Answer:
"Activation of CD4+ helper T cells" is the correct choice.
Explanation:
The major complicated of histocompatibility II seems to be the chemical compound for something like the T cells that presets antibodies. Antigens collected from those in the pathogens become transformed as well as inserted into a large histocompatibility system that's also distributed on either the cellular cell surface membrane representing antigen as well as the trigger is perceived by complicated systems of T cells as well as MHC II but rather contained throughout CD4 + support T cells.The ostrich is a bird. However, it has traits that are different from those of the birds we typically see flying around our neighborhoods. Using credible sources, investigate the environment and adaptations of ostriches to explain how they evolved to survive in their environment.
Answer:
According to National Geographic, ostriches are a part of a very small group of birds that cannot fly because unlike most birds, their small wings are not strong enough to carry their body for flight and their breastbone isn't balanced enough for flying. Birds that are unable to fly are called ratites.
A number of scientists namely Thomas Huxley, Richard Owen, and others have tried to show that these ratites are actually related to each other and eventually, it was discovered that they all had one thing in common, the way the bones at the roof of the mouth were arranged was similar to that of reptiles rather than other birds.
Richard Owen found and assembled the remains of an extinct ostrich skeleton which was an extinct moa and contrary to already held opinion, one ratite known as tinamous did not really fit with the profile of a ratite because it could fly, even though almost grudgingly and they possessed keeled sternum which suggests that they evolved from flying birds.
DNA tests showed that tinamous evolved within ratites and not necessarily as a separate entity. The tests also showed that moas and tinamous are related.
It was also speculated that the division of the supercontinent Pangaea southern side led to the separation of flightless ratite ancestors, causing each landlocked group to evolve and become the flightless birds we know today such as the ostrich, rheas, etc.
Answer:
An ostrich is an extremely large bird that lives in Africa. It can’t fly, but it has powerful legs that allow it to outrun most predators. Its flexible knees and two-toed feet enable it to run easily. An ostrich has strong leg muscles that it can use to kick large predators. It has claws on its wings to defend itself from predators and thick feathers to keep it warm at night. Ostriches have thick eyelids that protect their eyes from sandstorms.
Explanation:
HEEELLLPPP PLSS!!! Compare and contrast open, closed, and isolated systems. Be sure to discuss the exchange of energy and exchange of matter, and provide at least one example of each.
Answer:
See the answer below
Explanation:
An open system is a type of thermodynamic system in which energy and matter are being exchanged between the system and the surrounding. It is like boiling soup in an open pot. The opening allows for the addition of materials (matters) into the soup and energy is exchanged through the heating. A good example is found in biological organisms. They consume matters and exchange energy with the environment by carrying out work.
A closed system is a type of system in which there is no exchange of matter between it and the environment. However, there is an exchange of energy. It is like boiling water in a closed pot. Nothing can be added into the pot due to the closure but energy can be transferred through the heating of the pot.
An isolated system allows for neither energy nor matter exchange with the surrounding. It is like a closed food warmer that allows for nothing to enter or leaves it.
Answer: Open systems are energy that can be transferred between the system and its surroundings. Close systems are systems that do not transferred to its surroundings. Isolated systems is a thermodynamic system which cannot exchange either energy or matter from outside its boundaries of the system.
Hope this helps:)
List three protozoan infections of the circulatory system that are transmitted by arthropods. Include the disease name, specific organism (genus species), vector that is the intermediate between hosts, and disease progress in humans.
Answer:
List three protozoan infections of the circulatory system that are transmitted by arthropods:
Malaria
Toxoplasmosis
Chagas disease (American trypanosomiasis)
Explanation:
Malaria is a prozotoan infection, that can be produced by several protozoan, in the genus Plasmodium. This Plasmodium infect red blood cells and the vector that trasmites it is the Anopheles mosquitoe. In this disease, red blood cells can have severe damage in different organs because of the hemolysis.
Toxoplasmosis is a disease caused by the protozoan Toxoplasma gondii. The main vector of them are domestic cats. When cats are infected, T. gondii oocysts is found in their feces and it can spread to humans. This disease is generally asymptomatic, except when the patient has AIDS or in pregnancy, which can be very dangerous and fatal.
Chagas disease, or American trypanosomiasis is caused by protozoan Trypanosoma cruzi and is generally transmitted to people thanks to the feces of triatomine bugs. Some of the acute symptoms include fever, vomiting, headache, and in severe cases people can develop a chronic disease. In the worst cases it can produce flaccid cardiomegaly (enlargement of the heart) leading to heart failure and death.
Choose only one correct option. Explanation needed.
