Answer:
Adding tin to copper during melting changes the properties of the metal. The larger tin atoms restrict the movement of the copper atoms, making the material harder.
Explanation:
Please brainliest
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:
Solar panels generate electricity using photovoltaic cells that receive sunlight. To protect these cells from moisture while allowing sunlight to pass through, engineers must design a cover for the solar panel that is—
Answer:
waterproof and transmits light.
Explanation:
Answer:
Photovoltaic
Explanation:
It must be able to allow the electric flow because it must allow the electricity through that cover.
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:
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.
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.
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
The data in the diagram is evidence that -
Answer: G. Horses slowly developed over time
Explanation:
14. Scientists have found fossils of tropical plants in Antarctica. How could tropical plants
have grown in Antarctica?
a.At one time , earths entire surface was a tropical forest
b.At one time , Antarctica was located closer to the equator
c.Catastrophic volcanic eruptions melted the ice and exposed the soil to sunlight
Mediterranean forests, dry woodlands, and shrublands often have plants called sclerophytes living in them. What adaptation do these plants have that help them survive in this biome?
Answer:
he special characteristics that enable plants and animals to be successful in a particular environment are called adaptations. Camouflage, as in a toad's ability to blend in with its surroundings, is a common example of an adaptation. The spines on cycad leaves, keep animals from eating them.
Explanation:
Plants adapt to their environment from necessity. Plants may also adapt by growing lower and closer to the ground to shield themselves from wind and cold. Desert environments may have some of the following adaptations, these help the plant to conserve food, energy and water and still be able to reproduce effectively.
DESCRIBA EL CLIMA DESÉRTICO
Which of the following can NOT be cloned?
a. A dog
b. A rock
c. A bacterium
d. DNA
How are increased CO2 levels and increased temperatures affecting plant growth in the two experiments shown?
High CO2 levels cause plants to thicken their leave ,which could worsen climate change effect researchers says.
plant scientists observed that when CO2 levels increase in the atmosphere most plants do unusual , they thicker their leave
germination increase in high temperature up to the point
Increased CO2 levels and temperatures affect plant growth by bringing about a corresponding increase.
What is Photosynthesis?
This the process in which plants manufacture their food through the presence of sunlight.
other compounds such as CO2 and water are used which is why increase in the CO2 levels and temperatures will increase the growth of plants.
Read more about Photosynthesis here https://brainly.com/question/19160081
a. What is found in the troposphere?
Answer:
the troposphere contains three-quarters of the mass of the entire atmosphere. The air here is 78% nitrogen and 21% oxygen. The last 1% is made of argon, water vapor, and carbon dioxide.
Explanation:
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 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
I need help, please.
Answer:
Explanation:
I dont get the question its just a chart
why does DNA never leave the nucleus
Answer:
DNA cannot leave the nucleus because that would risk it getting damaged.
A Three-leaf clover is dominant (T) to four leaves (t). What is the probability of an offspring having 4 leaves when you cross a heterozygous clover with a four-leaf clover?
O 25%
O 50%
O 75%
O 0%
Answer:
%50
Explanation:
Heterozygous = 2 different alleles (Tt)
4 leaf clover = 2 recessive alleles (tt)
T is dominant over t, so with the combination of Tt three leaves are expressed, rather than four leaves
For a recessive trait (four leaves) to show 2 recessive alleles are needed
To find the percentage of the offspring to have four leaves a punnet square should be created
To find the percentage divide the number of four leaf offering with 4 and multiply by 100
2÷4×100=50
= 50%
Why are cells of different shapes and sizes? Give suitable examples.
Answer:
Some cells are different shapes as they have different ways of attempting to pass through the immune system they are different sizes as some of them want to make sure that the white blood cells cannot swallow them as easily at that point antitoxins are released to break them down
Explanation:
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:
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.
which statement is not part of cell theory ?
Answer:
option (C) is your answer
I hope it's helps you
Answer:
C.
Explanation:
I am so sorry if I'm the wrong answer.
_______________, 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.
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
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: (:
The population of Dubai at the end of 2012 was 2.1 million. This was predicted to increase at a rate of 6% each year. Calculate the predicted population of Dubai at the end of 2015?
Mathematics
Answer:
2.1×0.06^3= the correct answer
Explanation:
using a compound formula used for interest u can use this to see how the population is increasing by multiplying the principal×rate^time
Answer:
Population at the end of 2015 is 2.5 million.
Explanation:
Population of Dubai at the end of 2012 is 2.1 million.
Rate of increase of population is 6%
Population at the end of 2013 is 2.1 million +(6% of 2.1 million) =2.226 million.
Population at the end of 2014= 2.226 million + 6% of 2.226 million = 2.35956 million.
Population at the end of 2015 is = 2.35956 million + 6% of 2.35956 million = 2.5 million.
Hope this answer helps you :)
Have a great day
Mark brainliest
A Punnett square is a type of model. Which type of model does this Punnett square represent?
a)conceptual
b)functional
c)mathematical
d)physical
Answer:
c
Explanation:
it uses percentages, like 50% Aa, 25% aa and 25% AA
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 processes causes
sinkholes to form?
A. erosion of sediment by runoff
B. deposition of sediment by a river
C. deposition of calcite by groundwater
D. erosion of limestone by groundwater
Answer:
A. erosion of sediment by runoff
Explanation:
The formation of sinkholes involves natural processes of erosion or gradual removal of slightly soluble bedrock (such as limestone) by percolating water, the collapse of a cave roof, or a lowering of the water table. Sinkholes often form through the process of suffosion.
Answer:
A sinkhole is a hole in the ground that forms when water dissolves surface rock. Often, this surface rock is limestone, which is easily eroded, or worn away, by the movement of water. ... Water collects in these collapsed sections, forming sinkholes. Sinkholes also form when the roofs of caves collapse.
