Muscles are the specialized types of tissue in the body. They work to move different parts of the body through contraction and relaxation. Biceps and triceps are present at the elbow joint. The body maintains a balance between the fast twitch fibers and slow twitch fibers as they perform different functions.
How does muscles work?Muscles are the specialized type of tissues which move the body parts by contracting and then relaxing. Muscles can pull bones, but they cannot push them back to their original position. So, muscles work in pairs of flexors and extensors. The flexor contracts to bend a limb at a joint in the body.
The biceps and triceps are the muscles which act against one another to bend and straighten the elbow joint. To bend the elbow joint, the biceps contracts and the triceps relaxes. To straighten the elbow joint, the triceps contract and the biceps relax.
The two types of skeletal muscle fibers are the slow-twitch (type I) and fast-twitch (type II) fibers. Slow-twitch muscle fibers support long distance endurance activities such as marathon running, while fast-twitch muscle fibers support quick, powerful movements such as the sprinting or weightlifting activities.
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Layer of connective tissue that surrounds a skeletal muscle is called: _________
The layer of connective tissue that surrounds a skeletal muscle is called epimysium.
The epimysium is the outermost layer of connective tissue that surrounds the entire muscle. The connective tissue sheath that covers each fascicle is known as the perimysium, and the innermost sheath surrounding individual muscle fibers is known as the endomysium. Each muscle is surrounded by the layers of connective tissue called the epimysium. The fascia, the outer connective tissue of the epimysium, surrounds and separates the muscles. Fascia is the term for a layer or layers of connective tissue. The deep fascia surrounds the epimysium and surrounds or lines other nearby structures such as blood vessels, nerves, and body walls.
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explain the relationship between the following components of a signal transduction pathway: a) ligand (first messenger) b) receptor c) second messenger
Many pathways involve second messengers, small, non-protein molecules that pass along a signal initiated by the binding of a ligand (the “first messenger”) to its receptor.
Signal transduction is the process by which a chemical or physical signal is transmitted through a cell as a series of molecular events, most commonly protein phosphorylation catalyzed by protein kinases, which results in a cellular response. Proteins that detect stimuli are commonly referred to as receptors, though the term sensor is also used in some cases. The changes caused by ligand binding (or signal sensing) in a receptor initiate a biochemical cascade, which is a chain of biochemical events known as a signaling pathway. When signaling pathways interact with one another, they form networks that allow cellular responses to be coordinated, often through combinatorial signaling events.
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Which feature would you expect to find in a population in which sexual
selection depends on male competition?
a. large males
b. large females
c. bright-colored males
d. bright-colored females
subm
Bright-coloured males are the feature which is expected to be seen where sexual selection depends on male competition(a)
What is meant by competition?Competition between living things that coexist in the same environment occurs in nature.
Animals fight for access to food, mates, water, and other biological resources.
In a static, repetitious, or unchanging environment, humans often compete for food and mates, but when these requirements are met, intense rivalries frequently develop over the pursuit of money, power, status, and notoriety.
As corporations compete with at least one other firm for the same group of clients, competition is a key component of market economies and business.
Business competition is frequently related with this concept.
In order to satisfy and achieve higher quality services or enhanced products that the firm may manufacture or develop, competition is typically encouraged within the organization.
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When tossing a two-sided, fair coin with one side colored yellow and the other side colored green, determine p(yellow). yellow over green green over yellow 2 one half
When tossing a two-sided, fair coin with one side colored yellow and the other side colored green,The probability of getting green P ( green ) = 1/2.
Pea plants are capable of self-pollination without human assistance. As beneficial as this is to plants, it complicated Mendel's research. Due to the fact that self-pollination in a plant that does not vary for a particular characteristic does not provide useful information, he wanted to prevent this from occurring and only permit cross-pollination (pollination between distinct plants).In other words, even though he didn't know in advance exactly which traits would emerge and in what proportions, he needed to regulate what traits may develop in the plants he produced.
