Answer:
utilitarian conservation or Pragmatic resource conservation
Explanation:
As per the utilitarian conservation or Pragmatic resource conservation, the resources must be utilized to their full capacity up to the possible longest period of time for the greatest good of all.
Therefore, even if the leaves become dead they can be used one more time for preparing compost of fertilizer thereby putting it to greatest use till its greatest number of times.
An important challenge to traditional (pre-1860) ideas about species was the observation that seemingly dissimilar organisms, such as hummingbirds, humans, and whales, have similar skeletal structures. This most directly suggested to biologists that ____________.
a) only the best-adapted organisms can survive
b) advantageous changes can be passed along to offspring
c) most evolution occurs rapidly following a mass extinction
d) dissimilar organisms might have evolved from a distant, common ancestor
e) all of the above
Answer:
Option-D
Explanation:
One of the common belief before the Darwin about the species was that the species can change over time but they do not evolve into another species that is the species do not share the common ancestor.
The collected evidence that the similarity in the skeletal system of the distantly related species like in the humming bird, the whales and the humans suggested that they have evolved from the common ancestor. This observation was the challenge to the pre- Darwinian ideas.
Thus, Option-D is the correct answer.
6. Evolution explains both the unity and diversity of life. Explain how evolution can account for both why anoles and finches share certain traits and also why they differ. [2 pts]6. Evolution explains both the unity and diversity of life. Explain how evolution can account for both why anoles and finches share certain traits and also why they differ.
Evolutionary processes through natural selection acting on genetic variation explain the unity and diversity observed among species. Convergent evolution results in similar traits in different species, while divergent evolution leads to differences within groups that have common ancestors. Mutations drive the genetic variation that fuels these evolutionary processes.
Explanation:Evolutionary processes account for both the commonalities and differences between species such as anoles and finches. The theory of evolution is underpinned by the idea that all life is related and that modifications occur over time through natural selection acting on genetic variation.
On the one hand, convergent evolution explains how different species may develop similar traits as a result of adapting to similar environmental pressures. This leads to the unity of various life forms that look superficially similar due to similar selection pressures even though they might not be closely related genetically.
On the other hand, divergent evolution or adaptive radiation accounts for the diversity we see within groups of closely related organisms. Even though species like anoles and finches may share a common ancestor, the different environmental niches they occupy have pushed them to evolve distinct traits.
These differences highlight the adaptability and variation within species that result from the differential survival and reproduction of individuals with favorable traits. As environments change or as species spread into new habitats, natural selection favors different traits, leading to further diversification.
Variation within populations is driven by mutations, creating the genetic differences that are the raw material for evolution. The consistent yet various biological structures, behaviors, and adaptations seen in the living world all illustrate the balance of unity and diversity explained by evolutionary theory. It is this balance that has led to the rich tapestry of life we observe around us today.
A specialization of the stomach that aids in grinding for animals that lack teeth is the ____.
a. esophagus
b. cloaca
c. gizzard
d. crop
e. rumen
Answer:
C. gizzrd
Explanation:
Final answer:
The correct answer is the gizzard (option c), which is a specialized stomach that grinds food in animals, such as birds, that do not have teeth for chewing.
Explanation:
The specialization of the stomach that aids in grinding for animals that lack teeth is the gizzard. Animals such as birds possess a gizzard that allows them to grind their food, as they do not have teeth to masticate. In the avian digestive system, food passes from the esophagus to a pouch called a crop, which stores food, then to the proventriculus where it is initially processed with digestive juices. The partially digested food next enters the gizzard, where it is ground into smaller pieces. Birds may also swallow stones or grit, which are stored in the gizzard to aid in the grinding process.
Which of the following parts of the nervous system would carry messages from one’s sore knee to the brain and spinal cord to alert the person to stop running and rest?
Answer:peripheral
somatic
Explanation:
somatic nervous system carried information from the joints,muscles, and skin to the spinal cord and brain
"Explain what an enzyme cofactor is and discuss the types of molecules that can act as cofactors (prosthetic groups) and why these are particularly important as electron acceptors."
Answer:
A cofactor is a not proteic substance that is required to an enzyme activity. Cofactors can either be organic compunds, like vitamins, or inorganic compounds, like the metallic elements, iron, zinc, magnesium, cooper, among others. If the cofactor is removed from a complete enzyme (holoenzyme), the protein component (apoenzyme) no longer has catalytic activity.
