Two important reasons are listed here:
- Pre-australopithecines show evidence of bipedalism but they lived in forested areas
- Ardipithecus ramidus is a human ancestor that lived in a wooded environment approximately 4.2 to 4.5 million years ago
The savanna hypothesis states that early hominid traits were selected in response to increased aridity conditions and the emergence of savanna landscapes (i.e., open grasslands), as forests receded. This hypothesis enables us to understand better the evolution of bipedalism.
Pre-Australopithecines represent the oldest hominids that date from at least 7 to 4.4 million years ago (mya), depending on the species. Pre-australopithecines show evidence of bipedalism (and/or dentition similar to the later hominins who exhibit bipedalism), but it has been shown that they lived in forested areas. Therefore, this observation contradicts the savanna hypothesis which states that bipedalism evolved as an adaptation to the savanna.
Ardipithecus ramidus is a human ancestor dating to between 4.5 and 4.2 mya. The Ardipithecus ramidus fossils were discovered in Ethiopia alongside faunal remains, thereby indicating they lived in a wooded environment. In consequence, Ardipithecus ramidus fossils contradict the open savanna explanation for the origin of bipedalism.
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In an experiment to determine the acceleration due to gravity, one student holds a pencil at arm’s length and drops it. Another student starts a timer when the first student lets go and stops the timer when the pencil hits the ground. They repeat this several times and take an average. Is this a valid experiment, why or why not?
Answer:
The correct answer is - No, it is not valid because the short distance means there will be a lot of error due to the student's reaction time.
Explanation:
In this experiment to determine the acceleration due to gravity, there may be errors because of the student’s reaction time. The reaction can be late or early than prior reactions.
The other error can be caused by the distance was only at arm’s length throughout the experiment, which means that there was no independent variable that is the difference or change in the distance. This also makes the experiment invalid.
Explain why the lack of surfactant would result in respiratory distress. Furthermore, what type of acid-base disorder might she develop and how would her body compensate. Be detailed in your explanation and support your answer with facts from your textbook, research, and articles from scholarly journals.
Answer:
Due to lack of expansion of lungs.
Explanation:
The lack of surfactant compound would result in respiratory distress because Surfactant enables the lungs to expand more easily which allows easiness in respiration. Without surfactant, the air sacs in the lungs will collapse very easily. This collapse leads to decreased amounts of air or oxygen in the lungs which makes it very difficult for the people or infant to breathe.
why does a rational producer reject the business in increasing stage
Answer:
In three stages of production to which are hold by the law of diminishing marginal returns the second stage is considered to as the rational stage of production as compared to the first and third stage this is due to the fact that this stage it comes out with the best assumptions for efficient and sustainable production, thereby the stage it simultaneously shows the positivity of the average products and marginal product hence, in the increase of labour the total production or outputs increased likewise with the same quantity of fixed factor, therefore this stage it gives direction to the producer on how the higher units of output can be produced.
Unlike the first stage to which it shows each additional variable could enhance more production and such this it signifies an increasing of marginal return but for this case it do not give out the direction in permanent production since labours are needed fewer and in the decrease in number of labour can brings about underproduction.
Also the third stage marginal return is frankly negative because in adding more variable inputs will further led into adding more number of labour hence the increase of labour will contributes to under production as it may be due to labour capacity and efficiency concern.
If you measured the energy content of organisms in each trophic level in an ecosystem, which would have the greatest total energy content
A forest was cleared and turned into a field of organic soybean plants. Which of the following most likely occurred?
A. The variety of plants and animals both increased
B. The number of insects increased
C. The number of insects decreased
D. The number of plant species increased
When a forest is cleared, biodiversity decreases. The correct answer is option C: The number of insects decreased
Biodiversity refers to different species of plants and animals in a habitat. We will all agree that the biodiversity in a forest ecosystem is much higher than the biodiversity in a field of organic soybean plants.
