Answer:
The modern medical era began when an absent-minded British scientist named Alexander Fleming returned from vacation to find that one of the petri dishes he forgot to put away was covered in a bacteria-killing mold. He had discovered penicillin, the world's first antibiotic.
What has very thin walls to allow the nutrients and gasses to be exchanged between the blood and cells?
ОООО
Arterioles
Venules
Veins
Capillaries
Answer:
Arterioles
Explanation:
Arterioles are considered as the primary resistance vessels as they distribute blood flow into capillary beds. Arterioles provide approximately 80% of the total resistance to blood flow through the body.
Cereal crops - eg simple question free
Answer:
Important cereals are wheat, rice, maize, oat, barley, rye, millet and sorghum.
Answer:
Explanation:
some cereals are wheat, rice, maize, oat, barley, rye, millet and sorghum.
Why does neurones contain many mitochondria and many ribosomes?
Answer:
Neurons depend on mitochondria. ATP generation by mitochondrial respiration in the brain consumes 20% of the body's oxygen although the brain is only 2% of the mass of the body (Attwell and Laughlin, 2001). ... Every part of the neuron requires ATP and therefore requires mitochondria to be present.The dendritic processes and spines of neurons are essentially expansions of cytoplasm containing most of the organelles found in the cell body. ... Rough endoplasmic reticulum and ribosomes are present in large but not small dendrites.
The neurones contain many mitochondria and many ribosomes as neurons depend on mitochondria. ATP generation by mitochondrial respiration in the brain consumes 20% of the body's oxygen although the brain is only 2% of the mass of the body.
What are neurons?The neurones contain many mitochondria and many ribosomes as neurons depend on mitochondria. ATP generation by mitochondrial respiration in the brain consumes 20% of the body's oxygen although the brain is only 2% of the mass of the body.
Every part of the neuron requires ATP and therefore requires mitochondria to be present.The dendritic processes and spines of neurons are essentially expansions of cytoplasm containing most of the organelles found in the cell body. Rough endoplasmic reticulum and ribosomes are present in large but not small dendrites.
The outermost part of brain has been known as Dura mater which has been consist of a strong membrane layering and it has been thick located just beneath the skull and vertebral column.
Therefore, the neurones contain many mitochondria and many ribosomes as neurons depend on mitochondria. ATP generation by mitochondrial respiration in the brain consumes 20% of the body's oxygen although the brain is only 2% of the mass of the body.
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identify the small facial bones found in the medial wall of the orbit.
Answer:
Lacrimal
Explanation:
bone growth in which the bone increases in diameter is called
Appositional growth is the term for the rise in diameter. The periosteum's osteoblasts build compact bone around the exterior bone surface.
How do muscle cells access what they need to keep producing energy
Muscle cells access what they need to continue producing energy through chemical energy from ATP to transform it into mechanical energy.
Muscle cells are elongated cells whose length can reach several centimeters.
The muscle uses ATP (energy) to carry out conformational changes in its molecular structure => variation in the length of the sarcomere.
Adenosine triphosphate (ATP) is the basic source of energy for muscle contraction.
Each link stores 7300 calories of energy per mole of ATP under normal conditions and when a phosphate radical is separated from the molecule, these calories are available providing the energy necessary for muscle contraction.
The muscle cell has three mechanisms to resynthesize ATP:
ATP synthesis through phosphocreatine.
Anaerobic glycolysis process with the transformation of muscle glycogen into lactate.
From oxidative phosphorylation.
ATP synthesis through phosphocreatine consists of the transfer of energy from phosphocreatine to ADP so that it can reincorporate a phosphate group to its molecule and transform it into ATP.
So the energy that has been released in the hydrolysis of PCr is directly used to resynthesize ATP from ADP.
Therefore, we can conclude that muscle cells access what they need to continue producing energy through the chemical energy of ATP to transform it into mechanical energy.
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Hair samples can provide information on all of the following EXCEPT.....
a
Age
b
Gender (sex)
c
Race
d
Hair samples can provide information on all of these.
Answer:
the answer should be A) Age
List the features of the gaseous exchange surface in humans.
Answer:
they give the lungs a really big surface area.
they have moist, thin walls (just one cell thick)
they have a lot of tiny blood vessels called capillaries.
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help help help help help
Answer:
D. There is a warm front coming from the south.
cuál es la fuente de conocimiento de la astrología? la observación de la naturaleza? los libros?
