The correct option is :
=》arteries do not have valves and veins do have valves.
Arteries don't have valves because back flow of blood isn't possible due to high pressure, but blood in veins doesn't have high pressure just like arteries, so to stop backflow of blood, veins have valves.
What is the speed of a runner who travels 20m in 10s?
Answer:
2m/s
Explanation:
speed =distance ÷time
The wings of butterflies and birds are ----------- structures because, although they are used for the same purpose (flight) they have very different structural compositions. Bird wings are made of bones and feathers while butterfly wings are made from chitin and are part of the insect’s exoskeleton.
Answer:
symetrical
Explanation:
Attitudes are ________
a. innate
b. generally positive
c. learned
d. unchangeable
Name the two main compounds that are exhaled (breathed out) by humans as a result of Aerobic Cellular Respiration
Answer:
carbon dioxide and oxygen
Explanation:
Carbon dioxide is the waste product of cellular respiration that you breathe out each time you breathe. Blood picks up oxygen and releases carbon dioxide in the lungs. The opposite takes place in the cells where the blood releases oxygen and picks up carbon dioxide.
After synapsis, chromosomes may swap segments in a process called translocation.
True
False
Answer:
false
Explanation:
During synapsis, chromatids of homologous chromosomes exchange segments in a process called crossing over. This rearranges genetic info. As this phase continues the chromosomes coil tightly and a spindle forms.
A population of 1,000 healthy, at risk people is monitored for one year starting on January 1st, and the development of cases of chicken pox is noted. No one has chicken pox at the start of the investigation. Twenty people develop chicken pox on June 30th and forty people develop chicken pox on September 30th. Twenty-four people were lost to follow-up on March 31st, and twenty-four people were lost to follow-up on November 30th. None of those lost to follow-up had developed chicken pox prior to becoming lost. Assume that you can get chicken pox only once.
Required:
What is the cumulative incidence of chicken pox in this population during the one-year period from January 1st through December 31st?
Answer:
[tex]\mathbf{cummulative \ incidence = \dfrac{60}{1000}}[/tex]
Explanation:
We recognize that total occurrence equals new cases of disease over time divided by the number of people at risk at the onset.
Mathematically:
[tex]\mathbf{cummulative \ incidence = \dfrac{New \ cases \ of \ disease \ occurrence}{Number \ of \ population \ at \ risk \ at \ onset}}[/tex]
Given that:
Number of the population at risk = 1000 individuals
New cases during Jan 1 - Dec 31 = 60 because;
At 20 occurred on June 30 & 40 on Sept. 30) & no new cases were identified after that:
∴
[tex]\mathbf{cummulative \ incidence = \dfrac{60}{1000}}[/tex]
Use the following list of organisms to create a food chain diagram.
•Hawk
•Toad
•Green plants
•Snake
Be sure to include the original source of energy for all living things in your diagram. Then, label each of the following: producer, primary consumer, secondary consumer, tertiary consumer.
Answer
green plants eaten by toad toad eaten by snake and snake eaten by hawk
green plants producer
toad primary consumer
snake secondary consumer
hawk tertiary consumer
Explanation:
Answer:
PRODUCER. > Green plants.
PRIMARY CONSUMER > Toad.
SECONDARY CONSUMER > Snake.
TERTIARY CONSUMER > Hawk.
???????????????,,,??,???? What is the answer to number 4 and 5
Answer:
Questions 4-snow and 5 is rain showers
Which fact supports the conclusion that goats are crucial to the international food supply?
Americans use milk from goats to make cheese.
Most of the world’s milk comes from goats.
The flavor of a goat’s milk varies by its breed.
Many Americans prefer cow meat to goat meat.
Answer:
blanks
Explanation:
Answer:most of the world’s milk comes from goats
Explanation:
what observations can be made and what can be concluded from these observations
Answer:
Correct option is A0 Based on the dispersion of white light into its constituent colours, we can conclude that (a) the white light consists of seven colours
Correct option isA0Based on the dispersion of white light into its constituent colours, we can conclude that (a) the white light consists of seven colours(b) the violet light suffers maximum deviation and the red light suffers minimum deviation.
Based on observations from dispersion, it can be concluded that white light is composed of seven colours of light.
What is dispersion of light?Dispersion of light is the separation of white light onto its constituent color as it passes through a refraction prism.
White Light consists of seven colours of varying wavelength.
When light is passed through a refracting prisms, dues the difference in the speed of the different constituents of light, seven colours of light are produced.
Therefore, based on observations from dispersion, it can be concluded that white light is composed of seven colours of light.
Learn more about dispersion of light at: https://brainly.com/question/20259452
Explain why conflict avoidance does not help in sustaining positive relationship
Answer:
Avoidance is not healthy for sustaining the positive relationships as the ignorance or avoidance can cause the damage between the relationships of the people. The maintenance of the relationship among people can be hampered by avoidance. It can make the other people feel neglected. That can cause a failed relationship.