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Answer:1/2
Explanation:
cattle live in an area where the streams are dry. for which basic need do these cattle most likely compete?
Cattle most likely to compete for water. Since these other demands can usually be satisfied in other ways, competition for water is likely to be more significant to cattle than it is for food, housing, or energy. Compared to humans, cattle display pain and damage less visibly. As a result, when cattle do display signs of distress, they are subtle. When an animal is in pain, its welfare is damaged, and it's possible that this will have an impact on its production and health. Stereotypical behavior is a sign of a cow's poor well being and their frustration at being unable to act in a way that is normal.
Oral stereotypes, which are related to nutrient and forage deficiencies, and ambulatory stereotypes, which are brought on by constrained behavior, are frequent in cattle.
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leukocyte-reduced blood products may be administered to reduce the risk of febrile reactions and what disease or condition?
Leukocyte-reduced blood products may be administered to reduce the risk of febrile reactions and Cytomegalovirus disease or condition.
What is a leukocyte-reduced blood products?Leukocyte-reduced blood products are those blood products in which the leukocytes which are the white blood cells has being removed or reduced in other to suit the treatment of a particular diagnosis.
The importance of leukocyte-reduced blood products include the following:
It reduces the risk of high fever due to blood transfusion reactions.it reduces the risk of transmitting of cytomegalovirus infection.it may help prevent alloimmunizaton to MHC (HLA) donor antigens.Learn more about leukocytes here:
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Many pollutants from coal-fired power plants are properly managed today. Which of the following is currently considered to be the biggest threat to the environment? O nitrous oxide O sulfur dioxide O oxygen carbon O dioxide methane gas
Methane gas is currently considered to be one of the biggest threats to the environment. Thus Fourth option is the answer
Methane is a potent greenhouse gas, which means it traps heat in the atmosphere and contributes to the warming of the planet. It is estimated that methane is 28 times more effective at trapping heat in the atmosphere than carbon dioxide over a 100-year time frame.
The largest sources of methane emissions are from the oil and gas industry, landfills, and agriculture (enteric fermentation in domesticated animals and manure management).
While other pollutants such as nitrous oxide, sulfur dioxide and carbon dioxide also have negative effects on the environment, methane is considered a more significant threat because of its high global warming potential.
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for a typical neuron at rest, which value would be considered a depolarization from resting potential?
The membrane resting potential is a condition where the potential difference between the cytosol and the extracellular fluid is -70 mV. At rest, the ion potential concentration is kept constant using a Na+/K+ pump.
All body cell membranes have a membrane potential that is related to the spread of Na+ and K+ ions. This membrane potential can be found in two types of cells, namely nerve cells, and muscle cells. Changes in the membrane potential are experienced by the two cells quickly.
In a resting membrane, there are charges between the outside of the membrane and the inside of the membrane. The outside of the membrane will be more positive, and the inside of the membrane will be more negative. In such circumstances, it is said that the membrane is polarized and has a resting potential (-70mV).
When the membrane is depolarized, the membrane potential moves in the direction of 0 mV towards the positive membrane potential (+30 mV). A hyperpolarized membrane has a greater negative membrane potential than when the membrane potential is ruptured or the membrane potential is depolarized. During repolarization, the membrane returns to its resting potential.
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Classify a pet dog as an autotroph
or heterotroph and as an herbivore,
carnivore, or omnivore. Explain.
Answer:
A pet dog is undoubtedly an omnivore.
Whenever you are rearing a dog, taming a dog, you will have to provide it with all the necessary food, comprising both of plant and animal proteins, carbohydrates, and other nutrients.
A pet dog is generally provided with a very common food, called pedigree , which is essentially made up of first class proteins from animals , and vitamins and minerals from plants . So, a pet dog can obviously be categorised as an omnivore, unlike the other stray dogs, feeding on meat especially.
in the cell on the left, how many chromosomes are present during prophase?
6 chromosomes are present during prophase in the cell on the left.
During prophase, each cell contains twice as many chromosomes as a parent cell would normally have. Before going through mitosis, a parent cell first copies its DNA.
