Explanation:
Introduction
Plants have evolved different reproductive strategies for the continuation of their species. Some plants reproduce sexually while others reproduce asexually, in contrast to animal species, which rely almost exclusively on sexual reproduction. Plant sexual reproduction usually depends on pollinating agents, while asexual reproduction is independent of these agents. Flowers are often the showiest or most strongly-scented part of plants. With their bright colors, fragrances, and interesting shapes and sizes, flowers attract insects, birds, and animals to serve their pollination needs. Other plants pollinate via wind or water; still others self-pollinate.
Asexual Reproduction
Vegetative reproduction is a type of asexual reproduction. Other terms that apply are vegetative propagation, clonal growth, or vegetative multiplication. Vegetative growth is enlargement of the individual plant, while vegetative reproduction is any process that results in new plant “individuals” without production of seeds or spores. It is both a natural process in many, many species as well as a process utilized or encouraged by horticulturists and farmers to obtain quantities of economically-valuable plants. In this respect, it is a form of cloning that has been carried out by humanity for thousands of years and by plants for hundreds of millions of years. Sexual Reproduction and The Flower
The flower is the reproductive organ of plants classified as angiosperms. All plants have the means and corresponding structures for reproducing sexually. The basic function of a flower is to produce seeds through sexual reproduction. Seeds are the next generation, serving as the primary method in most plants by which individuals of the species are dispersed across the landscape. Actual dispersal is, in most species, a function of the fruit (a structural part that typically surrounds the seed).
image
Plants and sexual reproduction: Plants that reproduce sexually often achieve fertilization with the help of pollinators such as (a) bees, (b) birds, and (c) butterflies.
Sexual Reproduction in Gymnosperms
Gymnosperms produce both male and female gametophytes on separate cones and rely on wind for pollination.
image
Male and female gametophytes: These series of micrographs shows male and female gymnosperm gametophytes. (a) This male cone, shown in cross section, has approximately 20 microsporophylls, each of which produces hundreds of male gametophytes (pollen grains). (b) Pollen grains are visible in this single microsporophyll. (c) This micrograph shows an individual pollen grain. (d) This cross section of a female cone shows portions of about 15 megasporophylls. (e) The ovule can be seen in this single megasporophyll. (f) Within this single ovule are the megaspore mother cell (MMC), micropyle, and a pollen grain.
Female Gametophyte
The female cone also has a central axis on which bracts known as megasporophylls are present. In the female cone, megaspore mother cells are present in the megasporangium. The megaspore mother cell divides by meiosis to produce four haploid megaspores. One of the megaspores divides to form the multicellular female gametophyte, while the others divide to form the rest of the structure. The female gametophyte is contained within a structure called the archegonium.
Reproductive Process
Upon landing on the female cone, the tube cell of the pollen forms the pollen tube, through which the generative cell migrates towards the female gametophyte through the micropyle. It takes approximately one year for the pollen tube to grow and migrate towards the female gametophyte. The male gametophyte containing the generative cell splits into two sperm nuclei, one of which fuses with the egg, while the other degenerates. After fertilization of the egg, the diploid zygote is formed, which divides by mitosis to form the embryo. The scales of the cones are closed during development of the seed. The seed is covered by a seed coat, which is derived from the female sporophyte. Seed development takes another one to two years. Once the seed is ready to be dispersed, the bracts of the female cones open to allow the dispersal of seed; no fruit formation takes place because gymnosperm seeds have no covering.
plants experience _______ gravitropism when their stems move upward.
A. positive
B. negative
Answer:
Negative
Explanation:
Gravitropisms. Phototropism is a response to the stimulus of light, whereas gravitropism (also called geotropism) is a response to the stimulus of gravity . When the stem grows against the force of gravity (upwards), this is known as a negative gravitropism.
Answer:
negative
Explanation:
this is because negative gravitropism is when a plant grows away from gravity (like moving upwards). then, positive gravitropism is when the roots of a plant move grow downwards.
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High cholesterol and triglycerides may indicate cardiovascular disease. What happens when cholesterol and other lipids are deposited in artery walls?
Answer:
With high cholesterol, you can develop fatty deposits in your blood vessels. Eventually, these deposits grow, making it difficult for enough blood to flow through your arteries. Sometimes, those deposits can break suddenly and form a clot that causes a heart attack or stroke.
