Would you expect a shrub or dandelion (dispersed by wind-blown seed) to be a more likely pioneer plant species? why? Thank you so much for helping! means a lot !

Answer:

Option (b).

Explanation:

Breathing may be defined as the inhalation of oxygen and exhalation of carbon dioxide. The breathing depends on the various internal and external factors.

The partial pressure of oxygen is directly proportional to the breathing and the inhalation of oxygen in the body. The altitude contains lower atmospheric pressure and the partial pressure o the oxygen decreases at high altitude. The decrease in the partial pressure of the oxygen reduces the affinity of oxygen with hemoglobin and thus an individual feels difficulty in breathing.

Thus, the correct answer is option (b).

Answer:

True

Explanation:

The plasma half-life of a hormone is inversely related to its metabolic clearance rate (MCR) is true Statement.

Half life of a hormones is the life after which a hormone looses its half of pharmacological and physiological life whereas metabolic clearance rate is the volume of biological units cleared completely of drug metabolites as measured in unit time.

Answer:

Water soluble hormone binds to the membrane bound receptors whereas lipid soluble hormones bind to the internal/intracellular receptors.

Explanation:

Hormones are called regulators because they can either stimulate or inhibit the target cell's activity.

They perform their action by binding to specific protein on target tissue called hormone receptors. Each receptor is specific for a particular hormone. The hormone-receptor complex bring about the biochemical changes in the target cell.

Hydrophillic or water soluble hormones interact with the membrane bound receptors. They result in the generation of secondary messengers such as cyclic AMP. Secondary messengers bring about the cascading action amplifying the final effect. That is why even a very small quantity of hormone is sufficient for a powerful cascading effect.

Lipid soluble hormones can diffuse through the plasma membrane and thus  they bind to the intracellular receptors. The hormone-internal receptor complex enters the mucleus and regulates gene expression. Example: steroid hormones and thyroid hormones.

Lipid-soluble hormones can cross the cell membrane and directly influence gene expression, while water-soluble hormones bind to receptors on the cell membrane and trigger intracellular signaling pathways.

Lipid-soluble hormones, such as steroid hormones, can pass through the cell membrane and bind to receptors in the cytoplasm or nucleus of target cells. Once inside the cell, they directly influence gene expression and protein synthesis, leading to changes in cell function.

Water-soluble hormones, such as peptide hormones, cannot pass through the cell membrane. Instead, they bind to receptors on the cell membrane surface and trigger intracellular signaling pathways, which ultimately result in the desired cellular response.

Overall, the main difference between lipid-soluble and water-soluble hormones is their ability to cross the cell membrane and where their receptors are located.

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The closest relatives of fungi are thought to be the ANIMALS (Option A).

In recent years, it has been estimated that ancestral fungi split from animals approximately 1.540 billion years ago.

Moreover, ancestral plants split from animals approximately 1.550 billion years ago.

In consequence, it has been proposed that fungi are more closely related to animals than to plants (i.e., fungi and animals share a more recent common ancestor with each other than with plants).

In conclusion, the closest relatives of fungi are thought to be the ANIMALS (Option A).

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Fungi are most closely related to animals based on recent DNA evidence. They share a common ancestor, causing them to have several similarities such as their mode of nutrition and cell structure.

The closest relatives of fungi are believed to be the animals. This is based on recent DNA evidence which suggests that fungi and animals share a common ancestor and thus, are more closely related to each other than they are to plants or other organisms. Essentially, Fungi and animals fall under the same supergroup, known as Opisthokonta. Fungi and animals have several similarities including their mode of nutrition and the structure of their cells.

While fungi were often categorized as plants in the past, they share more similar characteristics with animals, such as the storage of carbohydrates as glycogen (like in animals) instead of starch (like in plants). Therefore, choice a. animals would be the most accurate answer.

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Answer:

the need for a steady supply of low-cost labor increased

Explanation:

In the beginning (18th century) before slavery, indentured servitude was a way for poor Euopeans to pay their way for the costly voyage across the Atlantic to the New Colonies.  Their contract terms were fixed in which they worked for their landowners or shippers until their debt was paid. As more and more of these indentured servitude served their contracts and became free, they also increased the demand for labor as they became landowners. The need for labor increased and the cost of indentured servants also increased.

White landowners, especially in early Virginia, turned to Africa for servitude. With time, using race to undermine Africans, greed for profits by landowners resulted in slavery and enactment of Slave Law in 1641.