Explanation:
hello I am Iron-60 , the twin of Iron-56, how am different than my twin?
What is this tiny bird doing in this big guy's mouth? The plover bird is
picking the chunks of meat out of the crocodile's teeth. This helps the
crocodile's mouth stay healthy and be ready for its next big meal. What is
type of relationship is being described?
g It was noted in the Experimental Pathways feature in Section 10.4 that at least two- thirds of the human genome is derived from transposable elements. The actual number could be much higher, but it is impossible to make a determination about the origin of many other sequences. Why do you suppose it is difficult to make assignments about the origin of many of the sequences in the human genome
Answer:
TEs are repetitive and mobile elements, thereby it is hard to trace their origins
Explanation:
Repetitive elements are patterns of nucleotide sequences in the DNA characterized to have multiple copies throughout the genome. DNA mini-satellite and Transposable Elements (TEs) are some examples of highly repetitive DNA. TEs are repetitive mobile elements that have the ability to jump within the genome and occupy a major part of eukaryotic genomes. For instance, there is a type of TEs called retrotransposons which mobilize through a copy-and-paste mechanism, thus increasing their number in a genome. In consequence, TEs represent highly repetitive and dynamic genomic sequences, and thereby it is hard to trace their evolutionary histories.
Place these events in the correct order of occurrence in the muscle contraction: End plate potential triggers an action potential Transverse tubules convey action potentials into the interior of the muscle fiber Acetylcholine binds to receptors on the motor end plate Calcium is released from the sarcoplasmic reticulum Ligand-gated channels open leading to depolarization Calcium ions bind to troponin, which then moves tropomyosin
Answer:
1. Acetylcholine binds to receptors on the motor end plate
2. Ligand-gated channels open leading to depolarization
3. End plate potential triggers an action potential
4. Transverse tubules convey action potentials into the interior of the muscle fiber
5. Calcium is released from the sarcoplasmic reticulum
6. Calcium ions bind to troponin, which then moves tropomyosin
Explanation:
Acetylcholine (ACh) is a signaling molecule (neurotransmitter) that binds to receptors on muscle cells. This binding triggers the opening of ligand-gated sodium channels, thereby ions enter into muscle cells, which causes the depolarization of the sarcolemma and thus promotes the release of Ca2+ ions from the sarcoplasmic reticulum. The myoneural junction, also known as the motor endplate, is the site of synaptic contact between a motor axon and a skeletal muscle fiber. The endplate potential is the voltage that produces the depolarization of muscle fibers when ACh molecules bind to their receptors in the cell membrane. This depolarization spreads in the sarcolemma through transverse tubules (T tubules) and thus generates an action potential. Finally, this action potential induces the release of Ca2+ in the sarcoplasmic reticulum, which activates troponin protein and induces muscle contraction.
Name three benefits of keeping plants at home.
Answer:
Studies have shown that indoor plants...
Boost your mood, productivity, concentration and creativity.
Reduce your stress, fatigue, sore throats and colds.
Help clean indoor air by absorbing toxins, increasing humidity & producing oxygen.
Add life to a sterile space, give privacy and reduce noise levels.
the amount of electrical energy that can be generated by a hydroelectric power plants depends upon
Answer:
The amount of electricity a hydropower plant produces depends on two factors: How Far the Water Falls. The farther the water falls, the more power it has. Generally, the distance that the water falls depends on the size of the dam.
Explanation:
The amount of electrical energy that can be generated by a hydroelectric power plant depends upon the following factors:
The actual flow rate of water. The height of the water that falls. What is a Hydroelectric power plant?A Hydroelectric power plant may be defined as a renewable source of energy that generates electricity through the utilization of water from dams or diversion structures. Such types of plants are mainly used to transform hydraulic potential energy into electrical energy from water.
The actual flow rate and height of the water from it is falling demonstrate the amount of generated electrical energy. If the amount of water is present in excess quantity with a huge rate of flow and more the height of water in the hydroelectric power plant, it reveals that the generated electricity must be high under such circumstances.
Therefore, the rate of flow and height of water overall reveals the amount of electrical energy that can be generated by a hydroelectric power plant.
To learn more about Hydroelectric power plants, refer to the link:
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Please help me name each letter and match it to the definition.