1. What is the overall reaction for photosynthesis?
Explanation:
helps grow the plant to become to its fulfilled size
Scottish Highland cattle, which have long hair, are suited for cold, damp climates of the Scottish isles. On the other hand, Brahman cattle, which have short hair, are suited for a warmer climate. This comparison is an example of:
A. adaption
B. taxonomy
C. polyploidy
D.punctuated equilibrium
Describe the ways mutations can affect DNA and chromosomes.
The mutation affects DNA and chromosomes by changes in the sequence of DNA or changes in the gene present on the chromosome.
What is mutation?The mutation is a sudden change in the structure of chromosomes or DNA. The smaller mutation affects the nucleotide base in DNA, while the larger mutation affects the genes present on the chromosomes.
The substance which causes mutation is known as mutagens. Mutation can cause problems in growth and development and affects the functioning of the body. When changes occur in chromosomes or DNA, they cause changes in the protein. Due to this, a different kind of protein is produced.
The mutation is caused by the insertion, duplication, deletion, and substitutions of a DNA sequence. Thus, mutation can affect DNA and chromosome in many ways.
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Please help me! 10 POINTS!
Answer:
both mass and velocity will increase
Explain how scientists use geologic time to determine the age of landforms.
geologic time use the layer of Rock to describe relationship of events and their sequence chronological order over the history of Earth the layering is a result of the buildingup tiny beats of rocks sediments or Lava cooling at the surface of many years think think of it like a stock of pancakes-the bottom layer is the one that was placed first and therefore is the oldest. the sediments that create the layer of the earth as said one or top of the other
Question 7 (1 point)
How are humans changing the carbon der
Lesson 1.10
all of the choices
Answer:
Human activities affect the carbon cycle through emissions of carbon dioxide (sources) and removal of carbon dioxide (sinks). The carbon cycle can be affected when carbon dioxide is either released into the atmosphere or removed from the atmosphere.
Explanation:
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CALLING ALL BOYS I NEED UR HELP.
Whats an Allele? Plz
Contrast the terms “parasitism” and “mutualism” in a sentence
Answer:
Explanation:
Mutualism is the interaction between two or more organisms where both organisms can benefit from the interaction while Parasitism is the interaction between two species where only one benefits from the other organism and the other is harmed in return
Answer:
When both the partners or organisms get benefits from one another by living together is known mutualism. When only one partner or organism gets benefits without any effect on the other is commensalism. When one partner or organism gets benefits while the other is harmed is known as parasitism.
what do the phase changes condensation, evaporation, and crystallization have in common?
Answer:
They are all a part of the water cycle.
Explanation:
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Thermostats transform thermal energy into mechanical energy.
True or false
Answer:
False
Explanation:
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How can maintaining water resources promote a healthy ecosystem ? For APA report make it a long response pls
Answer: The main function of water is to propel plant growth; provide a permanent dwelling for species that live within it, or provide a temporary home or breeding ground for multiple amphibians, insects and other water-birthed organisms; and to provide the nutrients and minerals necessary to sustain physical life.
Explanation:
Dr. Wicked administers a toxin that causes a synthesized protein to be improperly packaged and incorrectly delivered to the wrong destination by this cell.
Which labeled structure is the most likely target of the toxin causing this issue in the cell?
Choose 1 answer:
Choose 1 answer:
(Choice A)
A
Structure A
(Choice B)
B
Structure B
(Choice C)
C
Structure C
(Choice D)
D
None of these labeled structures would be a target of this toxin.
which statement correctly describes greenhouse gases in the atmosphere?
Answer: It is a process by which greenhouse gases allow the sun’s light to penetrate the atmosphere but stop the heat from escaping.
Explanation:
Greenhouse effect is the natural heating of the Earth's surface due to the fact that the sunligth waves may penetrate the atmosphere and reach the solid surface, but when the sunlight waves return after reaching the solid surface, process that changes the wavelength of the sunlight, they cannot penetrate the greenhouse gases and so the heat is kept inside the atmosphere with the consequent increase of temperature.
In cats, the allele for black coat color is dominant over the allele for white coat color. If a white cat crossed with a heterozygous cat, what is the expected genotypic ratio? *
10 points
4BB : 0Bb : 0bb
2BB : 2Bb: 0bb
0BB : 2Bb: 2bb
0BB: 0Bb: 4bb
HELP!
In the desert, saguaro cacti, owls, horned lizards, and fire ants all share the same space.
