygous for a single pair.
Option C
Explanation:
Chi square test is used to
(i) Find significant difference in two or more than two proportions
(ii) The goodness of fit between the observed and expected frequency. [tex]X^{2}=\frac{\sum(O-E)^{2}}{E}[/tex]
[tex]X^{2}=\left[\frac{(34-37.5)^{2}}{37.5}\right]+\left[\frac{(76-75)^{2}}{75}\right]+\left[\frac{(40-37.5)^{2}}{37.5}\right][/tex]
= 0.3266 + 0.0133 + 0.1666 = 0.506
5% Critical value = 5.991
Degree of freedom = 2
One character in peas that Mendel studied was yellow versus green seeds. A cross between a homozygous yellow line (YY) and a homozygous green line (yy) will result in F1 plants that are heterozygous (Yy) for this trait and produce yellow seeds.
Answer:
The statement is true.
Explanation:
Gregor Mendel, the Father of Genetics, used pea plants as a model to study inheritance for several reasons, but mainly because they possess a diversity of phenotypic traits, such as different colors and shapes.
Mendel analyzed the inheritance patterns of parental genes in regard to how these genetic traits appeared in the phenotype of the offspring, he categorized these traits as dominant (two capital letters; AA) or recessive (two low-case letters; aa). To test this in the experiments, he selected yellow and green pea plants.
When he crossed yellow and green pea plants, he observed that the first generation exhibited the yellow phenotype. This indicated that the color yellow (YY) was the dominant one, while the green (yy) was, consequently, recessive.
Therefore, if we cross a homozygous yellow line (YY) with a homozygous green line (yy), the result of the First Generation (F1) will result in heterozygous plants with a yellow phenotype as demonstrated in the Punnett Square below:
Y Y
y Yy Yy
y Yy Yy
YY: Yellow
yy: Green
Yy: Yellow
The nasal cavity is divided into left and right portions by the
Answer:
The correct answer will be- nasal septum
Explanation:
The nasal cavity is the hollow space or cavity connected to the two nostrils which allow the inhalation and exhalation of the air into the nose.
The nasal cavity is divided into left and right portion by a cartilaginous bony structure called nasal septum. The nasal septum lies in the central position and divides the nasal cavity into symmetrical portions.
Thus, the nasal septum is the correct answer.
The nasal cavity is separated into left and right parts by a structure known as the nasal septum, composed of a plate of the ethmoid bone, the vomer bone, and septal cartilage. Other key elements of the nasal cavity include the conchae and nasopharynx.
Explanation:The nasal cavity is divided into left and right portions by the nasal septum. This is a flat, midline structure that is comprised of the perpendicular plate of the ethmoid bone, the vomer bone, and septal cartilage. It separates the left and right nasal cavities. The nasal cavity features three bony projections, the superior, middle, and inferior nasal conchae which increase the surface area of the nasal cavity and disrupt the flow of air as it enters the nose. Lastly, the internal nose opens into what is known as the nasopharynx, an airway portion of the pharynx flanked by the conchae and oropharynx.
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Which of the following would be a reasonable experimental strategy to prevent translation of a particular prokaryotic mRNA without targeting the ribosome? Which of the following would be a reasonable experimental strategy to prevent translation of a particular prokaryotic mRNA without targeting the ribosome? Inhibit termination factors. Inhibit the sigma factor. Add suppressor tRNA molecules to the cell. Mutate or remove the Shine-Dalgarno sequence on the mRNA.
Answer:
The correct answer is "Mutate or remove the Shine-Dalgarno sequence on the mRNA".
Explanation:
The Shine-Delgarno sequence is a fragment of bacterial and archaeal messenger RNA that helps to recruit the messenger RNA to the ribosome to initiate protein synthesis by translation. Mutating or removing the Shine-Dalgarno sequence on the mRNA will prevent translation of a particular prokaryotic mRNA. Therefore, this is a reasonable experimental strategy to achieve this effect without targeting the ribosome, but the prokaryotic mRNA.
Compare the two theories regarding the evolution of dinosaurs and then consider the cladogram above. Although the two theories differ on the evolutionary path of dinosaurs, they agree that
Answer:
they agree that dinosaurs, reptiles, and birds had belong to common ancestor.
Explanation:
The reptilians initially emerged before the dinosaurs, but after they never appeared less, the dinosaurs managed to take up the top niches in the food chain. On the other hand, the birds are in fact an evolutionary product of dinosaur diversification. The birds evolved from small bipedal dinosaurs that began to take on a new way of life and appearance in the course of time.