Human cells, for instance, typically contain 46 chromosomes. There are 92 chromosomes total during replication.
Prophase is the initial stage of mitosis, which divides the duplicated genetic material present in a parent cell's nucleus into two identical daughter cells. The chromatin, or DNA and protein complex, that makes up the nucleus condenses throughout prophase.
The 92 sister chromatids, which are housed within the cell's nuclear envelope, start to disintegrate during prophase.
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What could be a result of a drastic increase in global carbon dioxide levels?
Select one:
O a. a bolide
O b. continental drift
O c. mass extinction
O d. an increase in biological diversity
Oe. plate subduction
Answer:
By adding more carbon dioxide to the atmosphere, people are supercharging the natural greenhouse effect, causing global temperature to rise.
answer option C
Represented by word descriptions, such as black and short-haired: a) genotype onlyb) phenotype only c) neither phenotype and genotype d) both phenotype and genotype
Only traits, also known as phenotypes characterized by adjectives like dark and short-haired.
The set of observable qualities or characteristics of an organism is known as the phenotype in genetics. The expression of an organism's genetic code and the impact of environmental circumstances are the two fundamental factors that determine an organism's phenotype. The phenotype may be further impacted by the interaction of the two elements. A species is referred to as polymorphic if there are two or more distinct phenotypes present in the same population.
When a parent passes on a dominant allele to their child, the characteristic is known as a dominant trait and manifests in the child. Phenotypes can include characteristics like eye color, hair color, immunity or susceptibility to specific diseases, as well as physical traits like freckles and dimples on the face.
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Domestic horses have a greater diversity of coat colors than that of wild horses. The process that led to a greater diversity of coat colors in domestic horses is (1) selective breeding (3) gene alteration (2) random mutation (4) natural selection
Choosing parents with specific traits to breed with one another in order to generate kids with more desired traits is known as selective breeding.
For thousands of years, humans have carefully bred a variety of animals and plants, including crop species that produce more.
There are two types of horses in this situation: domestic horses, which are raised and produced by people, and wild horses, which are found in the wild. Selective breeding, also known as artificial selection, is a method used by humans to create new offspring with suitable and desirable traits, and it can be used to explain why domestic horses have different coat colors. These breeders choose to mate two parents who have advantageous phenotypic features, resulting in offspring with the desired attributes like strength and coat color as described.
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How many codons are needed to bring one amino acid to the ribosome?
Answer:
One codon corresponds to three nucleotides. One codon translates to one amino acid.
Explanation:
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What are three factors that increase genetic diversity?
Mutation, recombination and gene migration are the three main factors that increase the genetic diversity.
Mutation is the sudden change in the normal gene sequence of the DNA. This occurs due to missed proofreading activity of the polymerase enzymes. Mutations can occur due to several reasons and they result in the synthesis of abnormal protein or no protein is formed at all.
Recombination is the process of exchange of the genetic material between the non-sister chromatids of two homologous chromosomes. This occurs during the process meiotic cell division. This results in the progeny having genotype different from their parents and these offspring are termed as recombinants.
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Axons from which neuron in the retina make up the optic nerve? a. amacrine cells b. photoreceptors c. bipolar cells d. retinal ganglion cells.
Answer:
d. Retinal ganglion cells.
Explanation:
Retinal ganglion cells are the type of neuron located in the retina that send axons out of the eye to form the optic nerve. These cells receive input from other neurons in the retina, such as bipolar cells and photoreceptors, and then transmit visual information to the brain via the optic nerve. Amacrine cells and bipolar cells also play important roles in processing visual information in the retina, but they do not make up the optic nerve.
which monomer is most commonly found covalently linked together in long chains to store carbohydrates for later use?
Plants store carbohydrates in long polysaccharides chains called starch ( different monosaccharides) [glycosidic bond = covalent bond].
Polysaccharides. an extended chain of monosaccharides linked via glycosidic bonds is known as a polysaccharide (poly- = “many”). The chain may be branched or unbranched and can comprise exclusive types of monosaccharides.