Which example can be considered a population?
the lizards and the ants
all plants in the same area
all species in the same area
all saguaro in the same area
Answer:
I did the test; proof
2. Wolves have genes that give them a very powerful sense of smell much more
powerful than humans, this is an adaptation by natural selection. The wolves that
reproduced more offspring with a better sense of smell thereby increasing the
frequency of those genes in the population that survived longer. Give an example of
adaptations in other organisms that may have resulted from variations that were
favored by natural selection.
Answer:
A good example may be represented by different shapes and sizes of beaks in finches living on different Galapagos islands
Explanation:
According to the evolutionary theory proposed by Darwin, natural selection is a mechanism that acts on heritable phenotypic variation among individuals within a population. Genetic variation can be considered as the primary source of heritable phenotypic variation. Those organisms that are better adapted for a particular environment will have more chances to survive and reproduce, thereby passing these heritable traits to the next generation. For example, during his work, Darwin observed that the shape and size of beaks in finch species from different islands in the Galapagos archipelago varied as a consequence, i.e., as an adaptation, to the availability of food resources present in each island.
An example of adaptations in other organisms that may have resulted from variations that were favored by natural selection. - The light-colored mice are an adaption favored by natural selection as they were able to live longer.
Adaptations are physical or behavioral traits that make an organism better suited to its environment. The inheritable variation comes from random mutations.
the example of such variations caused by natural selection are:
The Deer mouse adapted to the environment by developing a lighter color.The light-colored mice were able to live longer.Thus, The light-colored mice are an adaption favored by natural selection as they were able to live longer.
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are proteins that are found on the surface of some red blood cells,
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What is an adaptation?
A change that prevents a species from surviving.
A change that helps a species survive.
A change that makes a species become extinct.
A change that makes a species prettier to look at.
Answer:
the second one
Explanation:
In the system used to classify all organisms, which of the following is true
(A) All groups have the same number of organisms.
(B) Organisms in the same group have similar characteristics.
(C) The largest groups have the most important animals.
(D) Organisms are placed in groups by how big they are.
Answer:
B is correct, Organisms in the same group have similar characteristics
Explanation:
HELP SCIENCE PLS ASAAAP
vegetable seeds that do not germinate well after 1 or 2 years are classifed as
Answer:
yes
Explanation:
Photosynthesis
How are the three international conflicts similar and how are they different?
Answer:
what's the question? It is not showing anything expect for "How are the three International conflicts similar and how are they different."
Which of the following might be an adaptation for a predator? AS SOON AS POSSIBLE NEED HELP PLS THX
Answer:
we need the answers
Explanation:
Answer:
Many predators have adaptations that help them survive in the wild. For example, the snake shown below has camoflauge coloring to look like its surroundings. This gives it the element of surprise when going to attack its prey. These adaptations help the predator in hunting for food. Predators have "weapons", or adaptations, that help them hunt and kill prey. Predators' three main "weapons" are teeth, claws, and jaws. The lion below has all 3 of these "weapons" or adaptations that are used for catching its prey. A lion has sharp claws for catching and grabbing hold prey such as a zebra, and strong jaws and teeth for biting and killing the zebra and for ripping off and chewing the meat.
Explanation:
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What happens to the chromosomes when a cell divides to make a copy of itself?
Answer:
the cell copies or replicates its chromosomes and then splits the copied chromosomes equally to make sure each daughter cell has a full set.
Answer:
Mitosis is used to produce daughter cells that are genetically identical to the parent cells. The cell copies or "replicates" it's chromosomes and then splits the copied chromosomes equally to make sure that each. daughter cell has a full set.
Explanation:
I majored in Biology
Neep help!!
1. A primary function of a plant root is to-
O A release carbon dioxide
O B absorb water and minerals
O c digest organic materials
O D produce secondary growth
Answer:
B is thr answer absorb water and minerals
when bacteria make their own food they are called
Answer:
Explanation:
They are called Autotrophs
How do you think that wearing personal protective equipment helps to protect us from contracting airborne diseases?
Answer:
Airborne transmission may occur if patient respiratory activity or medical procedures generate respiratory aerosols. These aerosols contain particles that may travel much longer distances and remain airborne longer, but their infective potential is uncertain. Contact, droplet and airborne transmission are each relevant during airway manoeuvres in infected patients, particularly during tracheal intubation.
Explanation: