Answer:
Breeders can increase the genetic variation in a population by inducing mutations, which are the ultimate source of genetic variability
The immune system has both specific and nonspecific defenses against viral infections. Which statement describes a nonspecific response of the immune system in fighting viral infections?
A. T cells are produced to search out and destroy the viruses.
B. Memory B cells are activated to rapidly respond to the viral infection.
C. Plasma cells quickly replicate and release antibodies that bind to the viruses.
D. Virus-infected cells produce interferons that lead to the inhibition of viral replication
Answer:
C
Explanation:
I just did this same question
Virus-infected cells produce interferons that lead to the inhibition of viral replication and act as a nonspecific response of the immune system in fighting viral infections. Therefore, the correct statement is option D.
What are interferons?The immune system has two types of responses to viral infections: specific and nonspecific. Interferons are signaling molecules produced by virus-infected cells to activate antiviral defenses, such as apoptosis in infected cells. This refers to the nonspecific response of the immune system in fighting viral infections
Interferons function by alerting the immune system about the presence of a viral infection. Interferons can also stimulate the production of other immune cells, such as natural killer cells and macrophages to eliminate the infected cells.
Interferons have been also used to treat viral infections, such as hepatitis B, and are the nonspecific defenses that act as a first line of defense against viral infections.
Therefore, interferons that lead to the inhibition of viral replication are the nonspecific response of the immune system in fighting viral infections.
Learn more about the interferons here:
https://brainly.com/question/31376665
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1. How many layers are there in an arthropod's exoskeleton? What is the main function of
each layer?
Explanation:
The exoskeleton and molting
The success of arthropods derives in large part from the evolution of their unique, nonliving, organic, jointed exoskeleton (see figure), which not only functions in support but also provides protection and, with the muscle system, contributes to efficient locomotion. The exoskeleton is composed of a thin, outer protein layer, the epicuticle, and a thick, inner, chitin–protein layer, the procuticle. In most terrestrial arthropods, such as insects and spiders, the epicuticle contains waxes that aid in reducing evaporative water loss. The procuticle consists of an outer exocuticle and an inner endocuticle. In the exocuticle there is cross-bonding of the chitin–protein chains (tanning), which provides additional strength to the skeletal material. The hardness of various parts of the exoskeleton in different arthropods is related to the thickness and degree of tanning of the exocuticle. In crustaceans, additional rigidity is achieved by having the exoskeleton impregnated with varying amounts of calcium carbonate.
arthropod integument
arthropod integument
Diagrammatic section through the arthropod integument.
Encyclopædia Britannica, Inc.
The formation of an exoskeleton required the simultaneous solution of two functional problems in the evolution of arthropods: If the animal is encased in a rigid covering, how can it grow and how can it move? The problem of growth is solved in arthropods by molting, or ecdysis, the periodic shedding of the old exoskeleton. The underlying cells release enzymes that digest the base of the old exoskeleton (much of the endocuticle) and then secrete a new exoskeleton beneath the old one. At the time of actual shedding, the old skeleton splits along specific lines characteristic of the group, and the animal pulls out of the old skeleton as from a suit of clothes. The old skeleton is usually abandoned but in some species is eaten. The new exoskeleton, which is soft and flexible, is then stretched by localized, elevated blood pressure augmented by the intake of water or air. Hardening occurs by stretching and especially by tanning within a number of hours of molting. In crustaceans, calcium carbonate is deposited into the new procuticle. (Soft-shell crabs are simply newly molted crabs.) Additional endocuticle may be added to the exoskeleton for some days or weeks following molting.
molting
molting
Grasshopper shedding its exoskeleton.