In some enzymes the cofactors act for the substrate binding to the active site. In other, like dehydrogenases, which transfer electrons from the substrate to an electron carrier, the carrier used depends on the reaction taking place. Common electron acceptors used by this subclass are NAD+, FAD, and NADP+. Electron carriers are reduced in this process and considered oxidizers of the substrate. Electron carriers are coenzymes that are often referred to as redox cofactors.
Explanation:
An examiner who discovers unequal movement or uneven gluteal skinfolds during the Ortolani maneuver does what?
Answer:
B. alerts the physician that the infant has a dislocated hip.
Explanation:
An examiner who discovers unequal movement or uneven gluteal skinfolds during the Ortolani maneuver would alert the physician that the infant has a dislocated hip. This can be said because the Ortolani maneuver is a technique that is used in order to check hip integrity, and if unequal movement is detected during this technique it suggests that the hip is dislocated.
The Ortolani maneuver is used to detect hip dislocation or dysplasia in infants. If unequal movement or uneven gluteal skinfolds are found, the examiner performs certain movements to assess the state of the hip and may recommend further diagnosis.
Explanation:The Ortolani maneuver is an examination technique in the field of
medicine
that is utilized to detect hip dislocation or congenital hip dysplasia in infants. If during the Ortolani maneuver, the examiner discovers unequal movement or uneven gluteal skinfolds, it can be a sign of a dislocated hip. In such a scenario, the examiner moves the back of the lower legs up and back toward the buttocks, as if ((the infant)) is kneeling. The maneuver involves assisting in moving the infant's thigh diagonally upward and outward. The examiner might also move the thigh down and back, or twist the thigh and the lower leg inward. Upon detecting this abnormality, the examiner will likely recommend further diagnostic procedures to confirm the diagnosis and propose suitable treatment options.
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A female fly, full of fertilized eggs, is swept by high winds to an island far out to sea. She is the first fly to arrive on this island and the only fly to arrive in this way. Thousands of years later, her numerous offspring occupy the island, but none of them resembles her. There are, instead, several species, each of which eats only a certain type of food. None of the species can fly and their balancing organs (halteres) are now used in courtship displays. The male members of each species bear modified halteres that are unique in appearance to their species. Females bear vestigial halteres. The ranges of all of the daughter species overlap.If the malesʹ halteres have species-specific size, shape, color, and use in courtship displays, and if the speciesʹ ranges overlap, then the speciation events may have been driven, at least in part, by which of the following?
A) autopolyploidy
B) allopolyploidy
C) species selection
D) sexual selection
E) habitat differentiation
Answer:
The correct answer is option D) "sexual selection".
Explanation:
Sexual selection is a type of natural selection at which species of one sex chose their biological mates based on specific traits that represent an advantageous trait for the species. In this case, if the males halteres are used in courtship displays and the females select them in base of its size, shape and color, the speciation events may have been driven, at least in part, by sexual selection.
The correct answer is sexual selection.
The "distance" between two linked gene pairs can be expressed as a percentage. Name the unit based on percent recombination that was created in honour of the scientist who pioneered the use of fruit flies for genetic research?
Answer:
Centimorgan
Explanation:
Centimorgan is a unit that measures the recombinant frequency. When we say that recombinant frequency is 1 then it means that there is 1% chance of separation of marker between two genetic locus when a cross is carried out in the single generation. This unit was devised as a token of remembrance for geneticist Thomas Hunt Morgan who was also a noble prize winner.
There are one million base pairs in one centimorgan
Final answer:
A centimorgan (cM) is the unit of genetic distance that reflects the percent recombination between two genes, named in honor of Thomas Hunt Morgan for his contributions to genetic research using fruit flies.
Explanation:
The unit based on percent recombination that was created to honor the scientist who pioneered the use of fruit flies for genetic research is called a centimorgan (cM). This unit reflects the genetic distance between two genes based on their recombination frequency. A centimorgan corresponds to a 1% chance that a crossing over event will occur between two alleles during meiosis. Therefore, if two genes exhibit a recombination frequency of 1%, they are said to be 1 cM apart on a chromosome. This unit was named after Thomas Hunt Morgan, the scientist who conducted extensive research using fruit flies. Genetic maps constructed using centimorgans show the relative positions of genes on a chromosome.