The dinosaurs have not evolved as a separate phylum that does not have close relationships with other animals, but rather shares a common ancestor with reptiles and bird likes.
In bacteria, the antibiotic chloramphenicol prevents amino acids from bonding. The MOST likely reason that bacteria die from treatment with chloramphenicol is because the antibiotic
Answer& explanation:
The mechanism of action of chloramphenicol can be explained as follows:
Chloramphenicol binds to the 50S subunit of the ribosome, inhibiting the protein synthesis of the bacteria, thus having bacteriostatic action (inhibiting the growth of bacteria, preventing their proliferation).
In addition, chloramphenicol can be bactericidal (destroys bacteria) when in high concentrations, or when used against highly sensitive microorganisms, such as Haemophilus influenzae and Streptococcus pneumoniae. The mechanism of action for these bacteria, however, is not yet elucidated.
Haploid Vs Diploid, respond Quick!!!!!
Answer:
Haploid: Haploid is the quality of a cell or organism having a single set of chromosomes. A haploid cell only has one set of chromosomes, and most of the time that refers to the sex cells, either eggs or sperm.
Diploid: Most animal cells and plant cells are diploid. The reason they're diploid is because they got one chromosome from their mother and one chromosome from their father. "Di" means two, of course.
Explanation:
There is a critical transition from a diploid cell to a haploid cell to allow normal reproduction to occur, so that when these two haploid cells come together with a single set of genetic information, they can come together into a zygote (made of when the egg cell and the sperm cell come together) that then reconstitutes a diploid cell, which can then become a new individual.
I don't know much about biology and stuff, but I hope the notes from my notebook help. Good luck!
Answer: Diploid cells contain two comlete sets of chromosomes and haploid only contain half.
Explanation:
While biodiversity includes the number of species in a given area, it also includes:
- overall number of trophic levels in a food web.
- unique phylogenetic lineages.
- abiotic factors that define the community.
- amount of primary productivity.
Answer:
Unique phylogenetic lineages. (Ans. B)
Explanation:
Biodiversity: It is defined as the total species or variety of species present in a place on earth. This variety common measurement is known as species richness, it is defined as the count of species present in an area.
It is helping in to measure variation at the species, genetic, and ecosystem level. Phylogenetic lineage showing the relationship (evolutionary) between different biological species. Their phylogeny is determined by the differences and similarities in their genetic characters.
''Unique phylogenetic lineages.'' is the correct answer.
What is biodiversity?Biodiversity is the total number of species that are present in a place.
Biodiversity helps in the measuring of variation at the species, genetic, and ecosystem level. Phylogenetic lineage shows the relationship between different biological species so we can conclude that ''Unique phylogenetic lineages.'' is the right statement.
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Your objective is to design an observational study to help answer the question_______.What was the determining factor for areas that escaped the worst impacts of the fire, compared to areas that were severely burned?
What type of arthropod appendage is comprised of a single series of segments attached end-to-end
Answer:
The correct answer is - uniramous.
Explanation:
The appendages are present on each body segment of all arthropods. Each segment generally has a pair of end to end appendages. The appendages of the arthropods may be either uniramous or biramous depending on their number of branches in segments.
Uniramous appendages are the appendages that comprise the single series of the end to end attached together, whereas biramous appendages have two branches and each branch has a series of the end to end segments.
Thus, the correct answer is - Uniramous appendages.
Some butterflies can ingest toxic chemicals from the milkweed plants they feed on and then canstore those chemicals in their body. Because toxins stored in the butterflies are toxic to birds, thebirds avoid eating the butterflies. Which of the following is the best explanation for this situation?
A) Any butterfly allele that allowed milkweed toxin storage would be likely to persist becausebutterflies that had it were more likely to survive.
B) Butterflies developed a mutation that led them to be able to store the chemical because theyneeded to avoid being eaten.
C) Milkweed plants wanted the butterflies to ingest the chemical so they would no longer feedon the plant, but the butterflies fooled the milkweed by storing the toxic chemicals.
D) Butterflies that stored the chemicals were never eaten by predators, so those butterfliessurvived.
Answer:
A) Any butterfly allele that allowed milkweed toxin storage would be likely to persist because butterflies that had it were more likely to survive.
Explanation:
Butterflies are natural preys to birds. Over time, some butterflies evolved adaptive strategy such as developing an allele which enables storage of toxin from milkweed as a form of defense mechanism. This stored toxins repel birds from eating the butterflies having this allele giving rise to the survival of these butterflies overtime. Butterflies that had it are likely to be highly favored for survival against predatory birds, while those butterflies without this allele are likely to be heavily preyed upon by birds.