Answer: c
Explanation: trust
1. Give four (4) importance of “wind”?
2. How and when is the sun harmful to plants and animals/humans?
3. Why do you think the son is very important to plants?
4. Explain or give the importance of the sun in relation with the weather of any place on planet earth?
Answer:
1. Wind is an important element when it comes to current weather and predicting future forecasts. Wind transports moisture and temperature from one area to another, therefore weather conditions change with the shift of wind direction.
2.All plants and animals, including humans, are exposed to the dangers of solar UV radiation; it can cause significant damage to plants, as seen in crop yield reduction and leaf burn, and can damage animal skin health.
3.sun-light is a key energy source for all plants. Through a process called photosynthesis, plants absorb energy from the sun, which fuels the processes necessary for survival.
4.The Sun warms our planet, heating the surface, the oceans and the atmosphere. This energy to the atmosphere is one of the primary drivers our weather. Our climate is also strongly affected by the amount of solar radiation received at Earth.
Explanation:
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testosterone, a lipid-soluble signaling molecule, crosses the membranes of cells throughout the body but affects only target cells because __________.
Answer:
of intracellular receptors
Explanation:
this should be correct
1. describe the stages of the cell cycle
2. use a model to illustrate the role of cellular division in the formation of new cells
3. describe the structure of a chromosome
4. follow chromosomes through the processes of mitosis and cytokinesis
Answer:
1.The cell cycle, or cell-division cycle, is the series of events that take place in a cell that cause it to divide into two daughter cells.
2. In the Picture Linked.
3. Chromosome help ensure that DNA is replicated and distributed appropriately during cell division. Each chromosome has a centromere, which divides the chromosome into two sections – the p (short) arm and the q (long) arm.
4. Mitosis occurs at the sites of growth and development of new tissues. Here are the stage of mitosis Below:
Prophase
This is the initial phase. The chromosomes in the nucleus become visible as thin coiled threads. In animals, the centrosome found in the cytoplasm divides to form two centrioles. The chromosomes become tightly coiled and shorter. From each centriole, fine fibers develop and elongate to form spindle apparatus. The nucleolus becomes dispersed in the nucleus and disappears. The nuclear membrane also break and disappears.
Metaphase
The pairs of chromatids align along the equator of the spindle apparatus and are attached to it at their centromeres.
Anaphase
The centromere of each chromosome splits and the chromatids separate. Each chromatid moves to the opposite poles of the cell. The chromatids appear as V--shaped.
Telophase
The spindle fibers disintegrate and disappear. New nuclear membrane forma around each set of chromatids. A nucleolus develops in the nucleus of each daughter cell. The cytoplasm now divides in a process called cytokinesis. In animals, an invagination develops at the plasmalemma near the equator of the cell.
Relationship between mitosis and cytokinesis:
Mitosis is the division of a nucleus. Cytokinesis is the division of the cytoplasm. If mitosis occurred without cytokinesis, the cell would contain two nuclei and twice the DNA. If cytokinesis occurred without mitosis , one of the new cells would lack DNA and a nucleus altogether.
Give an example of a 1) solid, 2) liquid and 3 gas.
1) Rock
2.) Acid
3.) Helium
I hope this is what you wanted
1. Brick
2. Water
3. Lava
Identify one
food chain in
this food
web.
Answer:
Duckweed, Duck, Fox
Explanation:
Any combination that starts with a producer and ends in a consumer in order of consumption.
Other examples are :
Algae, water snail, duck, fox
questions.
Questions
1 a Name the microorganism which causes the disease smallpox.
Answer: Variola Virus
Explanation:
15 POINTS!!!! At a molecular level, does plasma have more or less energy than other states of matter?
Answer: Hello!
Plasma is more energetic than other states of matter.
Explaination:
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a biology teacher shows the class pictures taken while using different microscopes. the plant cells have visible chloroplasts, and a sample of human cheek cells shows a nucleus and a cell membrane. what type of microscope was used for these pictures?
If a biology teacher shows the class pictures where plant cells have visible chloroplasts human cheek cells show a nucleus and a cell membrane. then the type of microscope that was used is an optical microscope.
What is an optical microscope?An optical microscope is a device that contains different magnification lens that allows for increasing the size of the image. These lens include ocular and objective lens.
In conclusion, an optical microscope can be used to observe microscopic substructures such as chloroplasts in plant cells or the cell nucleus in human cells, which depend on the magnification of the image (cell nucleus: 1000 X).
