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Describe the structure of blastula

Blastulation is the process of formation of the hollow and multicellular blastocyst. The process of blastulation can be summarized as follows: The embryo (blastocyst) that enters the uterus remains floating in uterine cavity for 2-4 days after its entry i.e. till the end of 7th day after fertilization Blastula, hollow sphere of cells, or blastomeres, produced during the development of an embryo by repeated cleavage of a fertilized egg. The cells of the blastula form an epithelial (covering) layer, called the blastoderm, enclosing a fluid-filled cavity, the blastocoel The blastula is usually a spherical layer of cells (the blastoderm) surrounding a fluid-filled or yolk-filled cavity (the blastocoel). Mammals at this stage form a structure called the blastocyst, characterized by an inner cell mass that is distinct from the surrounding blastula, shown in Figure 1b The typical blastula is a ball of cells. The next stage in embryonic development is the formation of the body plan. The cells in the blastula rearrange themselves spatially to form three layers of cells in a process known as gastrulation. During gastrulation, the blastula folds upon itself to form the three layers of cells The blastula is made up of a hollow spherical layer of cells, referred to as the blastoderm which surrounds a yolk or fluid-filled space called the blastocele or blastocoel. In most mammals,..

After about seven cell divisions, the embryo has become a blastula consisting of at least 128 cells. If you were to look inside the blastula, you would see that most of it is empty space. This.. (Greek, blastos = sprout + cystos = cavity) or blastula, the term used to describe the hollow cellular mass that forms in early development. The blastocyst consists of cells forming an outer trophectoderm (TE, trophoblast) layer, an inner cell mass (ICM, embryo blast) and a blastocoel (fluid-filled cavity) Describe the formation of a blastula in sea urchin, amphibian, and bird embryos. Distinguish among meroblastic cleavage, holoblastic cleavage, and the formation of the blastoderm. Named to distinguish them from the adaptive origin of the original structure. Define exaptation and illustrate this concept with an example Explain the steps of parturition. 3. Explain the histological structure of testis. 4. Describe the structure of blastula. 5. Explain the histological structure of ovary in human. 6. Describe the various methods of birth control to avoid pregnancy

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The mouth opening appears at their middle which absorbs the neighbouring cells. This stage of the blastula is known as stomoblastula. The blastula-un­dergoes inversion and the flagellated cells are brought outside. The embryo at this stage is known as amhiblastula (Fig 19.7F). This is a typical calcareous larva The blastula (from Greek βλαστός (blastos meaning sprout) is a hollow sphere of cells (blastomeres) surrounding an inner fluid-filled cavity (the blastocoel). Embryonic development begins with a sperm fertilizing an egg cell to become a zygote, which undergoes many cleavages to develop into a ball of cells called a morula The blastocyst is a structure formed in the early development of mammals. It possesses an inner cell mass (ICM) which subsequently forms the embryo. The outer layer of the blastocyst consists of cells collectively called the trophoblast. This layer surrounds the inner cell mass and a fluid-filled cavity known as the blastocoel Describe how you were able to tell by observation when a sea urchin egg was fertilized. 3. Use the key choices to identify the embryonic stage or process described below. Key: a. cleavage c. zygote e. blastula b. morula d. fertilization f. gastrulation 1. fusion of male and female pronuclei 2. solid ball of embryonic cell The term implantation is used to describe process of attachment and invasion of the uterus endometrium by the blastocyst (conceptus) in placental animals. In humans, this process begins at the end of week 1, with most successful human pregnancies the conceptus implants 8 to 10 days after ovulation, and early pregnancy loss increases with later implantation

By the nextday, continued cleavage has produced a hollow ball of thousands of cells called the blastula. A fluid-filled cavity, the blastocoel, forms within it. During this entire process there has been no growth of the embryo Development Step 2: Cleavage and Blastula Stage. After fertilization successfully activates the egg, the egg begins a series of rapid cell divisions called cleavage, illustrated below.Typical cell division occurs every 18-24 hours, but cleavage cell divisions can occur as frequently as every 10 minutes The blastula is usually a spherical layer of cells (the blastoderm) surrounding a fluid-filled or yolk-filled cavity (the blastocoel). Mammals at this stage form a structure called the blastocyst, characterized by an inner cell mass that is distinct from the surrounding blastula, shown in Figure 24.24 b. During cleavage, the cells divide. Blastula stage; Information: After the morula stage the blastomeres spread and build a monolayer of cells around a central cavity (the blastocoel, bc). This stage is called the blastula stage (blastula = vesivle). The fertilization membrane is degraded by enzymes and disappears. The epithelium of the cells of the vegetal pole (vp) becomes.