Which of the following correctly displays the sequence of developmental milestones?A) blastula → gastrula → cleavageB) cleavage → gastrula → blastulaC) cleavage → blastula → gastrulaD) gastrula → blastula → cleavage
Cleavage → blastula → gastrula correctly displays the sequence of developmental milestones
Explanation:
In first step of developmental milestone, the zygote undergoes cell cleavage to form a spherical balls of cells, that are known a blastula. This blastula are filled with fluid called blastoderm at the centre. Later the balausta arranges itself in double layer out of which the inner one becomes the zygote and the outer one is placenta. After this stage the blastula folds itself into several layers i.e. germ layers which will give rise to the internal structure of living being. These germ layers are ectoderm, endoderm, mesoderm.
C) The sequence of developmental milestones in embryonic development is cleavage, blastula, and then gastrula.
Initially, the cleavage is the series of mitotic cell divisions of a fertilized egg, or zygote, that leads to a multicellular stage. After cleavage, these cells rearrange to form a hollow ball of cells known as the blastula. The blastula then undergoes a process known as gastrulation, where it folds inward to form a three-layered structure called the gastrula, which will further differentiate into various tissues and organs during the subsequent stages of development.
During embryonic development, unique cell layers develop and differentiate during a stage known as the gastrula stage. These layers, termed germ layers, give rise to the different organs and tissues in the body.
Which term describes a blood transfusion reaction in which an antigen-antibody reaction in the recipient is caused by an incompatibility between red blood cell antigens and antibodies?
Answer:
The correct answer will be- Hemolytic transfusion reaction
Explanation:
Transfusion reactions are called the adverse events which are caused by the transfusion of either one component of the blood or the whole blood.
The transfusion reactions which occur due to the incompatibility reactions of the recipient and the transfused product are called immune-mediated transfusion reaction.
When the incompatibility between the donor red blood cells and the recipient antibodies is observed in the organism, the condition is known as Hemolytic transfusion reaction as it destroys the red blood cells of the donor. This can produce adverse effects on the patient.
Thus, Hemolytic transfusion reaction is the correct answer.
An elephant and a mouse are running in full sunlight, and both overheat by the same amount above their normal body temperatures. When they move into the shade and rest, which animal will cool down faster?
A. The elephant will because it has the higher surface-area-to-volume ratio.
B. The elephant will because it has the lower surface-area-to-volume ratio.
C. The mouse will because it has the higher surface-area-to-volume ratio.
D. They will cool at the same rate because they overheated by the same amount
Answer:
The mouse will because it has the higher surface-area-to-volume ratio.
Explanation:
The living organisms maintain their homeostasis by maintaining their internal constant environment as external environment changes. These organisms are known as exothermic animal.
The surface area to volume ratio in case of living organisms plays an important role. The small species has high surface area to volume ratio as compared to the larger species. The diffusion, cooling and other process is faster in the small size species. The mouse body will get cool faster than elephant species.
Thus, the correct answer is option (3).
Thirty people are selected for a long-term mission to colonize a planet many light-years away from Earth. The mission is successful and the population rapidly grows to several hundred individuals However, certain genetic diseases are unusually common in this group, and the group's gene pool is quite different from that of the Earth population they have left behind. Which of the following phenomena has left its mark on this population?a.founder effectb.adaptive effectc.high rates of mutationd.natural selection
Answer:
The correct answer will be Option- founder effect
Explanation:
The founder effect is the effect observed in a population caused by the loss of the genetic variation. The genetic variation is lost as a result of the establishment of the new population caused by the migration of the few numbers of individuals from a larger population.
This loss of genetic variation leads to variation in the genotype and phenotype of the newly established population.
Since in the given question the gene pool of the new population on the new planet is different from the parent population leads to a phenomenon called founder effect.
Thus, the founder effect is the correct answer.
Parents with the dominant phenotype cannot have offspring with the recessive phenotype.
Answer:
False, they can have recessive phenotype
Explanation:
A phenotype is a viable characteristic an individual presents as a consequence of the interaction between its environment and its genotype.
This doesn’t necessarily means that the individual’s aleles are both dominant (homozygotes), they could have one dominant and one recessive gen (heterozygotes), meaning that, if the another parent is homozygote with both recessive aleles the offspring could heritage homozygote recessive aleles that will result in a recessive phenotype.