Answer: D
only green plants
Answer:
[tex]\large \boxed{\mathrm{D. \ Photosynthesis}}[/tex]
Explanation:
Photosynthesis is a characteristic present in plants. Photosynthesis is a process where plants transform light energy into chemical energy. Reproduction, respiration, and excretion are all characteristics of living organisms.
Shell coiling in some snails has been found to be determined by the genotype of the snail's mother, rather than its own genotype. This is termed:
Answer:
maternal effects
Explanation:
The correct answer would be maternal effects.
The maternal effect is a genetic phenomenon that is characterized by an organism having the phenotypic expression that is compatible with the genotype of its mother irrespective of the organism's genotype itself.
This condition often occurs as a result of the mother supplying messenger RNA or protein to the egg that results in the formation of a zygote/embryo. Consequently, the genome of the mother dictates the functionality of the molecule in such offspring.
Which of the following describes the most likely impact that exposure to pollutants in the atmosphere would have on one’s personal health?
Answer:
It will lead to upper respiratory infections and pneumonia.
Explanation:
Which is a feature of a tonic receptor? Select one: a. The action potential occurs when there is a change in response to a change in condition. b. For this receptor, the stimulus begins with a burst of action potentials. c. They are normally inactive. d. When the stimulus changes the action potential generation changes. e. Provides information about the rate and change of the stimulus. f. The action potential is generated for a short time period.
Answer:
For this receptor, the stimulus begins with an explosion of action potentials.
that would be the correct option.
Explanation:
A tonic receptor is one that is activated when the action potentials were maintained over time and during the signaling of the receptor.
Tone receptors require continuous stimulation over a period of time to trigger a response and deliver it to the central nervous system.
It keeps the nervous system constantly active in the environment that surrounds it.
They are slowly adaptable, an example of these receptors are the merkel and ruffini receptors.
ASAP What is a photosynthetic pigment? What is a photosynthetic pigment? A. An oxygen based compound that captures light energy. B. A light sensitive compound that changes color. C. A colored compound that captures light energy. D. A manmade compound that reacts to light.
I think the answer is A.
Answer:
A. An oxygen based compound that captures light energy.
is the basic unit of structure and function of living things.
Answer:
cells
Explanation:
is the basic unit of life :)
blood consists of which fluid medium
a.lymph
b.platelets
c.plasma
d.all of these
Answer:
C. Plasma
Explanation:
Blood consists of a fluid medium called Plasma.
Identify the organelle where photosynthesis takes place.
B
C
D
E
Answer:
E
Explanation:
If E is the Chloroplasts, where photosynthesis takes place, then the answer is E.
Answer:
E
Explanation:
Which conclusion can be drawn from the experimental observation that a single strand of DNA contains 2100 dA residues and 1800 dT residues?
a. There must have been some loss of material in the extraction because the number of dA and dT residues must be the same.
b. This is a palindromic sequence.
c. There must be 2100 dT and 1800 dA residues on the complementary strand.
d. This must be prokaryotic DNA
e. None of these
Answer:
c. There must be 2100 dT and 1800 dA residues on the complementary strand.
2. Name the sympathetic ganglia in which the preganglionic and postganglionic neurons synapse.
Answer:
The paravertebral ganglia is the sympathetic ganglia where the pre-ganglionic and post-ganglionic neurons synapse.
Explanation:
Which of the following is an example of a non-mendelian pattern of inheritance? A) all traits are inherited through patterns found by Mendel. B) when individuals with the genotype BB cross, all the offspring have brown fur. C) when pea plants that are hetero-zygous for a certain trait cross some of the offspring express both distinct versions of the trait. D) when horses that are homo-zygous for red hair are crossed with horses that are homo-zygous for white hair, the offspring have both red and white hair.
all of the following are examples of organic matter soil except
This question is incomplete; here is the complete question:
All of the following are examples of organic matter soil except
A. Decaying plants
B. Bacteria
C. Fungi
D. Water
The answer to this question is D. Water
Explanation:
Organic matter derives from living beings, due to this, organic matter is considered as a biological product. In this context, materials such as decaying plants are organic matter because they derive from living organisms and contain biological molecules (most contain carbon). This category does not apply to water, which is composed of hydrogen and oxygen and does not derive from living beings. Thus, the one that is not organic matter is water.
Answer:
D. Water
Hope this Helps!! :))
Biochemical and genetic experiments have demonstrated that the _________ of tRNA are important for recognition by its cognate aminotransferase-tRNA synthetase.
Answer: Acceptor stem and anticodon loop.