The Blastula is a spherical, hollow, one celled thick structure, found during the first stage of embryogenesis, and is known as the 'pre-embryo'. The gastrula is formed during the gastrulation stage of embryogenesis, and consists of three germ layers, with the structure known as the 'mature-embryo' When the sperm and egg combine, they form a zygote. As the days and hours progress, the zygote starts multiplying its cells until eventually it is a bundle of many cells. This then rearranges..

Name and describe the 5 vertebrate classes (within Superclass Gnathostomata) relative to the following: 1) skeleton and jaw composition 2) number & structure of paired appendages 3) dermal covering over body 4) relative number of gill slits of an adult 5) type of covering over egg 6) number of heart chamber Blastula: Transferring of blastulas results in a lower pregnancy rate compared to that of morula. Conclusion. Morula and blastula are two early stages of embryonic development in animals. The main difference between morula and blastula is in their structure. Morula is a solid cell mass, which develops from the zygote due to rapid mitotic cleavages Blastula consists of a spherical cell layer known as the blastoderm. The blastoderm surrounds the fluid-filled cavity known as blastocoel. The blastula in mammals develops into the blastocyst. Blastocyst contains an inner cell mass (ICM), which is distinct from the blastula

Blastula biology Britannic

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The blastula is usually a spherical layer of cells (the blastoderm) surrounding a fluid-filled or yolk-filled cavity (the blastocoel). Mammals at this stage form a structure called the blastocyst, characterized by an inner cell mass that is distinct from the surrounding blastula, shown in Figure 2b Cell Division - Mitosis - in Whitefish Blastula Cells: The arrow (A) points to a cell nearing the end of telophase. During telophase the spindle is disassembled and the nuclear envelope reforms around the divided sets of chromosomes Starfish blastula and gastrula w.m. (We have two versions of this slide: w.m. means whole mount, with the whole embryo placed on the slide. Sec. means that the slide contains sections, or slices, of the embryos. Both slides are worth looking at, but the w.m. version is better.) Animals and plants develop differentl Process involving cell rearrangements to form the three primary germ layers. gastrulation. 8. Embryonic stage in which the embryo consists of a hollow ball of cells. blastula. 9. What is the importance of cleavage in embryonic development? It provides a large number of smaller cells for morphogenesis. 10 structure. It is called the morula stage, as this has superficial resemblance to a mulberry fruit. Morula stage gives rise to a stage called the blastula which is a hollow ball like structure. Blastula: At the end of cleavage the solid ball of cells give rise to blastula which consists of number blastomeres

The blastula of frog is called amphiblastian as the cavity is confined to only the animal pole. The veg­etal pole however is composed of a solid mass of non pigmented yolky cells. In the thirty two cell stage, the blastula consists of a single layer of cells and is called the early blastula But blastula is a hollow structure, due to the presence of fluid-filled space called blastocoel. • Trophoblast cells are present in blastula unlike in morula. • Unlike in blastula, morula consists of an inner and outer cell masses. • Duration of the formation of morula is lower than the formation of the blastula

Cleavage and Blastula Stage Biology for Majors I

called a blastula. This process in shown in the diagram below. Zygote Eight-cell stage Blastula cross section (a) The photograph below shows a cell of a blastula of the whitefish, Coregonus, at one stage of mitosis. Magnification ×1000 Put a cross in the box next to the correct word to complete the following statement Cleavage results in a blastula, a ball of cells with a central cavity called the blastocoel. Below are two diagrams of blastulas. On the left is a sea urchin blastula, and on the right is a frog blastula. The pattern of cleavage is influenced by the amount of yolk in the egg. In eggs with less yolk, cleavages are equal, and the resulting.

43.5B: Cleavage, the Blastula Stage, and Gastrulation ..