Answer:
1. B. Medulla oblongata contains cardiac, respiratory, vasomotor and reflex centers.
2. A. Hypothalamus is the major regulator of ANS
3. D. Occipital lobe is the location of visual cortex.
4. F. Sensory areas are primary site responsible for perceiving cutaneous sensory sensations and proprioception.
5. E.Motor areas directs conscious motor movement
6. C. Cerebellum - coordinates movement by comparing intended movement with actual movement.
7. K. Corpus callosum allows communication between right & left cerebral hemispheres.
8. J. Frontal Lobe - Cognition, personality.
9. A. Hypothalamus - Contains hunger, thirst and thermoregulatory centers.
When cells break down food glucose molecules during cellular respiration, energy is
Answer:
when cells break down food molecules, some of the energy on the molecules is released as heat. Cells use much of the remaining energy to make ATP. When glucose is broken down during cellular respiration energy is stored temporarily in molecules of ATP.
Explanation:
A scientist at a nuclear power plant spills toxic chemicals on her hand. The chemical exposure results in a mutation to the DNA within her skin cells. which of the following is the most likely result of the mutation to the scientist’s skin cells?
A. The damaged DNA spreads to every cell in the body
B. The size of the scientist’s skin cells decreases
C. The scientist’s offspring inherit the mutation from the affected cells
D. The sequence of amino acids with the affected cells is altered
Answer:
Explanation:
the answer is c
Look at the following equation.
Na C02(s) + 2 HCl(aq) + 2 NaCl(aq) + CO2(g) + H2O(1)
What do the symbols in the equation mean?
(s) =
(aq) =
(g) =
(I) =
Creating a checklist of activities is not a helpful strategy for determining what to study for an upcoming test. Please select the best answer from the choices provided T F
Answer:
ture
Explanation:
Answer:
true
Explanation:
edge 2021
In Drosophila, red eyes is wild-type and purple eyes are mutant. Full-size wings are wild-type and vestigial wings are mutant. Flies with wild-type pr pr vg vg genotypes were crossed with double mutant flies with a pr-pr- vg-vg- genotypes. The F1 flies had pr pr- vg vg- genotypes. The F1 flies with heterozygous genotypes were crossed with double mutant flies with a pr-pr- vg-vg- genotypes One thousand offspring were typed. This cross produced 430 red-eye, wild-type wing flies, 65 purple-eye wild-type wing flies, 60 red-eye, vestigial wing flies, and 445 purple-eye, vestigial wing flies. What is the distance between the loci for purple eyes and vestigial wings in centiMorgans (map units)
Answer:
Distance between genes → 12.5 MU = 12.5 cM.
Explanation:
Due to technical problems, you will find the complete explanation in the attached files.
Which of these best predicts the length of time a star "lives" on the Main-sequence and the path it follows as it evolves over time?
its mass
its color
its name
its location
Answer:
its mass is the answer I just look up some research
Visit the link below and use the information to answer the following question.
Ecological Succession: Transformation of Communities over Time
Why does secondary succession occur faster than primary succession?
Answer:
Because there is already presence of soil and nutrients in secondary succession
Explanation:
Ecological succession, which is the series of gradual change that occurs in a community over time, can be of two forms namely: primary succession and secondary succession.
- Primary succession is a kind of succession that occurs in a barren land where no form of life has existed before while secondary succession occurs on a land that has been previously colonized by certain organisms called PIONEER SPECIES, and hence, a substrate containing nutrients called SOIL for growth is available during secondary succession.
This accounts for the reason the secondary succession is faster than the primary succession because there is already presence of soil and nutrients in secondary succession.
Answer:
Soil with nutrients is already present. Seeds are present from earlier occupants, brought in by wind, and/or germinate after fire.
Explanation:
Edge 2021
What do you already know about the rotation and the revolution of the Earth?
Explain your Answer
Answer:
I already know that the earth rotates on its axis because of magnetic forces. I also know that the earth revolves around the sun because of the pull of the sun's gravity.
CAN FISH SURVIVE ONLY IN WATER WITH DISSOLVED OXYGEN?
Answer:
Oxygen dissolves into water from two sources: the atmosphere and from plants in the water. kills fish from oxygen depletions can range from “partial” to “total”. In a partial kill the dissolved oxygen level gets low enough to suffocate sensitive species and large fish, but many small fish and hardy species survive.
Explanation:
I hope this helped you
what is the function of phloem?
Take 50 Points
Answer:
[tex]\huge\boxed{Answer\hookleftarrow}[/tex]
⎆ Phloem is the structural part of the plant that helps in the transportation of food materials from the green parts of the plants (leaves ⇻ where the food is made) to different parts of the plants.
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PLEASE HELP ASAP ILL GIVE YOU BRAINLIEST AND MOST HELPFUL!!
Answer:
the second choice is really the only on that makes sense,
Explanation:
I'm not really sure that plants need rocks but it can't be the third answer choice because soil is made up of cells and microorganisms. Plants can photosynthesize but animals (the mocking jay) cannot. and for the last choice water and sunlight aren't any type of organism, they are abiotic.
I need help with this
Answer:
D
Explanation:
I graphed it
The radius is also 5 therefor it must =25