_______ is the study of how living things interact with each other and their environment
Answer:
EcologyExplanation:
Ecology is the study of biotic and abiotic factors of an ecosystem and the interactions between them.
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Ecology is the field of biology that deals with the interactions of living things with each other and their environment. It includes studying relationships between organisms and their surroundings and trying to understand the balance of life in the natural world.
Explanation:Ecology is the study of how living things interact with each other and their environment. This can involve examining the relationships and interactions between organisms, ranging from microscopic bacteria to large mammals, and their surroundings.
For example, ecologists might explore how tree populations impact the soil in a forest, how predators influence the behavior and population of their prey, or how pollution in a stream affects fish populations.
Overall, the goal of ecology is to understand the balance of life in the natural world.
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is not considered separate species because organisms of different breeds
can mate and produce fertile offspring.
Breed
Phenotype
Genotype
Fitness
Breed is not considered separate species because organisms of different breeds can mate and produce fertile offspring.
BreedExplanation:
A breed is a particular gathering of residential creatures having homogeneous appearance (phenotype), homogeneous conduct, and additionally different attributes that recognize it from different life forms of similar species. Comprehensively, various species can't interbreed and create solid, ripe posterity because of hindrances called systems of regenerative confinement.
These obstructions can be part into two classifications dependent on when they act: prezygotic and postzygotic. Generally, various species don't mate. Be that as it may, when they do, their posterity will be what are called cross breeds.
Which types of decisions are more prevalent at lower organizational levels? Group of answer choices Structured decisions Procedural decisions Unstructured decisions Semistructured decisions Operational decisions
Answer:
Option A, structured decisions
Explanation:
In lower level organizations, the processes are already in place to tackle with any situation and hence structured decisions can be easily taken. Since the problems in a lower organization recur again and again, therefore, processes and procedures need to be in place to handle them in an organized manner as a part of routine work. Every time such problem arises, it is to be treated in a definite manner instead of treating as new each time. For example – HR processes in a company are categorized as structured problem which require a structured decision.
Hence, option A is correct
Final answer:
Lower organizational levels primarily encounter operational decisions, which are routine and often programmed, enabling an automated response to common situations.
Explanation:
The type of decisions that are more prevalent at lower organizational levels are operational decisions. Operational decisions refer to choices made daily that help the organization run smoothly. These decisions often involve structured decision-making processes and can be considered as programmed decisions, because they occur frequently enough that employees develop automated responses. An example of this would be a server at a restaurant deciding whether a customer complaint legitimizes offering a free dessert based on a policy set by management. In contrast, strategic decisions, related to setting the organization's course, are made at higher organizational levels.
Which statement about an action potential is true? 1. It "skips" over segments of myelin, hopping from one node of Ranvier to the next. 2. It is a neurotransmitter that relays messages from motor neurons to muscles, enabling movement.3. It defends the brain from infection and inflammation.4. It has a nucleus containing DNA.
Answer:
1. It "skips" over segments of myelin, hopping from one node of Ranvier to the next.
Explanation:
The action potential is the electrical signal. It is produced in neurons and muscle cells to propagate the nerve impulse. It is fired when the membrane of a neuron is depolarized. Myelinated axons exhibit saltatory conduction of action potential. This means that the action potential is propagated from one node of Ranvier to the next while skipping the in-between myelinated region. This occurs since the voltage-gated channels are mainly concentrated at the nodes of Ranvier. Therefore, the action potential is mainly carried at nodes where Na+ and K+ flow across the membrane.
Hector and his family came to the United States from Cuba last year. Hector speaks only Spanish and seems unable to learn English despite extended help from an ELL teacher. He is failing all subjects in second grade except for Art and P.E. He was recently evaluated for the possibility of an intellectual disability. The school psychologist administered an intelligence test in Spanish. Scores indicate that Hector has significant cognitive delays. Based on the findings, the IEP team is recommending that Hector receive special education services as a student with an intellectual disability. Did Hector receive a nondiscriminatory evaluation as required by IDEA?
Answer:
Yes he did
Explanation:
Non-discriminatory evaluation: An IDEA precept that allows schools to assess students equally in order to ascertain whether they have a disability, if so, which one and how severe.The assessment has to be conducted in a culturally responsive manner to facilitate fairness.