© Cathy Keifer/Dreamstime.com
Molting is under hormonal control, and there is a long preparatory phase that precedes the process. The steroid hormone ecdysone, secreted by specific endocrine centres and circulated in the blood, is the direct initiator of molting. The actual timing of a molt, however, is regulated by other hormones and commonly by environmental factors. The interval between molts is called an instar. Because of the frequency of molts, instars are short early in life but grow longer with increasing age. Some arthropods, such as most spiders and insects, stop molting when they reach sexual maturity; others, like lobsters and crabs, molt throughout their lives. Most of the larger spiders of temperate regions, for example, molt about 10 times before reaching sexual maturity. As a result of molting, the length and volume of an arthropod display steplike increases over the life span, but internal tissue growth is continual as in other animals.
Loss of a limb is a common hazard in the life of many arthropods. Indeed, some arthropods, such as crabs, are capable of amputating an appendage if it is seized by a predator. The limb is then regenerated from a small, nipplelike rudiment formed at the site of the lost limb. The new limb develops beneath the old exoskeleton during the premolt period and then appears when the animal molts.
Answer:
Three layers
Explanation:
Outer= Composed of proteins and lipids. Repels water and prevents desiccation in terrestrial places.
Middler=Provides primary protection
Inner=Flexibke at joints, muscles attach here.
A student is studying calcium, a highly reactive element that humans need for strong bones. Which characteristic of calcium is most closely related to its chemical reactivity?
Explanation:
it's very reactive which helps to make strong bones
Which of the following can NOT be cloned?
a. A dog
b. A rock
c. A bacterium
d. DNA
DESCRIBA EL CLIMA DESÉRTICO
The data in the diagram is evidence that -
Answer: G. Horses slowly developed over time
Explanation:
1) ¿como se forma la capa de ozono y que la destuye?
2) ¿Cuál es la función del campo magnético terrestre, de que nos protege?
Answer:
Ozone molecules in the stratosphere are constantly being produced and destroyed by different types of UV radiation from the sun. ... However, scientists have discovered that certain chemicals react with UV radiation in the stratosphere, which causes them to break apart and release chlorine or bromine atoms.
Explanation:
As an embryo developed, identical cells give rise to specialized cells that platform different functions.
Answer:
As an embryo develops, identical cells give rise to specialized cells that perform different functions.
Explanation:
As an embryo develops, the cells divide, giving new ones. As the cells grow and continue to reproduce themselves, they differentiate, becoming specialized cells. These cells will be located in a particular part of the embryo and will perform a specific function. The shape, size, and organelles vary according to their role.
Carbon dioxide is least soluble in ocean water
A .None of these answers are correct.
B . in the Arctic Ocean.
C .in the North Atlantic Ocean.
D . near the South Pole.
E . at the equator.
Answer:
it's either be or see because it's more soluble with water the sense the Arctic Ocean is you know near the Arctic which would be like more North Pole and it be really cold and Frozen it's more contact with just normal water so I'm pretty sure the North Atlantic Ocean so c
The early ancestors of horses showed the presence of digits on their limbs, while modern horses have hooves. What are likely possible reasons for this change?
Answer:
Natural Selection & Fitness
Explanation:
Horses have evolved to run as fast as possible because they are prey animals.
The hooves give advantages to the predecessors to the modern horse rather than the foot-bearing horses.
Thus when somebody inevitably becomes a snack, the hoof bearing horses lived longer. (Natural selection)
Because they've lived longer, they've had more babies. (Fitness)
Their babies are more likely to pass on the genes they've inherited from their successful parents, and the population of hooved-horses begins to exceed the population of footed-horses.
In this circumstance, all the footed-horses are gone. The population has evolved.
Hope this helps <3
PS: here's a source! https://www.amnh.org/exhibitions/horse/the-evolution-of-horses/on-your-toes#:~:text=Hooves%20and%20long%20legs%20help,many%20horses%20retained%20three%20toes.
_______________, such as bacteria, breakdown dead organisms and release nutrients back into the soil.
A. Producers
B. Decomposers
Answer:
B. Decomposers
Explanation:
i hope this helps ;)
Decomposers,such as bacteria, breakdown dead organisms and release nutrients back into the soil.