Slavery began to replace indentured servitude due to the need for a consistent, cheap labor force in the American colonies. The arrival of Africans and the demands for freedom dues by indentured servants added challenges, leading to colonists to shift towards slavery.

The system of slavery began to replace indentured servitude primarily due to socioeconomic reasons during the colonial period. Indentured servitude often led to social mobility and advancement once a servant's contract had ended, which created an inconsistent labor source for colonists. Colonists required a consistent, cheap workforce to cultivate profitable cash crops such as tobacco and cotton.

The arrival of Africans provided a new source of cheap labor. By classifying these individuals as property, colonists created an unchanging workforce. In addition to this, the demand for “freedom dues” from former indentured servants was hard to maintain. Furthermore, the economic need for a steady supply of low-cost labor due to the expanding plantation economy was a driving factor.

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Answer:

Darwin gave the concept in evolution of species.

Explanation:

Answer:

cretaceous period

Explanation:

the abiogenesis started in -4100  millions years ago.

source: curtis. biology 8th edition.

The life began during the time of Paleozoic Era.

The Phanerozoic Eon is classified as three era namely:

The initiation of life was seen during Paleozoic era. It began 542 million years back with the development of complex living things and finished 251 million years prior with the biggest mass elimination the world has ever experienced. It is the most seasoned and longest period of Phanerozoic Eon.

Answer:a. humans and chimpanzees share a relatively recent common ancestor.

Explanation:

Humans and chimpanzees are not evolved from one another, but both have a common ancestors. Humans share a common ape ancestor with chimpanzees who is expected to live 6-8 million years ago. The humans and chimpanzees have been evolved differently from this ancestor.

The most likely explanation for this result is that humans and chimpanzees share a relatively recent common ancestor.

Scientists tend to believe that our common ancestor with the chimpanzee lived between 9 and 7 million years ago. Sahelantropus tchadensis is the closest hominin to this date that we know of.

With this information, we can conclude that the most likely explanation for this result is that humans and chimpanzees share a relatively recent common ancestor.

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Answer:

Explanation:

From Mendel’s Law of Segregation we can expect, as a result of a monohybrid cross, a phenotypic ratio of 3:1 in the offspring.

If you get a different ratio such as 2:1, and notice that a particular genotype does not appear in the offspring, you can suspect that genotype is lethal.

Mendel’s Law of Independent Assortment on the other hand says that the offspring resulting from a dihybrid cross will have a phenotypic ratio of 9:3:3:1.

If you get numbers that don't match the expected ratios, and are smaller numbers like 4:2:2:1, and notice that a particular combination of alleles does not appear, you can suspect that allele is recessive and lethal in an homozygous individual.

Answer:

b. Red blood cells that lack nuclei

d. A fully erect posture associated with bipedalism

Explanation:

Eccrine glands can be found on horses, you may have seen horses sweeting. The pressure sensors can be found in other apes too. Fully erect posture is a characteristic of humans, other apes or monkeys may walk sometime like this, but their main locomotion is in 4 extremities. Non nucleated is a characteristic that gives an advantage because more oxygen can be carried  inside red blood cells making respiration more efficient.

Answer:

The organisms use DNA as the genetic (contains code of life) as well as heredity (transferred to progeny) material.

DNA is packaged into a highly condensed structure called chromosome which gets passed on to progeny through male and female gametes. The formation of the gametes involves meiosis which introduces recombination of the sequence of the DNA.  

The chromosomes contain a sequence of DNA called genes which codes for a particular trait of organisms. These genes control a trait when they receive the complementary form of the gene from another chromosome.  

When the gametes fuse then both the gametes contribute half of their chromosomes and make a complete set of chromosomes. Thus, the continuity of life is controlled by heredity material.

Continuity of life is ensured by parents passing genes, in the form of alleles, to their OFfspring. This process, driven by meiosis, ensures both perpetuation and genetic variation in offspring. This variation allows traits to evolve over time while maintaining species continuity.

Continuity of life is fundamentally driven by the heritable transmission of DNA from parents to offspring. Parents pass on genes, which are organized in DNA and carry information specifying particular traits. The specific form of a gene, termed an allele, can result in differing forms of a trait. A parent with two different alleles for a trait can pass either allele to their offspring, ensuring both perpetuation of their traits and genetic variation.