The students in Ms. Hill's science class were investigating the properties of water. Juan dipped a finger in a beaker of water; Sally dipped her finger in a beaker of alcohol. They both streaked the lab bench with the liquids on their fingers and watched to see which liquid disappeared or evaporated first. The alcohol evaporated quickly, leaving the water streak on the lab bench for several minutes. What unique property of water was illustrated by this simple experiment? A) buoyancy B) specific heat C) surface tension D) capillary action
Answer:
B) specific heat
Explanation:
The specific heat of a substance is how much heat per unit mass it need to elevate its temperature by one degree Celsius. Its units are joule per kelvin and kilogram, J/(K kg). In the example given you can observe that water need more heat in order to evaporate compared to the alcohol.
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Answer: Specific Heat
A change in the responsiveness of the sensory system based on the average level of surrounding stimulation is called sensory _____.
Answer:
Sensory adaptation.
Explanation:
An exposure to constant or prolonged stimulus will slowly decrease our response.For example, when we rested our arm or hand on the table then the surface of the table will abruptly feel against our hand.Sensory adaptation helps us in daily life work by decreasing our response to constant stimulus that's why we give our attention to other environmental aspects. If our response will remain constant to prolonged stimulus then we can't detect new or important environmental aspects.A vestigial-winged, hairy male is crossed with a wild-type female, homozygous at both genes. This F1 generation is crossed to produce the F2 generation. Which of the following are accurate expectations regarding the F1 or F2 generations resulting from this cross? Choose all reasonable answers. Please draw the full 4x4 Punnett Square to answer this question.a.The expected proportion of F2 individuals which are homozygous recessive at both genes is 1/16b.Most of the F2 generation will have the normal phenotypes for both genesc.The expected proportion of F2 individuals with at least one recessive phenotype (either hairy or vestigial wings) is 8/16d.All of the F1 generation will have the normal phenotypes for both genese.There will be no homozygous individuals in the F1 generation
Answer:
The expected proportion of F2 individuals which are homozygous recessive at both genes is 1/16
All of the F1 generation will have the normal phenotypes for both genes
There will be no homozygous individuals in the F1 generation
Most of the F2 generation will have the normal phenotypes for both genes
Explanation:
A winged hairy male is crossed with a wild type female which is homozygous
Let the allele for vestigial trait be v
allele for wild trait be w
allele for hairy trait be h
Allele for non hairy be n
The genotype of parents would be
vvhh * wwnn
Thus in F1 generation all the offsrping will have normal phenotypes for both genes
In F2 generation
vwnh * vwnh
Out of 16 offspring only one wil be homozygous recessive i,e
wwnn
Rest all 15 will have normal phenotypes.
Hence, the correct answer is
The expected proportion of F2 individuals which are homozygous recessive at both genes is 1/16
All of the F1 generation will have the normal phenotypes for both genes
There will be no homozygous individuals in the F1 generation
Most of the F2 generation will have the normal phenotypes for both genes
When true-breeding or homozygous individuals that differ for a certain trait are crossed, all of the offspring will be heterozygotes for that trait. If these heterozygous offspring are self-crossed, the resulting F2 offspring will exhibit a ratio of three dominant to one recessive.
Explanation:When true-breeding or homozygous individuals that differ for a certain trait are crossed, all of the offspring will be heterozygotes for that trait. If the traits are inherited as dominant and recessive, the F1 offspring will all exhibit the same phenotype as the parent homozygous for the dominant trait. If these heterozygous offspring are self-crossed, the resulting F2 offspring will be equally likely to inherit gametes carrying the dominant or recessive trait, giving rise to offspring of which one quarter are homozygous dominant, half are heterozygous, and one quarter are homozygous recessive. Because homozygous dominant and heterozygous individuals are phenotypically identical, the observed traits in the F2 offspring will exhibit a ratio of three dominant to one recessive.
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What kind of animals are best suited to life in a desert? A. Animals that estimate during hot weather B. Animals that nest in tall trees C. Animals that hibernate during winter D. Animals that have thick layer of blubber or fur
Some animals have evolved salt glands, a physical adaption that permits salt to be secreted without causing water loss. Other morphological modifications achieved by desert animals include the absence of sweat glands and the concentration of urine. Thus, option A is correct.