Whích DNA strand is complementaryto the DNA strand TAC CTA AGT GCA
A. ATG GAT TCA CGT
B. GTA TAG ACT TGC
C. GGG CAG CAG GAT
D. TCA CGT GAT ATG
Answer: A
Explanation:
G is opposed to C
And C is opposed to G
T is opposed to A
And A is opposed to T
I'll mark brainliest...
Give the scientific term for each of the following descriptions.
2.1 The phase in which chromatids are separated
2.2 The phase where chromatids are formed
2.3 Plant tissue responsible for mitosis
2.4 The stage of cell division in which the DNA is copied
2.5 The cellulose structure that divides a plant cell into two during telophase
2.6 The two structures that make up a centrosome
Answer:
2.1: Anaphase
2.2: synthesis phase
2.3: Meristematic tissue
2.4: Interphase
2.5: cleavage furrow
2.6: pericentriolar material
Explanation:
What element is part of the Alkaline Earth Metals family and located on period 4
Potassium
Bromine
Calcium
Krypton
Answer:
C. Calcium (CA)
Explanation:
other Alkaline Earth metals in period 4 are, beryllium (Be), magnesium (Mg), strontium (Sr), barium (Ba), and radium (Ra)
Answer:
calcium is part of the alkaline earth metals family
why does DNA never leave the nucleus
Answer:
DNA cannot leave the nucleus because that would risk it getting damaged.
Which of the following is a density dependent limiting factor? NO LINK ANSWERS
A. new construction by humans in environment
B. earthquake
C. a sudden flood in the environment
D. new predator's in the population
The SWAG scientist wrote this description (in the picture below) of a cell after looking at it under the microscope. Which type of cell was the student most likely describing?
answers:
Animal cell
Bacterial cell
Plant cell
Prokaryotic cell
Answer:
I think bacterial cell becausea microscope look into small organisms that we can't see with a naked eye
which one is it I am confused A,B,C or D
Answer:
I think option B is right answer
Answer:
B) Image 1 -> Image 3 -> Image 4 -> Image 2
Explanation:
The pictures of the ecosystems are needed to be put into the simplest -> complex order.
Image 1 could be the simplest as it only has one organism.
Image 3 would be the next simplest as it has only a group of the same organism.
Image 4 would come next as it has aqua life and surroundings but the same fishes!
Image 2 would be the most complex, as it has various biodiversity and surroundings!
The order would go as Image 1 -> Image 3 -> Image 4 -> Image 2.
How does human consumption of limited resources impact the biosphere? 1 paragraph
Answer:
Human use of land has negative impacts. Human activities contribute to the erosion and pollution of beaches. ... More of the rainwater runs off leading to increased erosion and drier soil. Deforestation of land can also lead to desertification and a loss of biodiversity.The burning of fossil fuels and the growth of animal agriculture has led to large amounts of greenhouse gases (such as carbon dioxide and methane) in the atmosphere. Higher concentrations of greenhouse gases trap more heat in the biosphere and result in global warming. In turn, this drives climate change.Humans affect the quality, availability, and distribution of Earth's water through the modification of streams, lakes, and groundwater . ... The activities of humans have significantly altered the biosphere , changing or destroying natural habitats and causing the extinction of many living species.
Explanation: (:
I need help, please.
Answer:
Explanation:
I dont get the question its just a chart
what do we call the flight in bees whereby mating occurs and drones are killed after mating the queen?
Answer:
The next male honey bee to mate with the queen will remove the previous endophallus and eventually lose his own after ejaculation. Male honey bees are only able to mate seven to 10 times during a mating flight, and after mating, a drone dies quickly, as his abdomen rips open when his endophallus is removed
Answer:
I don’t know
Explanation:
At all
If only one species is considered the 'fittest', why do we still have so many variation among species?