During reproduction, a process called meiosis takes place in which parent cells divide to create sex cells, each containing a unique combination of alleles. This creates genetic variance and providing the raw material for evolution. Offspring receiving different combinations of alleles express traits that may appear to be a blend of parental traits, explaining how genetic material is passed down while still creating unique individuals.

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Answer:

a) The correct answer is 1/2 or 0.5

Cystic fibrosis is a recessive disorder and her sibling has a disease but none of the parents had it. Thus, each of the parents must be the carrier of the disease, that is, both of them must be heterzygous.

So, if we cross Cc x Cc, it results in the genotype ratio of 1 (CC) : 2 (Cc) : 1 (cc)

Thus, 2 out of 4 would be the carrier of the disease.

b) 1/16

The probability of female to the carrier is 1/2

Same is the case with male partner due to the probability that he would be the carrier is 1/2

If both are carrier then, there is only 1/4 chances that the offspring will have the disease (as per cross shown above).

Now, the probability that the offspring will have the disease = product of all the above probabilities. (The probability of occurrence of two independent events is equal to the product of their individual probabilities).

So, [tex]\frac{1}{2}x\frac{1}{2}x\frac{1}{4}[/tex] = [tex]\frac{1}{16}[/tex]

c) 1/8

The probability of female to be the carrier is 1/2

The probability male to be the carrier is 1/2

If both are carrier then, there is only 2/4 chances that the offspring will be the carrier of the disease (as per cross shown above).

Now, the probability that the offspring will be the carrier = product of all the above probabilities. (The probability of occurrence of two independent events is equal to the product of their individual probabilities).

[tex]\frac{1}{2}x\frac{1}{2}x\frac{2}{4}[/tex] = [tex]\frac{1}{8}[/tex]

Cystic fibrosis is a recessive disease requiring two copies of the mutant gene. The female in the couple is guaranteed to be a carrier since both her siblings are affected. The chances of their child having cystic fibrosis is 25%, while the chances of the child being a carrier is 50%.

Cystic fibrosis is a recessive disease that requires an individual to inherit two copies of the mutant gene in order to develop the disease. In this case, both members of the young couple have siblings affected with cystic fibrosis, indicating that they are carriers of the mutant gene.

a. The probability that the female of this couple is a carrier is 100%, as both her siblings are affected with cystic fibrosis.

b. The chances that their child will be affected with cystic fibrosis is 25%, as shown by the Punnett square.

c. The probability that their child will be a carrier of the cystic fibrosis mutation is 50%, as 50% of the normal children will carry the gene without any symptoms of the disease.

Answer:

Family: Paramyxoviridae

Genus:  Rubulavirus

Explanation:

Mumps virus is a member of family Paramyxoviridae, subfamily Paramyxovirinae, and the genus Rubulavirus.

The family Paramyxoviridae includes single-stranded RNA viruses with helical symmetry of capsid. These are enveloped viruses and mostly affect the animals as their host.

The Rubulavirus uses the gastrointestinal tract to enter the host and has an incubation period of 2-3 weeks. These viruses are characterized by the formation of large multinucleated cells called syncytium during infection.

Answer:

Explanation:

Cell specialization is also called cell differentiation. Through this process, specialized cells form from the unspecialized cells. Then many cells are formed and determined to form specialized functions.

The stem cells are the unspecialized cells which form a different kind of specialized cells.  

The muscle cells, nerve cells, sperm cells, red blood cells are specialized cells perform different specialized functions. All these cells arise from stem cells. The nerve cells receive impulse, muscle cells can contract, etc.

There are certain inductive signaling genes that send the signal to the differentiated cells. These signaling molecules are called ligands. These ligands move to another cell to produce specialized cells. In other words, there are some transcription factors and genes responsible for such cell differentiation and the formation of specialized cells.

Another example is zygote, which is an unspecialized cell. This is also a totipotent cell that has the potentiality to reproduce different cells.

Answer:

Watson & Crick

Explanation:

DNA is present as the genetic material of all the living organism. The DNA contains of the nitrogenous bases, pentose sugar and the phosphate group.  

The X ray structure of the DNA was given by Franklin. The structure of the DNA molecule and its properties was fully explained by the Watson and crick. They explains the polarity, base pairing and the arrangement of the DNA structure.

Thus, the correct answer is option (d).

James Watson and Francis Crick discovered the structure of the DNA molecule in 1953. They proposed the double helix model of DNA, which has proven to be crucial in the field of genetic engineering. The correct answer to the student's question is 'd. Watson & Crick'.