Carbohydrates are made from monosaccharides related collectively into polysaccharide chains through a sort of covalent bond called a glycosidic bond. those glycosidic bonds are fashioned in a dehydration synthesis response.
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a young boy suffers from neurofibromatosis type 1 (nf1), a genetic nervous system disorder that causes tumors to grow around nerve cells. the gene for nf1, approximately 8,400 base pairs long, is located on chromosome 11. what is the best candidate for a vector for gene therapy in this case?
The Herpes Simplex Virus is the greatest option because it can include a strand 8,400 base pairs long, the DNA enters the nucleus directly, can divide along with the cells, and especially targets nerve cells.
What is the purpose of gene therapy?Gene therapy attempts to treat illness or strengthen your body's resistance to illness by replacing a damaged gene or adding a new gene. Numerous disorders, including cancer, cystic fibrosis, heart disease, diabetes, hemophilia, and AIDS, may be treated with gene therapy.
How is it determined which diseases are suitable for gene therapy?Clinical trials are scientific investigations that aid medical professionals in deciding whether a gene treatment strategy is secure for patients. They aid medical professionals in comprehending how gene therapy affects the body. Depending on the ailment you have and the type of gene therapy being employed, your particular process will vary.
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Which of the following changes following the start codon in the mRNA would most likely have the greatest deleterious effect?A) a deletion of a single nucleotideB) a deletion of a nucleotide tripletC) a single nucleotide substitution of the nucleotide occupying the first codon positionD) a single nucleotide substitution of the nucleotide occupying the third codon position
Answer:
A) a deletion of a single nucleotide would most likely have the greatest deleterious effect.
Explanation:
The genetic code in the mRNA is read in groups of three nucleotides called codons, which correspond to a specific amino acid. A change in any of the nucleotides in a codon can cause a change in the amino acid that it codes for, which can affect the structure and function of the protein that is synthesized. The start codon is the first codon read by the ribosome and initiates translation, so it's essential for the correct initiation of protein synthesis.
A deletion of a single nucleotide would disrupt the reading frame of the mRNA, causing a frameshift mutation, and all the codons downstream of the deletion would be shifted by one nucleotide, leading to a different amino acid sequence than the original one. This would likely have a greater deleterious effect on the protein's structure and function than a single nucleotide substitution.
A deletion of a nucleotide triplet would have similar effect as a deletion of a single nucleotide, since it would also disrupt the reading frame. A single nucleotide substitution at the first codon position would change the amino acid at the start of the protein, but it may not be as disruptive as a frameshift mutation. A single nucleotide substitution at the third codon position may also cause a change in the amino acid, but it is less likely to have a significant effect on the protein's structure and function than a frameshift mutation.
Is it possible to calculate the Solute Potential without the temperature/Kelvin? if so how?
scientists discover that fish have abnormally high levels of lead in their bodies. which type of waste disposal most likely caused this phenomenon? landfills combustion composting ocean dumping
Of the four types of waste disposal, ocean dumping is the most likely cause of this phenomenon.
Ocean dumping is the disposal of waste materials into the ocean, usually from large ships. This can include anything from sewage, industrial waste, chemicals, and even radioactive materials. Unfortunately, lead from these materials can leach into the ocean and accumulate in the bodies of fish and other marine life.
Lead is a heavy metal and does not break down easily in the environment. It can be transported by water and sediment and can accumulate in fish over time. Lead can be toxic to fish, as it can damage their nervous systems and reproductive organs. In addition, lead can be transferred to humans who eat fish contaminated with lead.
The effects of ocean dumping on the environment are far-reaching and can have serious consequences. In the case of lead, the high levels found in fish are likely due to long-term exposure to ocean dumping. The best way to prevent this type of pollution is to reduce the amount of waste that is sent to the ocean.
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Which part of a eukaryotic cell contains the instructions on how to recombine the molecules in nutrients into new molecules that the cell can use?