Answer:
Variation occurs in species with the genes resulting in the traits and physical characteristics that make it possible for them to be among the fittest for a number of reasons:
1. Mutation
2. Recombination and
3. Migration
Explanation:
Mutations: A mutation is a deviation from the norm in a DNA sequence. It can be stimulated by errors during the DNA replication process which happens as the cell is dividing, or by exposure to ionizing radiation, chemicals, or viral infection (whether artificial or natural).
It is noteworthy that naturally, without any human intervention, the possibility of a spontaneous mutation is very low.
Recombination: This refers to the creation of new fusion of genes in the offspring that did not occur in the parents by the processes of crossing-over and independent assortment. Independent assortment meaning that the allele the gamete received for one gene was not influenced by the allele received for another gene.
Migration: Variation by migration here refers to the introduction of new genes from into one population by another. This could happen when a new population arrives at an existing one or when an existing one migrates to another population.
We can say for example that, genes from Americans have “migrated” into the population of African origin in America given the continuous immigration of Africans into America.
So in both populations, there are very fit species, but when their genes are mixed during cross-reproduction, variation arises.
Cheers
Question 1
5 pts
What are two factors that increase the genetic variation in a population?
O Mutations and mitosis
O Budding and meiosis
O Crossing over and mutations
O Crossing over and mitosis
Answer:
The second one and the third
Explanation:
Part C When a material is heated, the change in temperature depends on the kind of material and its mass. Different objects can absorb and release different amounts of energy when heated and cooled. This property is called heat capacity. How might scientists apply this property to design something useful in the real world? Give one or two examples.
Answer:
Not really sure about this question but what I think is,
So for example, metal..Metal has a very low specific heat capacity, but we use it pretty much in all our lifetime right? Things that have low heat capacity have very high capacity if that makes sense. Things like water and oil, they take more energy to get heat up or get hot. Its funny because its what makes our planet survivable. 70% of our planet is of course water and radiation (light and heat) from the sun strikes 70% of water. Meaning its not heating anything up so quickly. Hope this somewhat helps you out and gives you an idea on what the question is talking about :) Enjoy!
Explanation:
Answer:bsna
Explanation:
The human population is in an era of
growth.
O A. linear
B. slowing
O C. exponential
Answer:
C
Explanation:
because the human population is constantly rising and it has become a problem because we are using up our resources. linear means it stays the same. slowing means it's going down more than up and exponential means it is continuously going up
Which of the following is NOT an effective water conservation
echniques?
a. Using low flush toilets
b. Public outreach campaigns
C. Using showerheads that limits water flow to 4.5 gallons per day
d. Mulching around trees and plants
e. Having large production monoculture farms
Answer:
e
Explanation:
It worsens the quality of the soil
Please help me. no links I will report you
Please answer fast for the 20 points.
Answer:
Request a refund for recent purchases · It's less than 48 hours since you bought an app or made an in-app purchase,
Answer:
D. several million years
Explanation:
find the velocity of the spacecraft:
6 ÷ 2 = 3 AU per year
the time for the spacecraft to travel to Wolf 359:
492,000,000 ÷ 3 = 164,000,000 = several million years
can exoskeletons break?
Drag four of the terms to the space below the matching image
Answer:
The order they go is (from left to right)
Organ system, Organism, Organ, Cell
Explanation:
A organism is made of multiple organ systems like humans (respiratory system, cardiovascular system, etc.)
A organ system has multiple organs like veins, heart, etc.
A organ is made of lots of cells
A cell is the unit of life.
Special cells in the body are responsible for gathering information about the body's environment. These cells are called receptor cells. The information gathered by receptor cells is encoded as electrical signals that travel along the body's nerve cells. The brain and spinal cord then process the electrical signals to determine how the body should respond.
Suppose information gathered by a group of receptor cells has just been processed by the nervous system. Which of the following could happen next?
Answer:
A reflex action
Explanation:
Answer:
The information could trigger an immediate behavior. The information could be sent back to the receptor cells.
Explanation:
Brainiest please :D