The DNA molecule was discovered byJames Watson and Francis Crick.

In 1953, they proposed the double helix model of DNA. Their discovery was extremely important because it showed how genetic information is passed from one generation to another. This laid the groundwork for a whole new area of scientific research known as genetic engineering.

The answer to the question is: d. Watson & Crick.

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Answer:

Barr body may be defined as the one of the inactive X chromsome of the human female. The human female consists of XX chromosome whereas XY in male. To compensate the extra X chromosome in female one of the X chromosome become inactive and known as barr body. The barr body is found in the somatic  cells.

Lyon hypothesis:

Lyon hypothesis states that dosage compensation occur in human females by the random inactivation of one of the X chromosome. The inactivated X chromosome is named as barr body. The lyon hypothesis was given by Mary Lyon.

Answer:

(a) 16 % of the alien genome is comprised of G.

(b) 17% of the alien genome is comprised of T.

(c) 17% of the alien genome is comprised of A.

(d) 22 % of the alien genome is comprised of X.

Explanation:

Assuming the alien follows Chargaff's rules which states that DNA from any cell of any organisms should have a 1:1 ratio (base Pair Rule) of pyrimidine and purine bases.

So if:

16% contains C ; 16 % pairs with G = 32% C-G pairing.

22% contains Y ; 22 % pairs with X = 44% X-Y pairing.

44% G-C + 32% X-Y =  76%

100%-76% = 34% the remaining should be split between T and A which is 17% each one.

Using Chargaff's Rule, 16% of the alien genome is comprised of G, and 22% is comprised of T. Percentages for A and X cannot be determined without additional information.

Given that 16% of the alien genome is comprised of nucleotides containing C, and 22% is comprised of nucleotides containing Y, we can calculate the percentages of the remaining nucleotides by applying Chargaff's Rule, which states that DNA is a double helix that is held together by base pairs: A pairs with T, and G pairs with C. This means that the percentage of nucleotides containing G will be equal to that of C, and T will complement Y assuming that Y pairs with T in this alien genome, as A pairs with T in Earth organisms.

(a) Since 16% of the alien genome is comprised of C, then 16% of the alien genome is also comprised of G, as G pairs with C.

(b) If 22% is comprised of Y, and assuming Y pairs with T, then 22% of the alien genome is comprised of T.

(c) To find the percentage of A, we would need additional information since the question doesn't provide a direct pairing percentage. Given no other information, the percentage of A remains undetermined in this hypothetical situation.

(d) Without additional information about what X pairs with, we cannot accurately determine the percentage of X in the alien genome. If X pairs with an unknown or non-standard base or does not directly pair with one of the given nucleotides, we would not be able to apply Chargaff's Rule.

The correct answer is D. According to DNA comparisons, humans share a common ancestor with chimpanzees.

Explanation

A scientific statement is a statement made based on scientific evidence, that is, a scientific statement is the result of several tests focused on testing a hypothesis or proposal. These scientific statements can be developed in different areas of knowledge such as science, biology, physics, mathematics, geometry, among others. they are also predominant in the exact sciences because in the human sciences it is complicated to establish scientific statements because human behavior does not obey exact laws. According to this definition, option D. is the correct answer because it refers to DNA tests between humans and chimpanzees and therefore this is based on scientific evidence and tests.

DNA replication contributes to heredity only, while crossing over, the alignment and separation of chromosomes in metaphase and anaphase I and II, and fertilization contribute to both heredity and genetic variation. These processes ensure a complete set of genes is inherited while also introducing genetic diversity.

The process of heredity and genetic variation are guaranteed through DNA replication, crossing over, and the stages of meiosis including metaphase to anaphase I and II and the process of fertilization. In terms of DNA replication (assuming no errors), this contributes to heredity only as it enables a complete set of chromosomes to be passed down from the parent to the offspring. Crossing over, or the process of chromosomes exchanging segments during meiosis, contributes to both heredity and genetic variation as it ensures genes are transmitted and also adds variation through the reshuffling. The alignment of chromosomes in metaphase I and II and their separation in anaphase I and II contributes to both heredity and genetic variation as these stages ensure accurate division and distribution of genetic material and add variation through independent assortment. Lastly, fertilization, the process in which the egg and sperm unite their genetic material also contributes to both heredity and genetic variation, ensuring offspring inherits a complete set of genes from each parent and introducing variation through the random selection of each parent's genes.