  1. Bio 160: Lab 5 Name MITOSIS CO Lab 5, Part 1: Mitosis & Cytokinesis OBJECTIVES To observe the stages of mitosis in prepared slides of whitefish blastula and onion root tips To gain a better understanding of the process of mitosis in plant and animal cells Name, identify, and describe the events occurring during the phases of the cell cycle Relate the process of DNA replication to the process.
  2. Describe the structure of alginate. The commercially available alginates are white to cream coloured powders. 1% alginic acid solution gives a pH value of 2.9 while it is 2.3 and 7.5 for 1% solutions of propylene glycol and sodium alginate respectively. Alginic acid is essentially insoluble in cold or hot water, but it does swell quite strongly
  3. however the morula stage gives rise to a stage called the blastula which is a hollow ball like structure. Blastulation At the end of cleavage the solid ball of cells give rise to blastula which consists of a number blastomeres. The characteristic features of the blastula stage are the presence of a well defined cavity called the blastocoel
  4. Late in the blastula stage, groups of cells break free of the animal end of the embryo and position themselves within the blastocoel. These cells. called primary mesenchyme, will form skeletal elements (called spicules) of the embryo. Q.11. Describe the gastrulation and morphogenesis in echinoderms. Ans. Gastrulation. Ans
  5. Structure in humans that is the structural base for the umbilical cord; solid waste disposal in nonplacental animals embedding the blastula to the uterine wall: The fluid filled, hollow ball of cells stage of development is the blastocyst. Describe the composition of semen and name all the structures contributing to its formation
  6. Cleavage and Blastocyst Formation. The product of fertilization is a one-cell embryo with a diploid complement of chromosomes. Over the next few days, the mammalian embryo undergoes a series of cell divisions, ultimately leading to formation of a hollow sphere of cells known as a blastocyst

A fate map is a diagram of an egg or blastula, indicating the fate of each cell or region, at a later stage of development. Fate maps are essential tool in most embryological experiments. They provide researchers with information on which portions of the embryo will normally become which larval or adult structure As the cleavage proceeds, the number of blastomeres increases and cells of blastula are arranged into a hollow ball like structure. The central cavity of blastula is called as blastocoel or segmentation cavity or primary body cavity. Invagination of the cells at one end of the blastula results in the formation of Gastrula Describe what you see. The embryo goes from one little single cell to a bunch of cells together (multi cell). 2. Observe: Click Continue to watch the embryo undergo blastulation. A. Describe what you see. The embryo goes from a bunch of cells together to a cell with cells as the outer circle and a few inside but is mostly hallow on the inside. B

Blastula. Blastula represents the first important stage after the fertilization and plays an important role in the development of organisms. It is a hollow, spherical, one celled thick structure formed by the process called blastulation. Both holoblastic and meroblastic cleavages give rise to blastula Chapter 14. Gastrulation and Neurulation. It is not birth, marriage, or death, but gastrulation , which is truly the most important time in your life. During gastrulation, cell movements result in a massive reorganization of the embryo from a simple spherical ball of cells, the blastula, into a multi-layered organism Describe the three stages of interphase; Each sister chromatid develops a protein structure called a kinetochore in its centromeric region Place a fixed and stained microscope slide of whitefish blastula cross-sections under the scanning objective of a light microscope Blastula stage: The micromeres dives more rapidly than megameres which results in formation of small fluid filled cavity known as Blastocoel or segmentation cavity. Blastocoel bearing stage is called Blastula; The floor of blastocoel is composed of layer of yolk laden megameres while the roof is composed of micromeres Blastula Blastocoel Figure 8.7 Cleavage in the Sea Urchin mesoderm ectoderm. 3 Figure 8.4(2) Summary of the Main Patterns of Cleavage Figure 10.1 Cleavage of a Frog Egg Blastula Figure 10.2 Scanning Electron Micrographs of Cleavage of Frog Egg. 4 I t is not birth, marriage, or death, bu

Formation of Blastula - Medical New

Modern texts describe the formation of the gastrula as the migration of the cells of the blastula into its interior. Clearly, the expansion of the membrane constituting the blastula, constrained as it is by the fixed outer shell of the vitelline membrane, will predictably force cells at the surface to invade the interior of the blastula more. Yes, because implantation begins to occur when the zona pellucida disintegrates, allowing the blastocyst to stick to the endometrium tissue. This happens about one week after fertilization and occurs after cleavage. The video Implantation gives a good overview of the process. Comment on Sofia Hu's post Yes, because implantation. The lower cells of the blastula are endodermal and those of the upper cells are ectodermal. Gastrulation occurs by the invagination of endodermal cells into ectodermal cells to form a cylindrical gastrula with an archenteron cavity. A blastopore narrows to form the mouth. Mesoderm develops from 2 large cells of blastula, called mesoblasts

Morula Stage. An early stage in post-fertilization development when cells have rapidly mitotically divided to produce a solid mass of cells (16 or more) with a mulberry appearance is called the morula stage. The morula stage is the final stage prior to the formation of a fluid-filled cavity called the blastocoel cavity The blastula is a hollow boll consisting of single layer of cells enclosing the blastocoel. This cavity gets completely filled up with cells budded from the wall of the blastula. The embryo is now called stereo gastrula or solid gastrula. The embryo is set free from the egg membrane as a free-swimming larva called the planula the most accurate counts of cells in the blastula and of somites during segmentation. Moreover, prim stages refer to the position of a structure, the primordium of the posterior lateral line, that one must use Nomarski optics to see for the sharpest determination of stages during much of the pharyngula period. The embryo i