What animals are best suited to life in a desert?All organisms must be able to change with their environment in order to live.This entails adapting in order to survive the ecosystem's climatic conditions, predators, and other species that compete with them for resources like food and habitat.
Evaporative cooling is the main strategy for bringing a hot bird or mammal down. A surface cools when water vapour escapes from it.
Animals like camels, rats, and snakes that can handle arid climates and lengthy periods without water.
Therefore, Animals that estimate during hot weather.
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The theory that organisms can arise from inanimate matter is called Choose one: A. spontaneous generation. B. endosymbiosis. C. fermentation. D. germ theory.
Answer:
A. Spontaneous Generation
Final answer:
a) Spontaneous generation is the outdated theory that living organisms can arise from non-living matter, which has been replaced by the theories of biogenesis and Cell Theory, affirming that life comes from pre-existing life.
Explanation:
The theory that organisms can arise from inanimate matter is called a) spontaneous generation. This theory, which dates back to ancient Greeks like Aristotle, suggested that living organisms could spontaneously emerge from non-living materials. Flies were thought to arise from rotting flesh, and mice from wheat. However, this theory was disproved by experiments that proved living organisms come from other living organisms, a concept known as biogenesis. The Cell Theory, which is widely accepted today, states that all cells come from pre-existing cells, thus supporting biogenesis over spontaneous generation.
Which of the following correctly describes polyphyletic groups?
organisms that share all of the same traits
organisms that share a common trait, inherited from a common ancestor
organisms that share a common ancestor, but leave out some of the descendants
organisms that happen to share a common trait, even though they evolved
Answer:organisms that happen to share a common trait, even though they evolved
Explanation: polyphyletic groups have similar characteristics but
that have been grouped together
They do not share an immediate common ancestor.
Polyphyletic group is characterized by organisms that happen to share a common trait.
Polyphyletic groups are groups of organisms that include species with similar characteristics that have evolved from more than one ancestor. These characteristics may appear to be similar due to convergent evolution rather than deriving from a common ancestor.
The cell walls of bacteria, fungi, and plant cells and the extracellular matrix of animal cells are all external to the plasma membrane. Which of the following is a characteristic common to all of these extracellular structures?
A) They must block water and small molecules in order to regulate the exchange of matter and energy with their environment.
B) They must permit information transfer between the cell's cytoplasm and the nucleus.
C) They must provide a rigid structure that maintains an appropriate ratio of cell surface area to volume.
D) They are constructed of polymers that are synthesized in the cytoplasm and then transported out of the cell.
E) They are composed of a mixture of lipids and carbohydrates.
Answer:
D) They are constructed of polymers that are synthesized in the cytoplasm and then transported out of the cell.
Explanation:
Proteins, complex carbohydrates, lipids are important polymer components of the cell wall of bacteria, fungi, and extracellular matrix of animal cells. These all structures are located outside the plasma membrane but the raw material required to make these structures are synthesized inside the cell in the cytoplasm and exported outside the cell membrane by transporters.
Therefore cell walls of different organisms and extracellular matrix of animal cells are constructed of polymers that are produced in cytoplasm and are transported outside the membrane.
If a cell with 12 chromosomes undergoes mitosis, how many daughter cells result and what is the chromosome number in each daughter cell?
Answer:
The answer to your question is below
Explanation:
Mitosis is a kind of sexual reproduction where a mother cell gives rise to two identical cells in which the initial number of chromosomes maintains the same.
So in this question, the products will be 2 daughter cells in which each cell will have 12 chromosomes.
If the surface barriers of innate immunity, such as the skin or mucous membranes are breached, the second line of defense in innate immunity is (are) the:
Answer:
If the surface barriers of innate immunity, such as the skin or mucous membranes are breached, the second line of defense in innate immunity is (are) the: lymphocytes
Explanation:
The lymphocytes direct and regulate immune responses. Specifically, B lymphocytes produce antibodies to fight against bacteria, viruses and invading toxins. T lymphocytes destroy the body's own cells that have been infected by viruses or that are cancerous.
You are watching a televised debate on evolution. One of the participants repeatedly states that evolution is a "scientific theory," and as such is unsupported by any evidence. What is wrong with this statement?
Answer:
Answer : Scientific theories are rigorously supported by numerous studies, and are hypotheses that, even up till date, have never been disproved.
Explanation:
Scientific theory can be explained as a theory that was highly supported by facts. This means that , it is continuously or repeatedly confirmed by observation and experiment by scientists.