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Answer:

b. mRNA from DNA

Explanation:

Transcription is the process of synthesis of RNA using a DNA template strand. The process of transcription occurs inside the nucleus in eukaryotes as their DNA is present in the nucleus.

The process includes unwinding of DNA double helix to expose the DNA template strand. The enzyme RNA polymerase binds to the specific start sites on the DNA template strand and starts making its RNA copy.

The newly formed RNA undergoes modification in eukaryotes before serving as a template for protein synthesis. However, in prokaryotes, the process of transcription and translation can occur simultaneously.

Answer:

a. The particular set of resources a species uses

Explanation:

A niche is described as the interaction of an individual with its environment. It is a functional position of an individual. The niche includes how an organism lives, its behavior and abiotic factors such as light, temperature, climate etc.The ecological niche is a multidimensional thought which includes the role of an individual like predation, mutualism, parasitism, competition etc. An example of niche; A bird lives on a tree and eat the fruits.

Answer:

Temperature is usually uniform throughout a cell (Ans. C)

Explanation:

Heat or thermal energy is a kinetic energy. That is connected with the random movements present in the atoms. Temperature is usually uniform throughout the cell so the most cell can not harness heat to perform work.

Heat is a type of energy which is transfer from one body to another body due to the temperature difference.

It can only perform work if it is transferred from one source which is warmer to a body which is cooler. The temperature in living organisms is usually kept very constant due to the process of homeostasis.

Most cells cannot harness heat to do work because temperatures within the cell are typically uniform, so there's no heat gradient for work to be conducted. Heat tends to be lost instead.

Most cells are not able to harness heat to perform work because heat energy is often dissipated as waste during biochemical reactions. The correct option is c. The temperature is usually uniform throughout a cell. This means that there isn't a high temperature gradient in the cell, which would be needed in order for heat to be used for work. For heat to be harnessed and used for work, there must be a temperature difference because work is done when heat flows from a hotter area to a cooler one. Without a temperature gradient, heat energy cannot be used to perform work within a cell and is instead lost to the surrounding environment.

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Answer:

Tall , Inflated and Purple are dominant

Explanation:

The given phenotypical count is as follows -

Tall, inflated pods, purple flowers- [tex]272[/tex]

Tall, inflated, white flowers - [tex]92[/tex]

Tall, flat pods, purple - [tex]88[/tex]

Dwarf, inflated, purple- [tex]93[/tex]

Tall, flat, white - [tex]35[/tex]

Dwarf, inflated, white- [tex]31[/tex]

Dwarf, flat, purple- [tex]29[/tex]

Dwarf, flat, white- [tex]11[/tex]

Total number of species

[tex]272+92+88+93+35+31+29+11\\= 651[/tex]

Let Trepresents tall allele and t represent dwarf allele , P represents allele for purple flower and p represents allele for white flower , I represents alleles for inflated flower and i represents allele for

Phenotypical ratio

Tall, inflated pods, purple flowers- TTIIPP

Tall, inflated, white flowers - TTIIpp

Tall, flat pods, purple - TTiiPP

Dwarf, inflated, purple- ttIIPP

Tall, flat, white - TTiipp

Dwarf, inflated, white- ttIIpp

Dwarf, flat, purple- ttiiPP

Dwarf, flat, white- ttiipp

Hence, Tall , Inflated and Purple are dominant allele

The dominant alleles in this cross are tall, inflated, and purple.

In this cross, the dominant alleles can be determined by analyzing the traits that appear in the offspring. By looking at the progeny, we can see that tall plants, inflated pods, and purple flowers are the most common traits. Therefore, the dominant alleles for plant height, pod shape, and flower color are tall, inflated, and purple respectively.

Answer: False

Explanation:

Protozoans are not the organism that fix nitrogen for the plants. The organism that fix nitrogen to convert it into a form which can be used by plants are known as diazotrophs.

These are bacteria and archae that fix nitrogen gas found in the atmosphere into more usable form such as ammonia.

These organism can grow without any external source of fixed nitrogen. Example: Rhizobia and azospirillium.

Answer:

Functions of the schlerenchyma tissues are as follows:

The schlerenchyma tissue supports the hard woody plants.

These tissue makes the plant hard and present at the bark of tree.

These tissue consists of lignin chemical that makes support the plant even after it is dead.

The elongation in plant is ceased by the schlerenchyma tissue.