The instructions on how to recombine the molecules in nutrients into new molecules that the cell can use are found in the DNA, which is located in the cell's nucleus.
What is DNA?DNA is the genetic material that contains the instructions for the cell's growth, reproduction, and function. These instructions are encoded in the sequence of nucleotides in the DNA. The process of recombining molecules in nutrients into new molecules that the cell can use is called metabolism, and it takes place in the cell's organelles called mitochondria, where the energy is produced. Mitochondria have their own DNA and are considered as semi-autonomous organelles. They use the information of the DNA to perform the specific function of producing energy, and the DNA in the cell's nucleus provides the overall instructions for the cell's metabolism.
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describe the benefits to both aerobic eukaryotic cells and anaerobic prokaryotic cells that may have allowed for the formation of a mutually beneficial relationship between the two different cell types to occur.
Prokaryotes include a variety of bacteria, which can be divided in archaebacteria and the eubacteria. Archaea, have no nucleus and cell organelle, and were considered as extremophiles living in severe environments.
The eubacteria embrace the general forms of bacteria which is a huge cluster of organisms that exist in an extensive range of environments like water, soil, and other organisms (e.g., human pathogens). The largest and most complex prokaryotes are the cyanobacteria, in which photosynthesis evolved
Eukaryotic cells have membrane-bound organelles. The nucleus, enclosed by a nuclear membrane, contains genetic material which which is different from prokaryotic cells (Bacteria and Archaea). Eukaryotic cells have a variety of cytoplasmic organelles and cytoskeleton.
In eukaryotes, the genetic information (contained in nucleus) is structured in a linear rather than circular pattern of DNA molecules. Nucleus is the place of DNA replication and synthesis of RNA.
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a researcher is curious if bt resistant bollworms are susceptible to an insecticide called ddt. bollworms susceptible to bt have genotype rr or rr, whereas those resistant to bt have genotype rr. bollworms susceptible to ddt have genotype tt, whereas bollworms resistant to ddt have genotypes tt or tt. in an effort to better understand how these two genes are inherited, the researcher crosses an rr tt bollworm with an rr tt bollworm to produce the f1 generation. then, the researcher crosses the f1 generation to produce an f2 generation. what proportion of the f2 generation is resistant to both bt and ddt? fill in the punnett squares by dragging and dropping alleles to the answer boxes, first to predict the offspring in the f1 generation and then to predict the offspring in the f2 generation. then fill in the blanks using the product rule. (assume that the genes that determine ddt resistance and bt resistance are on different chromosomes.)
The percentage that will be resistant to both Bt and DDT is 3/16, or 18.75%.
Cross: RRtt with rrTT
Gametes: Rt and rT
F1 cross:
rT RrTt (susceptible Bt and resistant DDT )
F1 cross with F1
Gametes: RT, RT, rT and rt
Cross :
RT Rt rT rt
RT RRTT RRRt RrTT RrTt
Rt RRTt RRtt RrTt RrTt
rT RrTT RrTt rrTt rrTt
rt RrTt Rrtt rrTt rrtt
Given are the genotypes for bollworms that are resistant to Bt and susceptible to DDT, respectively. Bollworms that are resistant to DDT are represented by TT or Tt genotype and susceptible to DDT have tt genotype.
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Which of these descriptions of the behavior of chromosomes during meiosis explains Mendel's law of independent assortmentThe two alleles for each gene separate as homologous chromosomes move apart during anaphase I.
The male gamete determines sex because each male gamete can contribute either an X or a Y chromosome.
The arrangement of each pair of homologous chromosomes on the metaphase plate during metaphase I is random with respect to the arrangements of other pairs
During metaphase I, the arrangement of the each homologous chromosome pair just on metaphase plate is random in comparison to the layouts of other pairs.
Meiosis is a form of cell division that occurs in sexually reproducing organisms and results in a reduction in the number of chromosomes inside gametes (the sex cells, or egg and sperm). Body (or somatic) cells in humans are diploid, with two sets of chromosomes (one from each parent). To sustain this condition, the sperm and egg that combine during fertilisation must be haploid, meaning they have a single chromosome set. During meiosis, every diploid cell divides twice to produce four haploid daughters cells — the gametes.