Evolution can be described as changes that occur in the heritable characters over a period of time. This usually occurs through natural selection.
In this case, evolution is known to be a scientific theory, because it involved careful observations and confirming experiments by scientists.
The statement that evolution is an unsupported 'scientific theory' is incorrect, as in science, a theory is a robust explanation backed by substantial evidence. The theory of evolution, in particular, is supported by extensive research and is widely accepted by scientists. Critics often misunderstand the term 'theory' in a scientific context, leading to misconceptions about the supporting evidence for evolution.
Explanation:The statement that evolution is a "scientific theory" and is unsupported by any evidence is an incorrect assertion. The confusion arises from the difference between the common use of the term "theory" and its scientific meaning. In science, a theory is a well-substantiated explanation of some aspect of the natural world that has been repeatedly confirmed through observation and experimentation. The theory of evolution is similarly supported by a vast body of evidence from various fields such as genetics, paleontology, and comparative anatomy, making it one of the most reliable and accepted explanations in science.
Furthermore, the concept of evolution is well-founded and upheld by the scientific community. A Pew Research poll showed that 97% of scientists agree with the principle of species evolving over time. It's incorrect to suggest that the theory is still controversial among biologists, as it has robust experimental and observational evidence.
When critics of evolution dismiss it as "just a theory," they are misusing the term and neglecting the large amount of evidence that supports it—evidence that encompasses fossil records, DNA sequence comparisons, and the observation of natural selection in action. Such critiques often stem from a misunderstanding of scientific language and do not reflect the consensus within the scientific community.
All of the cells in the human body contain the same genes. How do cells have different morphologies and functions when they contain the same genetic information?
Vertebrate immune responses involve communication over short and long distances. Which of the following statements best helps explain how cell surface proteins, such as MHC proteins and T cell receptors, mediate cell communication over short distances?
Answer:
The proteins receive electrical signals from nerve cells.
Explanation:
The immune system comprises immune cells that provide defense and protect the body cells and tissues from immunogens.
Immune cells send and receive signals for identifying and attacking pathogens and immunogens.
The cells communicate by:
The proteins interact directly with proteins on the surfaces of other cells.
This can be explained as:
The immune response facilitates the action generally by lymphocytes and T cells.Over short distances, the T-cells and MHC interact with the proteins found on the externals receptors of other cells.The receptors recognize and bind the molecules through the surrounding.Therefore, cells interact directly on protein surfaces.
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"Afrofuturism in entertainment, art, and style does not offer younger generations a mirror where they can see themselves in expansive environments: science, technology, and in social/gender roles."A. TrueB. False
Answer:
False
Explanation:
Since its start in 1993, Afro-futurism offers a wide array of expressions by connecting the the existing traumatic mentality surrounded by astro blackness consciousness to the varied possibilities with in the world. It connect the emerging black identity with the techno cultural advancement around the world imbibing several changing parameters such as digital networks, software platforms, human technologies, algorithms, migration etc. It aims to provide a lens through which black and African culture can see the possible futures and realities.
Hence, the given statement is false
The largest unit within which gene flow can readily occur is a:__________
a) population.
b) species.
c) genus.
d) hybrid.
e) phylum.
Answer:
b) species
Explanation:
A species is a group of individuals that are able to interbreed among themselves. Their progeny is viable and fertile. Since the members of the same species are able to interbreed, gene flow occurs readily between them during the process of sexual reproduction. For example, plants of species Mangifera indica can pollinate each other. When male and female gametes of two plants of Mangifera indica fuse together to form a zygote, genes from these two plants come together in the zygote.
1. Define isometric contraction and describe an example Isometric contraction occurs when the muscle is activated but held at a fixed length. An example would be the muscles of the leg when holding oneself in a squat position.
2. When the current reached the following stages, what proportion of fibers in the muscle were contracting?
a) at threshold
b) at the maximal stimulus
c) above the maximal stimulus
Answer:
1. Isometric contraction is best defined as a contraction that is not associated with any movement. It can be used by the therapist to increase strength and elasticity.
An example of an isometric contraction is carrying an object in front of you. The weight of the object would be pulling downward, but your hands and arms would be opposing the motion with equal force going upwards. Since your arms are neither raising or lowering, your biceps will be isometrically contracting.