There are less species of organisms in the field of organic soybean plants.
Therefore, the variety of plants and animals both decrease.
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The MN blood group in humans is under the control of a pair of co-dominant alleles, M (we will call the frequency of M, p) and N (we will call the frequency of N, q). In a group of 556 individuals, the following numbers of individuals are found for each of the genotypes:
167 MM
280 MN
109 NN
a) What is the frequency of each allele? p= q=
b) What is the value of the Chi-square statistic test to find if in this particular case the genotypic frequencies conform to the Hardy-Weinberg distribution.
Chi square value =
c) What is the probability associated with you chi square statistic calculated above? Please complete the blanks below with the corresponding symbol, < OR > than the critical value, your conclusion with respect to the null hypothesis of Hardy Weinberg equilibrium, Retain or Reject.
P value __ than 0.05
Conclusion ___ the null hypothesis of HW equilibrium
Answer:
a) f(M) = p = 0.55
f(N) = q = 0.45
b) X² = 12.12
c) P₀.₀₅ = 5.991
d) P₀.₀₅ < X²
e) Reject the null hypothesis of HW equilibrium
Explanation:
Due to technical problems, you will find the complete explanation in the attached files
Which energy containing molecule is readily used around the cell to power its processes?
A. Glucose
B. ATP
C. ADP
D. Lipids
Answer:
Adenosine 5'-triphosphate, or ATP, is the most abundant energy carrier molecule in cells
ATP is an energy-containing molecule that is readily used around the cell to power its processes. Thus, the correct option is B.
What is ATP?ATP stands for Adenosine triphosphate. ATP may be defined as an organic compound that is utilized as the source of energy for use and storage at the cellular level.
It is the molecule that is present in the cells of all living entities to carry out specific metabolic activities. It apprehends chemical energy aquire from the breakdown of food and liberation it to fuel other cellular processes.
Therefore, ATP is an energy-containing molecule that is readily used around the cell to power its processes. Thus, the correct option is B.
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Muscle cells that are worked often in exercise will require more mitochondria. If we use more mitochondria, it will require us to use more carbohydrates to build ATP’s. What if we run out of carbohydrates stored in our body? What macromolecule can we break down and use in cellular respiration?
Group of answer choices
A) sucrose
B) lactose
C) glycogen
D) lipids
Answer:
Lipids
Explanation:
For both clinical and cosmetic reasons, plastic surgeons inject substances into connective tissue underlying the skin epidermis. This plumps up areas deficient in soft tissue, and is used to reduce surgical scars or wrinkles, for example. Which normal connective tissue components are good candidates to be injected as fillers in this type of procedure
Answer:B.) collagen
C.) glycosaminoglycan
Explanation:
What do you understand by each of the following terms
a.DNA nucleotide
b.RNA nucleotide
The locus B on the X chromosome of a malaria-carrying mosquito shows a 49% recombination rate with respect to the locus M. Since a recombination rate of 50% is essentially indistinguishable from independent assortment, you might be tempted to look for a locus that falls between B and M. Before you decide to do all that work, you run a chi square test to determine the P value of your experiment.
Required:
What range of P values would tell you that you should accept the conclusion that locus B and locus M are, indeed, 49mu apart and that another locus is not necessary?
Answer:
The correct answer is - P = 0.45
Explanation:
The Chi-square test is a test that determines the assorted genes independently. Here p-values used to make conclusions in significance testing.
If the p value is less than the significance level we expect or choose, then this null hypothesis is rejected in favor of the alternative hypothesis. It p value is greater than or equal to the significance level, then we fail to reject the null hypothesis.
So in this case, as the recombination rate is 49% so the p value which satisfies the conclusion will be around 0.45 and values near to it.
In the test tube channel below what is produced by the snail that is used by the plant?
If you have genotypes TTHh and ttHH, what is the probability of getting an offspring that is TtHH?