Explanation:
Transfer RNA (tRNA) is a small RNA nucleic acid involved in protein synthesis (translation). Each tRNA molecule has two important areas:
A region of trinucleotides, called the anticodon A region where a specific amino acid binds.During translation, the ribosome reads the sequence of the mRNA in groups of three bases to assemble the protein. So, in the mRNA chain there are codons, set of three bases, which determine the amino acid to be added to the peptide chain. The tRNA transfers the amino acid to the ribosomes, and then arranges them along the messenger RNA (mRNA) molecule. Then, the tRNA must have an anticodon that is complementary to the codon. Each type of tRNA is specifically combined with 1 of the 20 amino acids to be incorporated into proteins.
This means, during translation, each time an amino acid is added to the growing chain, a tRNA molecule is formed whose base pairs have a complementary sequence with mRNA molecule, ensuring that the appropriate amino acid is inserted into the protein. So, tRNA is a key link between RNA transcription and the translation of that RNA into protein. On the other hand, aminotransferases are enzymes responsible for attaching amino acids to the 3ʹ‐end of cognate tRNAs.
The acceptor stem is the site of attachment of amino acids to tRNA, and anticodon loop is the site of tRNA that is complementary to the codons found in mRNA (that determine the amino acid that will be added) This means, both parts are important for recognition, because the acceptor stem is where the amino acid is, and the anticodon loop ensures that the appropriate amino acid is inserted into the protein.
When a bacterium such as E. coli is shifted from a warmer growth temperature to a cooler growth temperature, it compensates by
Question is incomplete, The complete question is as follows:
When a bacterium such as E. coli is shifted from a warmer growth temperature to a cooler growth temperature, it compensates by:
A) increasing its metabolic rate to generate more heat.
B) putting longer-chain fatty acids into its membranes.
C) putting more unsaturated fatty acids into its membranes.
D) shifting from aerobic to anaerobic metabolism.
E) synthesizing thicker membranes to insulate the cell.
Answer:
C) putting more unsaturated fatty acids into its membranes.
Explanation:
Bacteria has the ability to change the composition of fatty acid present in its cell membrane to compensate the change in temperature.
When bacterium E.Coli will shift from hight or warmer temperature to low or cooler temperature, it will put more unsaturated fatty acids into its membranes which will mintain the fluidity in the membrane.
Hence, the correct option is "C".
Which of the following is an example of reproductive isolation?
Answer:
the example of reproductive isolation is temporal isolation, ecological isolation, behavioral isolation, mechanical isolation.
Which of the following best explains the potential health problems associated with endocrine disruptors? A) Endocrine disruptors are the only available pesticides,hence they are used widely. B) Endocrine disruptors mimic hormones that regulate critical biological processes. C) Endocrine disruptors do not biodegrade, remaining toxic years after their release. D) There are no major health problems associated with exposure to endocrine disruptors. E) Endocrine disruptors encompass a wide array of toxic pesticides.
B) Endocrine disruptors mimic hormones that regulate critical biological processes.
Endocrine disruptors, at times moreover called as hormonally unique trained professionals, endocrine disturbing engineered substances, or endocrine upsetting blends are manufactured substances that can interfere with endocrine structures. These aggravations can cause threatening developments, birth flees, and other developmental issues.
The potential health problems associated with endocrine disruptors is that Endocrine disruptors mimic hormones that regulate critical biological processes.
For more information:
https://brainly.com/question/22965068?referrer=searchResults
Answer:
It's A.) Endocrine disruptors mimic hormones that regulate critical biological processes.
Explanation:
Quizlet gave me the answer
Match each part of Sammi's model to the bodily structure it represents. One bodily structure has already been labeled for you.
Answer:
corrugated cardboard tube - digestive tract
irregular surfaces on the corrugated tube - villi
pump - heart
Plastic tubing - blood vessels
Explanation:
The corrugated cardboard tube represents the digestive tract. The give away was the presence of the irregular surfaces within the tubes. This is called the villi. The villi is responsible for the absorption of food after digestion into the body.
Irregular surfaces on the corrugated tube represent the villi. They are tiny hair-like structures that are in the small intestine, that are responsible for the absorption of food into the bloodstream.
The pump represents the heart. The heart is the only organ in the body that provides the pressure force that pushes the blood throughout the body. In this model, the pump will most likely be performing the same function.