You can observe in the image I added a punnet square that exemplifies the scenario. You can see that the offspring has 1/2 probability to have recessive phenotype.
I hope you find this information useful and interesting! Good luck!
Answer:
75% and 25%
Explanation:
A part of the promoter found in Archaea and Eukaryotes, called the TATA box, is said to be highly conserved in evolution. What could this indicate?A. The sequence evolves very rapidly.B. The sequence does not mutate.C. Any mutation in the sequence is selected against.
Answer:
The sequence does not mutate.
Explanation:
The conserved sequences may be defined as the identical or the similar DNA sequences that shows similarity in different group of organism. TATA box sequences is the example of conserved sequences.
These conserved sequences has been maintained by the phenomena of the natural selection. These sequences remain conserved throughout the evolution process. The conserved sequences cannot be mutated easily and present from the different geologic time.
Thus, the correct answer is answer is option (B).
To see patterns in the data from an experiment like this, it is helpful to graph the data. A bar graph is used instead of a line graph because each type of liver cell was independent of the others. But first, you must determine which variable should go on each axis of the graph.
What variable did the researchers intentionally vary in the experiment, and what are the units for this variable?
Answer:
From the information you provided, the information intentionally varied is the type of liver cells and there should not be any units for this variable unless the liver cells were categorised by a quantitative feature. The y axis would be the axis of the dependent variable measured and the x axis would be the axis of the independent variable measured.
Explanation:
Gender role socialization... is the process by which social institutions shape expectations of acceptable behaviors for men and women. makes anti-discrimination and equal pay legislation more effective. results in men preparing for non-traditional jobs for men. None of the above.
Answer:
gender role socialization is the process by which social institutions shape expectations of acceptable behaviours for men and women
Gender role socialization is the process by which societal expectations of acceptable behaviors for men and women are shaped, involving agents like family and media. It enforces stereotypes and limits personal freedom, but understanding it can lead to more inclusive societies.
Gender role socialization is the process by which social institutions shape expectations of acceptable behaviors for men and women. This includes how individuals are taught to behave, perceive, and interact within their societal roles based on their gender. The primary agents of gender socialization are family, education, peer groups, and mass media, each reinforcing gender roles and creating normative expectations for gender-specific behavior. This process begins early in life, leading individuals to often subconsciously conform to these roles, believing their actions to be natural rather than the result of societal constructs.
Gender socialization plays a critical role in shaping the lives of individuals by dictating the behaviors, attitudes, and opportunities deemed appropriate based on one's gender. Unfortunately, this often enforces stereotypes and limits personal freedom and expression, contributing to a cycle of gender-based discrimination and inequality. Understanding and challenging these constructed roles can lead to more inclusive and diverse societies, where individuals are valued for their unique abilities rather than their adherence to prescribed gender roles.
The phylum Cycliophora was discovered in 1995. They are tiny organisms that live in large numbers on the outsides of the mouthparts and appendages of lobsters. The feeding stage permanently attaches to the lobster via an adhesive disk and collects scraps of food from its host's feeding by capturing the scraps in a current created by a ring of cilia. The body is saclike and has a U-shaped intestine that brings the anus close to the mouth. Cycliophorans are coelomates, do not molt (though their host does), and their embryos undergo spiral cleavage. Basing your inferences on information in the paragraph, to which clades should cycliophorans belong?
A) Eumetazoa and BilateriaB) Eumetazoa and LophotrochozoaC) Deuterostomia and EcdysozoaD) Deuterostomia and Lophotrochozoa
Answer:
The answer is letter B. Eumetazoa and Lophotrochozoa
Explanation:
Eumetazoa and Lophotrochozoa
Because the phylum Cycliophora neither helps or harms its lobster host.
. The trait that would be least useful in a phylogenetic analysis would be one that A) is detectable only in observations of early development. B) involves genetically inherited behaviors. C) is altered easily by small changes in diet. D) can be studied only in museum specimens. E) is heritable but is determined by many genes.
Answer:
A trait that is altered easily by small changes in diet.
Explanation:
The phylogenetic tree explains the evolutionary relationship between the organisms. The phylogeny of the organisms will depend on the difference and similarities in their genetic or physical characters.
The traits that are used in phylogeny must be constant and present in the ancestors or in atleast a group. The trait that can be easily modified or changed cannot be used for the study of the evolutionary relationship. Hence, trait which is altered by diet cannot be used in phylogenetic analysis.
Thus, the correct answer is option (C).