Answer:
50% or 1/2 in fraction form
Different measures of disease are useful to evaluate and assess public health programs and needs in different situations. For each of the following questions, state which measure would best support your goal.
Measures of disease:
I = incidence rate (p. 126)
P = prevalence (p. 113)
L = lifetime prevalence (p. 114)
M = crude mortality rate (crude death rate) (p. 112)
R = sex ratio (counts) (p. 109)
a. To demonstrate the risks of car-train crashes at railroad crossings without warning signals.
b. To demonstrate the amount of children's exposure to secondhand cigarette smoke.
c. To estimate the number of persons who have had leukemia during their lifetimes.
d. To estimate the number of healthcare facilities needed to support patients with Alzheimer's disease.
e. To argue that mortality from HIV infection is a more serious public health problem in one region of the US than another.
Answer:
Different Measures of Disease
Question Measure of Disease
a. I = incidence rate
b. P = prevalence
c. L = lifetime prevalence
d. L = lifetime prevalence
e. M = crude mortality rate
Explanation:
a) Measures of disease:
I = incidence rate (p. 126): measures the frequency of disease occurrence in a population over time. It is measured as new episodes of illness in a period divided by the population.
P = prevalence (p. 113): ratio or proportion of persons in a population with a disease at a time or over time. It is based on a sample.
L = lifetime prevalence (p. 114): the proportion or ratio of a population who had a disease at some point in their life.
M = crude mortality rate (crude death rate) (p. 112): the ratio of deaths in a period among a geographical population.
R = sex ratio (counts) (p. 109): ratio of male and female population.
Name one component of the digestive system that performs mechanical digestion and describe how
it contributes to acquiring nutrients from food.
Answer:
The stomach and the teeth both perform mechanical digestion, which is physically (as opposed to chemically) breaking the food into smaller components. This exposes a larger surface area for chemical digestion and release of nutrients. The teeth are vital to mastication, which breaks large bites of food down into smaller pieces that are easily swallowed. The stomach’s muscle contractions churn the food to expose all particles to the acid and digestive enzymes..
The following types of tissue all are part of the category named muscle tissue:
Skeletal muscle
Smooth muscle
Cardiac muscle
3
Visceral muscle
A. B. and Care all correct.
Answer:
A, B and C are all correct.
Explanation:
There are three main muscle types:
Muscle skeleton — the specialized tissue that connects to the bones and enables movement. The musculoskeletal system is called skeleton muscles and bones together (also known as the locomotor system). Generally speaking, the biceps and triceps of the front or the back of the upper arm are arranged into opposing pairs. Skeletal muscles are controlled by humans, and so are also called voluntary muscles. Another term is streaked muscles, as the tissue looks streaked on a microscope. smooth muscle -located throughout several internal tissues such as the digestive tract, the uterus, and blood vessels such as the artery. The smooth muscle in layered sheets is placed along the construction length in waves. Another typical word is an involuntary muscle, because, without our knowledge, the motion of the smooth muscle takes place.The cardiac muscle - the heart muscle. Without our conscious awareness the heart contracts and relaxes.DNA is referred to as a_____,
meaning that it has_______
strands that are______together.
Answer:
double helix
two
wound
Explanation:
DNA is referred to as double helix, meaning it has two strands that are wound together.
Suppose that you close a window because you notice that rain is falling. Your action in closing the window is a(n)
A. involuntary reaction.
B. depressant.
C. stimulus.
D. response.
Answer:
D. Response
Explanation:
Basically, You Are Coordinating What Is Happening Which Triggers The Brain For A Response.
Answer:
D.
Explanation:
You are responding to the rain by closing the window.
- it is not an involuntary action because that is something that doesn't require thinking such as breathing and blinking.
- it is not a depressant because that is something that reduces functional activity - so affects the body.
- it is not a stimulus because a stimulus is a change or signal in the environment that can make an organism react. So, in this case the rain would be the stimulus.