The plastic tubings are meant to contain one form of fluid or the other. Judging from that, they can be said to represent the blood vessels. This is because they are connected to the heart and are meant to transport bodily fluids around the body
Answer:
corrugated cardboard tube - digestive tractirregular surfaces on the corrugated tube - villipump - heartPlastic tubing - blood vessels
Explanation:
What are two major drivers of surface ocean current and deep ocean current? 1. Surface ocean current 2. Deep ocean current The choices are: A. Differences in water density, resulting from the variability of water temperature and salinity B. Global wind systems
Answer:
1-B 2-A
Explanation:
this is because the wind blowing over the water causes motion whereas deep water is effected by Differences in water density, resulting from the variability of water temperature and salinity
Taxonomists today tend to group organisms into the same category based on similar what?
Answer:
characteristics
Explanation:
oranisms are grouped based on shared characteristics
Taxonomists today tend to group organisms into the same category based on their evolutionary history and shared ancestry, as explained in Option A, as this allows taxonomists to construct more accurate and detailed phylogenetic trees.
What is taxonomy?The field of taxonomy is concerned with the classification of living organisms based on their shared characteristics, the aim of taxonomy is to group organisms in a way that reflects their evolutionary history and to provide a standardized system of naming, while earlier taxonomists relied on morphological characteristics, such as the physical appearance of an organism, but modern taxonomists instead use molecular and genetic data to group organisms into categories.
Hence, taxonomists today tend to group organisms into the same category based on their evolutionary histories and shared ancestry, as explained in Option A.
Learn more about the taxonomy here.
https://brainly.com/question/19184314
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The question is incomplete, complete question is below
Taxonomists today tend to group organisms into the same category based on similar what?
A)based on their evolutionary histories and shared ancestry
B)based on fossils
Carbon first enters the food web in Multiple Choice humans. vertebrates. invertebrates. green plants. soil bacteria
Answer:
Green Plants
Explanation:
Carbon enters all food webs, both terrestrial and aquatic, through autotrophs, or self-feeders.
Aquatic organisms in coastal areas face a variety of predators on land and in the water and air. Which ocean process exposes the coastal aquatic organisms to land-based predators? a. Changing wind patterns alter the ocean currents, changing tide levels. b. Daily tidal patterns leave areas exposed to the land for part of the day. c. The constant wave action generates nutrients that attract predators. d. The ocean conveyor belt raises and lowers the water levels on the coasts.
Answer:
b
Explanation:
The correct answer as to the ocean process that exposes the coastal organisms to land-based predators would be the daily tidal patterns that leave the coastal area exposed to the land for a part of the day.
Some parts of the coastal areas become exposed to land during certain periods of the day as a result of tidal waves. When this happens, the aquatic organisms occupying these coastal areas become temporarily exposed to land predators who hunt and kill them for food.
Therefore, the correct option is b.
Which of the following statements is true of soluble fibers? a. They are not viscous. b. They retain their tough texture after being cooked. c. They impart gel-like characteristics to foods. d. They always resist fermentation. e. They are tough and stringy.
Answer:
The answer is "Option C".
Explanation:
The soluble fiber was fiber and in the diet which is prescribed to increase metabolism, reduce cardiovascular problems, cure constipation, and is ideal for patient diabetes.
This consumes food water and provides support with gel-like characteristics, which are rich in fiber in foods like rice, fruits, and bovines. They all are essential for fitness, digestion, and preventive medicine. It draws in liquid(water) while absorption and transforms into a gel. It slows it down the digestive cycle.
Evidence without_______
increases its reliability.
a
bias
b
question
с
repetition
d
replication
Answer:
I'll say its B ) Question
Explanation:
because when your proving something with evidence then you start asking questions (or still have questions) makes it seem like you don't really know.
A paleontologist finds a relatively complete skeleton but isn’t sure if it is an ape fossil or a hominid fossil. Which of the following features would NOT help distinguish between the two choices?
a. position of the opening in the skull for the spinal cord
b. design of the pelvis
c. relative length of the hind limbs
d. position of the eyes
What alternate form of genes do nucleic acids have that allows them to offer variability?
Answer:
allales
Explanation:
an allele is the variant from a gene
Answer:
A. allales
Explanation:
PLS ANYONE IT'S URGENT Explain eubacteria ?
Answer:
Eubacteria are PROKARYOTIC organisms characterized by the lack of membrane and have peptidoglycan on cell wall when present.
Explanation:
They include most of the familiar bacteria such as E.
Hope it helps.
When chyme enters the duodenum, ____ is released and stimulates the pancreas to secrete bicarbonates. A. gastrin B. secretin C. insulin D. cholecystokinin E. glucagon
Answer: B. secretin
Secretin is secreted in response to acid in the duodenum, which occurs when acid-laden chyme from the stomach flows through the pylorus. The effect of secretin on the pancreas is to stimulate duct cells to secrete water and bicarbonate.