This tissue also strengthen the plant.

Fabrics are produced from this tissue and contribute to the country economics as well.

Answer:

The correct answer is option C.

Explanation:

As the proteins are produced in the endoplasmic reticulum membrane, they amalgamate with the vesicles and then they are conducted towards the membrane's cell surface where they act as an integral membrane protein.  

The outer end will bind with the ligand and the other one will get attached towards the cytoplasm. Thus, the pinsulin in the given case will combine with the C terminus of the protein.  

Answer:

The correct answer will be option-D.

Explanation:

Calcium plays an important role in muscle contraction as they are released from the sarcoplasmic reticulum after they receive electric impulse.

Calcium triggers the muscle contraction cycle as these calcium ions bind to the troponin-tropomyosin complex. This binding exposes the myosin-binding site on the actin on which high energy myosin binds and cross-bridge is formed.

This cross-bridge formation causes the contraction of the sarcomere and therefore muscle contracts.

Thus, option-D is the correct answer.

Meiosis is a process of cell division through which four haploi cells are produced from a diploid cell. Haploid cells are those that contain a single set of chromosomes. Gametes or sex cells are haploid cells. Thus, the goal of meiosis is to generate sex cells. For this reason, when a sperm and an egg join in fertilization, their two sets of chromosome haploids come together to form a new complete diploid set, that is, a completely new DNA or genome.

Meiosis is a complex process that involves two distinct phases: meiosis 1 and meiosis 2. Each of them is composed of several stages: prophase, metaphase, anaphase and telophase.

Meiosis1: First cell division of the diploid, known as reductive, as it results in cells with half the genetic load.

Prophese1: The first step consists in preparing the DNA to become two different sets, so that the genetic material intersects and a sort of dividing line emerges in the cell.

Metaphase1: The chromosomes are located in the center of the cell and begin to separate. Random genetic distribution has already been carried out.

Anaphase1: Each string of DNA tends to a cell pole, forming two haploid poles.

Telophase1: The plasma membrane separated and gives rise to two haploid cells.

Meiosis2: Known as a duplicate phase, it resembles mitosis: two whole individuals are formed by duplicating the DNA.

Prophase2: Haploid cells created in meiosis1 condense their chromosomes and break the nuclear envelope.

Metaphase2: As before, chromosomes tend toward the middle of the cell, preparing for a new division.

Anaphase2: The genetic material tends to separate and migrate to the poles of the cell, enlisting the new process of cell division.

Telophase2: The cell membranes separate again and result in four haploid cells, each with a different distribution from the complete genetic code of the individual.

During meiosis, homologous chromosomes undergo pairing, random alignment, crossover for genetic variation, and segregation, followed by the separation of sister chromatids resulting in four unique haploid gametes.

Key Behaviors of Chromosomes During Meiosis

Meiosis is crucial for the production of haploid gametes, which are essential for sexual reproduction. In meiosis I, homologous chromosomes pair up during prophase I and subsequently align randomly during metaphase I. This results in the separation of homologous chromosomes during anaphase I. Genetic variation is introduced as these chromosomes can exchange genetic material through a process called crossover. Meiosis II resembles mitosis, where sister chromatids separate during anaphase II. This process reduces the chromosome number by half and ensures that each gamete contains a unique set of genetic information.

In summary, the behaviors of chromosomes during meiosis involve the pairing and segregation of homologous chromosomes, crossover for genetic variation, and the separation of sister chromatids, all leading to the production of four genetically distinct haploid cells.

Answer:

a. Pathogen

Explanation:

A pathogen organism is the main cause of disease in another organism. In this example, beetles just carry the fungus, which is the real cause of the infection in the pines.  So, beetles are vectors of the fungus. They also can be called "Reservoirs" or "hosts", and the fungus is the pathogen that produces the pine’s death.

Answer:

Sickle cell disease in an autosomal recessive inherited disease which is caused by the mutation in the HBB (hemoglobin-β gene) gene present on the chromosome no. 11. In sickle cell, the red blood cells become sickle shape due to the abnormal shape of hemoglobin present in it.

These sickle cells are known to form a blockage in the blood vessels thereby causing damage to the vital organs. Human spleen constantly destroys sickle cells because they get trapped in it which causes a disease called sickle cell anemia.

Sickle cell anemia is normally the problem in genetic disease which is inherited from the parents to children. When both the DNA strand has a mutation in their HBB gene then only this disease will affect the individual.