Hypoxia is known to cause a disruption of somitogenesis. If a mouse embryo were temporarily exposed to low levels of oxygen during the final stages of somitogenesis, what would you expect to see in the vertebral column of the newborn mouse
In mammals, hypoxia may cause defects during fetal development. In this case, it would be expected to observe an abnormal development of the caudal (tail) vertebrae
Somitogenesis refers to the process during embryo development in which somites form. These somites are cells that will give rise to structures associated with the vertebrae body plan. Somites form sequentially from the head to the tail, where each new somite forms on the caudal or tail region of the previous one.Somitogenesis represents the first sign of segmentation of the developing vertebrate embryo. During somitogenesis, the unsegmented paraxial or presomitic mesoderm in the trilaminar embryonic stage is segmented in order to form pairs of somites. Moreover, caudal vertebrae refer to the bones that form the tail of vertebrates, which derive from caudal somites.Embryo hypoxia refers to the condition in which the developing embryo does not receive sufficient oxygen (O2) supply. It has been shown that hypoxia during embryo development can increase the incidence of malformations. In this case, embryo hypoxia affects normal caudal somite segmentation, thereby leading to defects in the caudal (tail) vertebrae.Learn more about this topic here:
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The development of DNA technology is bringing profound changes to science, agriculture and healthcare. Provide one example of a DNA technology and provide at least one advantage and one example of a concern or problem associated with its use.
Answer:
The CRISPR-Cas9 genome editing system can be used to edit genes and correct mutations associated with inherited diseases. However, this technology also has the potential to edit genes in germline cells in order to irreversibly modify the human species and the natural evolution of life
Explanation:
The CRISPR-Cas9 (Clustered regularly interspaced short palindromic repeats and CRISPR-associated protein 9) system is a natural prokaryotic defense system used by bacteria to defend against invading DNA. In the laboratory, the CRISPR-Cas9 system has been repurposed to create a versatile genome-editing tool that allows us to modify the genome of mammalian cells in a targeted fashion. The CRISPR-Cas9 is a simple gene-editing tool that consists of a single guide RNA (sgRNA) that guides the Cas9 enzyme to the exact genomic location where Cas9 needs to make a cut, which is then repaired by different DNA repair mechanisms. During DNA repair, nucleotides can be replaced and/or deleted, thereby producing desired genomic modifications. The CRISPR-Cas9 has an enormous potential to repair mutations in genes associated with inherited genetic disorders and cancer (i.e., oncogenes might be reversed in vivo by using this technology). However, the CRISPR-Cas9 genome editing system is also a subject of concern due to its dual use. For example, this technology can be used to modify the genome of germline cells by inducing mutations that can be passed across generations, thereby irreversibly modifying human DNA and altering the normal course of evolution.
In another experiment, the leu gene was found to be located 5 minutes from the pro gene. In which location(s) in the gene map could the leu gene be located? (Note that the distances depicted between the genes on the map are not to scale.)
Answer: Hello your question has some missing data attached below is the missing data
answer:
positions : A and E
Explanation:
Given that the leu gene was found 5 minutes from pro⁺ gene hence it can be located either after the bio⁺ gene or before met⁺ genes
hence the locations in the gene map = A and E
attached below is the transfer of genes
what is the effect of increasing the concentration of each of the following metabolites on the net rate of glycolysis; 1.glucose 6-phosphate. 2. Fructose 1,6-bisphosphate 3. citrate 4. Fructose 2,6-bisphosphate
Answer:
hlo everyone how are you all ☆☆☆
Which of the following statements is false? Choose one: A. Some Bcl2 family members promote apoptosis, whereas others inhibit apoptosis. B. Bax and Bak are death-promoting members of the Bcl2 family that induce the release of cytochrome c from mitochondria into the cytosol. C. Some death-inhibiting members of the Bcl2 family inhibit apoptosis by blocking cytochrome c release from mitochondria. D. The death-promoting members of the Bcl2 family include Bcl2 itself.