Alleles segregate, meaning separate, during meiosis, such that each gamete has an equal chance of receiving either of the two alleles existing in the diploid person. Mendel referred to this phenomenon as the law of segregation, which might also be seen in a monohybrid cross.
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If nondisjunction, a process in which the homologous chromosomes fail to separate, occurs during meiosis I,
If nondisjunction, a process in which the homologous chromosomes fail to separate, occurs during meiosis I, the offspring will either have one too many or one too few numbers of chromosomes.
Chromosomes are thread- suchlike structures set up within the nexus of both beast and factory cells. Each chromosome is composed of protein as well as a single patch of deoxyribonucleic acid( DNA). DNA, which is passed down from parents to seed, contains the specific instructions that distinguish each living critter. The word chromosome is deduced from the Greek words for color( hue) and body( bodies)( soma). Chromosomes were given this name by scientists because they're cell structures or bodies that are heavily stained by some various colorings used in exploration. The chromosome's unique structure keeps DNA tightly wrapped around spool- suchlike proteins known as histones. DNA motes would be too long to fit inside cells if they weren't packaged in this manner.
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Reduction of fluid losses at the kidneys due to the retention of Na+ is the action of antidiuretic hormone. calcitonin. aldosterone. cortisone. oxytocin.
Reduction of fluid losses at the kidneys due to the retention of Na+ is the action of aldosterone.
What is aldosterone?Aldosterone is the primary mineralocorticoid steroid hormone generated by the adrenal cortex's zona glomerulosa. It is required for salt retention in the kidney, salivary glands, sweat glands, and colon. The effect of aldosterone is to reduce fluid losses in the kidneys due to Na+ retention. The adrenal cortex produces steroid hormones (the outer layer of the adrenal gland). It regulates the water and salt balance in the kidney by keeping sodium in and releasing potassium from the body. Excess aldosterone can result in elevated blood pressure and fluid buildup in bodily tissues.
Here,
The effect of aldosterone is to reduce fluid losses in the kidneys due to Na+ retention.
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which type of plasma membrane transport is used for gas exchange?
Simple diffusion; best because liquids and gases can both pass through.
The cell membrane is a biological membrane that separates and shields the interior of all cells from the external environment. It is also referred to as the plasma membrane (PM), cytoplasmic membrane, or plasmalemma (the extracellular space). The cell membrane is made up of a lipid bilayer, which is two layers of phospholipids interleaved with cholesterol (a lipid component) to maintain the proper fluidity of the membrane at varying temperatures.
In a living thing's anatomy and physiology, particularly in relation to homeostasis, diffusion is crucial. It is one among the mechanisms the body uses to control how much of a material is present. Without it, biological molecules, ions, and other substances won't be able to easily and quickly flow down their concentration gradients.
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Living things should be compared and classified by genetic similarities, suggesting that very different living organisms are biologically related.
Living things should be compared and classified by genetic similarities, suggesting that very different living organisms are biologically related by evolutionist.
The theory of evolution is referred to as evolutionism. Its precise definition has evolved throughout time as the science of evolution has advanced. It was used to characterise the concept in the nineteenth century that organisms consciously developed themselves via gradual hereditary change.
Natural selection, according to evolutionists, is the mechanism by which all organic life evolves from generation to generation. This notion is the foundation of evolutionist theories. The three fundamental components of Charles Darwin's theory of evolution were that variation occurs randomly among members of a species, that an individual's features could be transmitted by its descendants, and that the battle for survival would allow only those with advantageous traits to survive.
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what is cell explain breifly
Answer:
Explanation :-
In biology, the smallest unit that can live on its
own and that makes up all living organisms
and the tissues of the body. A cell has three
main parts: the cell membrane, the nucleus,
and the cytoplasm. The cell membrane
surrounds the cell and controls the substances
that go into and out of the cell.