What are the reasons for the several day delay in a primary response. Infection______. A. transport to secondary lymphoid tissue B. antigen processing and presentation C. small initial # of lymphocytes specific for the antigen D. proliferation and differentiation.
Answer:
The correct answer is D. proliferation and differentiation.
Explanation:
Primary immune response occurs due to the first exposure of an antigen to the immune system. The primary immune response is generally delayed by many days because it takes time for B and T cells to become cloned and to proliferate and differentiate.
Then after several days of proliferation and differentiation of activated T and B cells, T cells become effector T cells and B cell becomes plasma cells which then eliminates the antigen. Memory B and T cells are also produced during this process which helps in generating a quick immune response during the second and subsequent exposure of that antigen.
So the correct answer is D. proliferation and differentiation.
Some characteristics of DNA are shared between all living organisms, whereas other characteristics of DNA differ between organisms. Classify DNA characteristics as either being a universal attribute of DNA or an attribute of DNA that is unique to particular individuals or species.
Explanation:
Universal: made up of nucleotides (A T C G), forms codons of three nucleotides, each encodes an amino acid
Species or Individual: size of the genome, sequence of DNA
The nucleus is a large membrane-bound organelle that houses the genetic information, DNA, in the cell. Sequences of DNA make up genes which can have different forms called alleles and comprise the genotype. DNA is transcribed into mRNA and later translated into amino acids which are linked together by rRNA to form proteins. These proteins, when expressed, are referred to as an organism's phenotype.
Further Explanation:
All the genetic information within the eukaryotic cell is stored within the nucleus as helical DNA. This DNA is tightly wound around histones as chromosomes. Chromosomes within the nucleus is unwound, unzipped and read by enzymes in a complex series of steps known as transcription. The message on DNA, called genes is copied by RNA polymerase, to form mRNA complementary sequence to that of the DNA strand. These are then translated into proteins in ribosomes.
Large chains of monomers form biological macromolecules which carry out many essential functions in the body these can include nucleic acids, carbohydrates, proteins and lipids. These are organic molecules, meaning they're ringed or long-chain Carbons bonded to the elements oxygen (O), hydrogen (H), nitrogen (N) and phosphorus (P).
Proteins are structural support molecules comprised of long chains of amino acids joined via peptide (CONH) bonds; these are 20 specific units that are arranged into several macromolecules. Amino acids are absorbed through digestion and are incorporated into the body’s cells to make up organs muscles signal molecules and an alternative energy source.
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What general statement can be made about the areas a radius vector for these satellites covered in each one hour period?
The speed of satellite is constant and it is able to cover equal distance in each 1-hour period.
Explanation:
Satellite is artificial or natural body which revolves around any planet. Our earth has a natural satellite known as moon. There are a lot of artificial satellites which revolve around the earth continuously. The time period of all the satellites are fixed. They are designated and designed to have uniform circular motion around the earth.
This satellite is very useful for the earth as it transmits signals from one corner of the earth to the other corner. some of the satellite are known as geostationary satellite which revolves around the earth with the same speed as of the earth.
Only the fibrous layer can be observed in its entirety from the superficial surface of the cow eye. True or False
Answer:
True
Explanation:
Three layers are found in a given mammalian eye and since cow is also a mammal the same applies to it.
The three layers are as follows :
1. Fibrous layers - it is the outermost layer that consists of the sclera and the cornea.
2. The vascular layer - it is the middle layer and is vascularized. it consists of the iris, the ciliary body, and the choroid.
3. The neural layer- it is the innermost layer that consists of the retina.
In a cow's eyes, these three layers are present however only the uppermost fibrous layer is visible from the superficial surface because the vascular and the neural layers lie deep to the fibrous layer.
Answer:
True
Explanation:
The fibrous layer is the external layer of eyeball wall. The fibrous layer is a connective tissue that is not connected with blood supply thus it is avascular tissue. This tissue contains eyeball contents. The opaque sclera consist of around 90% of posterior side of fibrous layer. The cornea consist of around 10% of fibrous anterior portion of eye. The layers like neural and fibrous are deep. Thus, it is not possible to observe these layers. So, only the fibrous layer can be observed in its entirety from the superficial surface of the cow eye.
What were the first hominins? What was the evolutionary fate of the first hominins?
Drag the descriptions to the appropriate hominin lineages.
A) Pre-australopithecinerobust.
B) Australopithecinesgenus Homo.
Answer:
A) Pre-australopithecinerobust.
B) Australopithecinesgenus Homo.
Explanation:
Pre-australopithecinerobust.