Answer: The statement that is FALSE is D (The death-promoting members of the Bcl2 family include Bcl2 itself.)
Explanation:
Apoptosis is a process found in multicellular organisms whereby cells follows a order of events which eventually leads to their death without releasing harmful substances into the surrounding area of the cells. Through this process, old cells, unnecessary cells, and unhealthy cells are eliminated from the body.
The process of apoptosis can be regulated by cell regulator proteins such as Bcl-2 family.
Bcl-2 stands for B-cell lymphoma 2 which are encoded in human cells by BCL2 gene. The Bcl-2 family are capable of regulating apoptosis by either inducing it or inhibiting it.
Bcl-2 and Bcl-XL, PREVENT apoptosis by preventing the release of mitochondrial apoptogenic factors such as cytochrome c and AIF (apoptosis-inducing factor) into the cytoplasm
Part of the Bcl-2 family is the Bax and Bak and they are the core regulators of the intrinsic pathway of apoptosis. They PROMOTE apoptosis by inducing the release of cytochrome c from mitochondria into the cytosol. Therefore, the death-promoting members of the Bcl2 family does not include Bcl2 itself.
The fact that only your liver cells produce liver enzyme and not your skin cells, which contain the same DNA, can be explained by O PCR O gene expression O gene flow NA
Answer:
Gene expression
Explanation:
Gene expression is the process in which cells (usually eukaryotic) have niches , meaning that one set of genes is expressed in once cell and different ones in another
help me in my hw landslide can be prevented by terrace farming why
Answer:
Reducing the intensity of runoff.
Explanation:
Terrace farming prevent landslides and erosion to occur by reducing the intensity of runoff. This farming also reduce the risk of drought due to raising the moisture content in the soil and allowing water to slowly infiltrate into the soil. Due to terrace farming, the runoff water moves very slowly which causes less erosion of the soil as well as reduces the intensity of water flow which causes more infiltration.
You are studying an enzyme that is inactivated by phosphorylation and create a mutant in which the threonine that is normally phosphorylated is replaced with glutamate. Predict the impact of this change on the activity of this enzyme. Group of answer choices
Answer:
always active
Explanation:
Phosphorylation is a posttranslational modification that consists of the addition of phosphate groups to specific amino acids on the protein. Phosphorylation acts as a molecular switch for proteins that are phosphorylated (i.e., in some situations phosphorylation acts to activate protein function, whereas in other situations phosphorylation can inactivate protein function). Phosphorylation modifies the three-dimensional structure of the protein, thereby affecting, for example, the accessibility of the active site of a phosphorylated enzyme to its substrate. Phosphorylation can occur only at the side chains of three amino acids: Serine, Threonine and Tyrosine. In this case, the enzyme is inactivated by phosphorylation on the Threonine residue, so it is expected that the mutant enzyme cannot be phosphorylated, remaining in an active state.
A geneticist finds that a strain of bacteria to produces a non-functional sigma factor. Which among the following steps in transcription would most likely be first affected?
A.Assembly of RNAP onto the DNA strand
B.Identification and binding of RNAP on to the promoter sequence
C.Conversion of open initiation complex to closed initiation complex
D.Synthesis of RNA after the formation of open initiation complex
Answer:
The correct answer is - B. Identification and binding of RNAP onto the promoter sequence.
Explanation:
Bacterial RNA polymerases have subunits known as Sigma factors responsible for the identification and specificity of promoter binding of RNAP and regulate the efficiency of RNA synthesis during transcription is initiated.
These bacteria producing the nonfunctional subunits of RNA polymerase or sigma factor will be unable to identify and tightly bind to promoter elements that are RNAP.
All of the members of a particular species that live in one area are called a(an):
A) biotope
B) community
C) ecosystem
D) biosphere
E) population
Answer:
Population
Explanation:
population- all the members of one species in a particular area.