2.
a. At threshold just a few muscle fibers are being recruited.
b. At the maximal stimulus is 100% of recruitable fibers are contracting.
c. Above maximal stimulus, the number of contracting fibers cannot increase.
Explanation:
In watermelons, bitter fruit (B) is dominant over sweet fruit (b), and yellow spots (S) are dominant over no spots (s). The genes for the two characteristics assort independently. A homozygous plant that has bitter fruit and yellow spots is crossed with a homozygous plant that has sweet fruit and no spots. The F1are intercrossed to produce the F2.
a) What will the phenotypic ratio be in the F2 generation?
b) If an F1 plant is backcrossed with the bitter, yellow spotted parent what phenotypes and proportions are expected in the offspring?
c) If an F1 plant is backcrossed with the sweet, nonspotted parent what phenotypes and proportions are expected in the offspring?
Answer:
A) 9:3:3:1
B) All bitter fruit, yellow spotted offsprings
C) Phenotypes are bitter yellow spotted (4), bitter no spot (4), sweet yellow spot (4), and sweet no spot (4). 1:1:1:1
Explanation:
This is a typical dihybrid cross involving two genes, one coding for fruit taste and the other for spot color. The allele for bitter taste (B) and yellow spot (S) is dominant over the allele for sweet taste (b) and no spot (s) respectively.
Hence, a heterozygous F1 resulting from a cross between an homozygous dominant (bitter fruit, yellow spot) and homozygous recessive (sweet fruit, no spot) will have a BbSs genotype. The heterozygous F1 offsprings are self-crossed and produce gametes BS, Bs, bS, bs. (See punnet square). The F2 offsprings will have the following phenotypes: Bitter fruit, yellow spot (9)
Bitter fruit, no spot (3)
Sweet fruit, yellow spot (3)
Sweet fruit, no spot (1)
Back cross between a F1 offspring (BbSs) and homozygous dominant parent (BBSS) will produce all bitter fruit, yellow spot offsprings (see attached image). BBSS (4), BBSs (4), BbSS (4), and BbSs (4) are the offsprings' genotypes.
For the back cross between a F1 offspring (BbSs) and a homozygous recessive (bbss) parent, the Phenotypes with their proportions are as follows:
Bitter fruit, yellow spot (BbSs, 4)
Bitter fruit, no spot (Bbss, 4)
Sweet fruit, yellow spot (bbSs, 4)
Sweet fruit, no spot (bbss, 4).
The phenotypic ratio in the F2 generation from crossing two heterozygous watermelon plants (BbSs) is 9:3:3:1. A backcross of an F1 plant with a homozygous bitter, yellow spotted parent results in 100% bitter, spotted offspring. A backcross with a homozygous sweet, non-spotted parent yields a 1:1:1:1 ratio of phenotypes.
Explanation:In classic Mendelian genetics, the cross between a homozygous bitter fruit, yellow-spotted watermelon plant (BBSS) and a homozygous sweet fruit, non-spotted watermelon plant (bbss) results in the F1 generation all being heterozygous (BbSs) since bitter fruit (B) is dominant over sweet fruit (b), and yellow spots (S) are dominant over no spots (s).
Phenotypic Ratio in the F2 Generation
The intercrossing of the F1 generation (BbSs) would result in the F2 generation having a phenotypic ratio of 9:3:3:1. This is because each characteristic (bitter vs sweet and spotted vs non-spotted) is inherited independently, resulting in four possible phenotype combinations: bitter with spots, bitter without spots, sweet with spots, and sweet without spots.
Backcross with Bitter, Yellow Spotted Parent
If an F1 plant (BbSs) is backcrossed with the bitter, yellow spotted parent (BBSS), the expected phenotypes and proportions in the offspring would be all bitter with spots (100% B-S-), due to the dominance of the bitter and spotted traits.
Backcross with Sweet, Nonspotted Parent
Similarly, if an F1 plant (BbSs) is backcrossed with the sweet, non-spotted parent (bbss), the resulting phenotypes and proportions expected in the offspring would be a 1:1:1:1 ratio. This results from the combination of the F1 heterozygous traits with the recessive sweet, non-spotted parent's traits.
_____ includes crude comments or sexual jokes and behaviors that convey hostility toward a particular gender.
Answer:
Gender Harrassment
Explanation:
This could also be called sexism.