The few findings indicate that he walked with his back straight, but the shape of the foot, with the big toe directed inward (as in the hands) instead of being parallel to the others, indicates that he should walk leaning on the outside of his feet and he couldn't travel great distances
Australopithecinesgenus Homo.
The first hominids that are certain that they were completely biped are the members of the Australopithecus genus, this type of hominin thrived in the wooded savannas of East Africa between 4 and 2.5 million years ago with remarkable ecological success, as evidenced by the radiation he experienced, with at least five different species scattered from Ethiopia and Chad to South Africa.
Oxidative phosphorylation is the third step in cellular respiration. It is composed of two smaller steps (electron transport chain and chemiosmosis). What molecules are donating their energy to power the proteins in the ETC?
Answer:
NADH and FADH2
Explanation:
Oxidative phosphorylation is the last step of cellular respiration involving two smaller steps; Electron transport chain (ETC) and chemiosmosis.
ETC is a series of proteins and organic molecules present in the cristae of the mitochondria. Electrons are passed from one member of the transport chain to another in a series of reduction-oxidation reactions (redox). Energy released is captured as a proton gradient.
All the electrons that are supplied into the transport chain are donated by NADH and FADH2 molecules (reduced electron carriers) produced in the previous stages of respiration. As the electrons are passed down the chain, they move from a higher to a lower energy level, releasing energy in the process. The released energy is used by several of the protein complexes to pump protons from the matrix of the mitochondria to the intermembrane space, forming a proton gradient.
The electrons donated by NADH are at a higher energy level i.e. NADH is a very good donor of electrons in redox reactions. This attribute allows NADH to transfer its electrons directly to Complex I, where energy is released and the complex uses this energy to pump protons across the membrane.
FADH2, on the other hand, is not a good donor of electrons. Thus, its electrons are at a lower energy level, making it unable to transfer its electrons to ComplexI. It feeds them through Complex II instead, which does not pump protons across the membrane.
This factor (Complex I bypass) causes FADH2 molecules to contribute less to the proton gradient than NADH molecules.
N.B: the energy stored in the proton gradient is subsequently used to produce ATP in Chemiosmosis.
Final answer:
In the electron transport chain part of oxidative phosphorylation, the molecules NADH and [tex]FADH_2[/tex] donate high-energy electrons to power the protein complexes and create ATP. These electron carriers are produced during earlier steps of cellular respiration.
Explanation:
Oxidative phosphorylation is the third and final step of aerobic cellular respiration and it includes two processes: the electron transport chain (ETC) and chemiosmosis. In the ETC, energy is provided by two molecules, NADH and [tex]FADH_2[/tex], which are the reduced forms of the electron carriers NAD+ and FAD.
These molecules are produced during earlier stages of cellular respiration and donate their high-energy electrons to power the protein complexes within the ETC. As the electrons flow through the chain, they release energy used to pump protons across the mitochondrial membrane, creating an electrochemical gradient.
During chemiosmosis, the accumulated protons flow back into the mitochondrial matrix through an enzyme called ATP synthase, which synthesizes ATP from ADP and inorganic phosphate. The flow of protons provides the energy necessary for ATP production, culminating in the highly efficient generation of ATP, essential for cellular processes.
Which trophic level generates the most dead organic material in most ecosystems?
Answer:
1st trophic level
Explanation:
Trophic levels are each of the sets of organisms in an ecosystem that obtain matter and energy in the same way, so they occupy an equivalent place in the food chain.
The energy that living beings need to perform vital functions (nutrition, relationship and reproduction) comes from the Sun. Plants are responsible, through photosynthesis, for transforming inorganic matter into organic. This matter and energy will pass to the rest of the organisms in the ecosystem, such as herbivorous and carnivorous animals. Finally, the decomposing organisms will be responsible for breaking down this organic matter into inorganic, closing the cycle so that it can be restarted.
Therefore, we can distinguish three trophic levels:
- Producing organizations (autotrophs) or 1st trophic level
- Consumer organisms (herbivores, carnivores, scavengers).
- Decomposing and transforming organisms (break down organic matter into inorganic).
Producing organisms are autotrophs (plants, algae and some bacteria). They are capable of manufacturing their own organic matter from inorganic matter (water, mineral salts and carbon dioxide) and the energy of the sun, which is why they are called producers.
Producing organisms constitute the lowest trophic level, being the basis on which the higher levels are based. They are the only ones that, through photosynthesis, are capable of capturing solar energy and transforming it into chemical energy. They are also the ones that generate the greatest amount of dead organic matter in the ecosystem.