In the oceans on either side of the Isthmus of Panama are 30 species of snapping shrimp, 15 species on the Pacific side and 15 different species on the Atlantic side. Species live at different water depths. Morphological and genetic data show that Atlantic and Pacific species that live at similar depths are sister species. The sister species on each side of the isthmus cannot interbreed because the water in the canal is fresh water, not salt water, and provides a barrier to reproduction. A sea-level, salt-water canal between the two oceans has been proposed to make transport across the isthmus easier. Which of the following outcomes is the most likely result if such a canal were built?
A. greater percentage of difference in DNA sequences between sister species that inhabit deep water than between sister species that inhabt stalow water
B. greater percentage of difference in DNA sequences between sister species that inhabit shallow water than between sister species that inhabit deep water
C. similar percentages of difference in DNA sequences between all pairs of sister species
D. greater percentage of difference in DNA sequences between Atlantic species than between Pacific species
Answer:
The options of this question are wrong, you can find the correct options by navigating on the web. The options of this question are as follow:
1) The sister species will continue to diverge from each other.
2) None of the sister species will interbreed with each other.
3) The Atlantic and Pacific shrimp will continue to live in their respective oceans and not enter the new canal.
4) Shallow-water species from the two oceans that are sister species would be more likely to interbreed with each other than would be deep-water species.
Answer:
4) Shallow-water species from the two oceans that are sister species would be more likely to interbreed with each other than would be deep-water species
Explanation:
In evolutionary biology, sister species are defined as descendant species formed when one species splits during the course of evolution. Moreover, adaptation refers to the evolutionary process of adjustment of organisms to the environment, which is usually due to natural selection. During the course of evolution, organisms under different environments must change to adapt to their environments. In this case, it is expected that sister species that live in similar environmental conditions (i.e., shallow-water species) exhibit fewer phenotypic differences, being therefore more likely to interbreed with each other.
Unlike skeletal muscle, the muscle cells of the heart (called "cardiomyocytes") metabolize very little glucose, relying almost exclusively on metabolism of fatty acids for their energy. Which of the following statements are likely to be true of cardiomyocytes, but NOT skeletal myocytes? (select two answers)
a. low levels of glycogen storage, even when blood glucose is high
b. high levels of glycogen storage, even when blood glucose is low
c. low lactate production, even at high activity
d. high lactate production, even at low activity
e. many mitochondria compared to other cells
f. few mitochondria compared to other cells
Answer: A. low levels of glycogen storage, even when blood glucose is high.
C. low lactate production, even at high activity.
Explanation:
Cardiomyocytes are also known as the myocardiocytes. They are the cells which makes up make up the muscle if the heart. They're responsible for the generation of the contractile force in the heart which helps in the pumping if blood.
From the options given, the statements that are likely to be true of cardiomyocytes, but not of skeletal myocytes include:
• low levels of glycogen storage, even when blood glucose is high.
• low lactate production, even at high activity.
Answer:
The answer is A and C
Explanation:
Since cardiomyocytes are dependent on fatty acids, they rely on oxidative phosphorylation to generate energy, and consume very little glucose. Due to this, they have very low need for fermentation of pyruvate. In fact, they can absorb lactate generated by skeletal myocytes and erythrocytes and oxidize it for additional energy. Another consequence of this metabolism is that cardiomyocytes store little or no glucose as glycogen.
Skeletal myocytes and cardiomyocytes both have high energy needs and thus have more mitochondria than other cells. Cardiomyocytes have an even greater density of mitochondria than skeletal myocytes because they depend almost entirely on oxidative phosphorylation for their energy needs. This dependence on oxidative phosphorylation also explains the extraordinary sensitivity of cardiac muscle to hypoxic (low-oxygen) events. Without oxygen, cardiomyocytes rapidly run out of energy and can quickly die.