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nerve fibers scattered throughout the dermis are associated with
Answer:
muscles, glands, and sensory receptors
Explanation:
The dermis is composed largely of: dense irregular connective tissue. Nerve fibers scattered throughout the dermis are associated with: muscles, glands, and sensory receptors. Which of the following is not correct concerning the skin? The subcutaneous layer is between the dermis and the epidermis.
which structures are found in palisade cells and liver cells
Answer:
All cells contain a nucleus and a nuclear envelope and the liver cell is no exception. It has exactly the same control over the cell as the palisade nucleus does. To keep it all together, it is surrounded by a cell membrane.
Explanation:
Since a liver cell is an animal cell, it lacks chloroplast. Below the epidermis of the leaves is a palisade cell. It participates actively in photosynthesis, chloroplasts are present.
What structures are found in liver cells?Liver cells lack a cell wall but do have a nucleus and a cell membrane. It receives blood from two main sources: The Hepatic Portal Vein, which delivers blood from the digestive tract that is nutrient-rich.
The nucleus and nuclear envelope are components of every cell, including liver cells. The cell is under the exact same management that the palisade nucleus is. It is encased in a cell membrane, which serves to keep everything together.
Therefore, as an animal cell, the liver lacks the cell wall, chloroplast, and big vacuole that are often seen in plant cells.
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Cell walls are only found in animal cells.
Answer:
False
Explanation:
Animal cells do not have a cell wall
Answer:
i think so yes beacuse i remember it that i read in in science
What are things that sound waves can travel through?
Answer:
Sound waves are longitudinal waves. They need a medium to travel through. They cause particles of the medium to vibrate parallel to the direction of wave travel. The vibrations can travel through Solids, Liquids or Gases.
Explanation:
Hope it helps
which of the following is an artificial
hormone
PAA
IBA
NAA
ALL OF THESE
pls...help Mee with the correct answer
What is the most venomous snake in the world? Please help ASAP! Help would be appreciated. I will give Brainliest!
Note: it's my homework! :)
The most venomous snake in the world is Inland Taipan.
Answer: Oxyuranus microlepidotus, also called the fierce snake
Explanation: The snake with the most deadly venom.
NOT MY WORK I FOUND IT ON https://www.britannica.com/list/9-of-the-worlds-deadliest-snakes
4. Which statement best expresses a basic scientific
assumption?
A Interpretation of experimental results has
provided explanations for all natural phenomena.
B) Ifa conclusion is valid, similar investigations by
other scientists should result in the same
conclusion.
C) For any conclusion to be valid, the design of the
experiment requires that only two groups be
compared
D) After a scientist formulates a conclusion based
on an experiment, no further investigation is
necessary
3
Answer:
Choose B) B) If conclusion is valid, similar investigations by
other scientists should result in the same
conclusion.
Explanation:
Which s an example of why the process of photosynthesis is important to life on Earth?
Explanation:
Thanks to photosynthesis, us and many other animals can have oxygen! That's because when plants photosynthesize, they take in carbon dioxide, and the waste is oxygen, which a lot of things need to survive.
Describe how the structure of an atom determines it's function. How is the structure of
an atom related to the properties A displays when bonding or reacting with other
atomslelements. Provide a simple example,
Answer:
Atoms consist of three basic particles: protons, electrons, and neutrons. The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain electrons (negatively charged).
Explanation:
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what organelle is critical for endocytosis and exocytosis to occur
Answer:
Endoplasmic Reticulum
Explanation:
The cell membrane, also known as the plasma membrane, is an organelle that is essential for both endocytosis and exocytosis to take place.
Thus, The cell membrane, which encloses the cell and separates its internal contents from the outside environment, is a barrier that is selectively permeable.
The process by which cells absorb materials from their surroundings is known as endocytosis. The cell membrane invaginates and creates a vesicle that encloses the substance being transported into the cell during endocytosis.
The vesicle is subsequently taken inside and moved into the cytoplasm of the cell. In this process, the cell membrane is essential because it helps the endocytic vesicle develop.
Thus, The cell membrane, also known as the plasma membrane, is an organelle that is essential for both endocytosis and exocytosis to take place.
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nuclear envelope reappears
spindle dissolves
chromosomes uncoil
These processes occur during
telophase.
prophase.
anaphase.
metaphase.
Answer:
D). Telophase
Explanation:
in what situation can a harmful deletion in a chromosome persist in a population?
Answer:
If the homologous chromosome lacks the deletion