Blastula Stage: Definition, Formation & Transitions

Fertilization and Early Embryonic Development Boundless

Lab Practical 1 - Biology 110 with Mary Staton at Wake

Blastocyst Development - Embryolog

Cleavage is the repeated mitotic division of zygote to form a solid ball of cells called morula which later changes into a hollow ball of cells called blastula. Cleavage of human zygote occurs within the fallopian tube. It is holoblastic, i.e., it divides the zygote completely into daughter cells or blastomeres The size and structure of Xenopus laevis (African clawed frogs) embryos have made the species into a model organism for early developmental study. The following is a detailed explanation of gastrulation in Xenopus ; while gastrulation varies across species, studies in Xenopus have shed considerable light on the process in general Describe the molecules that control the cell cycle through positive and negative regulation. The length of the cell cycle is highly variable, even within the cells of a single organism. In humans, the frequency of cell turnover ranges from a few hours in early embryonic development, to an average of two to five days for epithelial cells, and to. Describe 4 similarities between the onion cell root cell and whitefish blastula in mitosis. 1 Educator answer. Science

CELL CYCLE AND MITOSIS Nuclear and Cytoplasmic Division in the Eukarya. Mitosis is the name for the kind of cell division that produces a greater number of cells = cell multiplication; after division, the daughter cells are about half the size of their parent, and they grow before division occurs again.A cell divides into two daughter cells tht are genetically identical to the original cell. In the last chapter, we discussed the specification of early embryonic cells by their acquisition of different cytoplasmic determinants that had been stored in the oocyte. The cell membranes establish the region of cytoplasm incorporated into each new blastomere, and it is thought that the morphogenetic determinants then direct differential gene expression in these blastomeres

blastula, a hollow ball of cells—early, middle, and late stages are determined by cell size, which gets smaller with each round of mitosis; gastrula in which the surface pushes into the interior at a point called the blastopore to form a tube that will become the digestive system. The blastopore is the future anus of the starfish Balbharati solutions for Biology 12th Standard HSC for Maharashtra State Board chapter 2 (Reproduction in Lower and Higher Animals) include all questions with solution and detail explanation. This will clear students doubts about any question and improve application skills while preparing for board exams. The detailed, step-by-step solutions will help you understand the concepts better and. The blastula is usually a spherical layer of cells (the blastoderm) surrounding a fluid-filled or yolk-filled cavity (the blastocoel). Mammals at this stage form a structure called the blastocyst, characterized by an inner cell mass that is distinct from the surrounding blastula. kvargli6h and 42 more users found this answer helpful The blastula is an embryonic structure that is formed from one cell layer. This later forms the three cell layered gastrula. All of the layers of the organism are formed from these three layers

After morula, a 64-celled stage is formed which is called blastula. Blastula contains a fluid filled cavity called blastocoel. This embryo is called blastocyst. So, the correct answer that describes a blastula is ' A hollow ball of cells with a fluid-filled cavity called a blastocoel' called a blastula. This process in shown in the diagram below. Zygote Eight-cell stage Blastula cross section (a) The photograph below shows a cell of a blastula of the whitefish, Coregonus, at one stage of mitosis. Magnification ×1000 Put a cross in the box next to the correct word to complete the following statement

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2 Explain the steps of parturition 3 Explain the

You need to know the process of human development from zygote to birth. For the male reproductive system, you will need to know the seminal vesicle, prostate gland, vas deferens, urethra, epididymis, scrotum, penis, and testes. For the female reproductive system, you will need to know the ovaries, oviduct (fallopian tube), uterus, cervix, and. c. Describe the structure of a human sperm. Answer: a. In testis, the immature male germ cells (spermatogonia) produce sperms by spermatogenesis that begins at puberty. k' At Puberty b. The structure of a sperm is divided into a head, neck, a middle piece and a tail. A plasma membrane envelops the whole body of sperm During the blastula stage, cells no longer cleave synchronously: as development proceeds, divisions of local groups of cells remain synchronous, but these regions gradually decrease in size, and eventually the cell cycle lengthens and becomes largely randomized (Dan . et at., 1980). The early blastula is an epithelial monolayer enclosing In the following slides, we'll explore the basic characteristics shared by all (or at least most) animals, from snails and zebras to mongooses and sea anemones: multicellularity, eukaryotic cell structure, specialized tissues, sexual reproduction, a blastula stage of development, motility, heterotrophy and possession of an advanced nervous system

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The blastocyst differs from the blastula in that it is composed of two already differentiated cell types, the inner cell mass and the enveloping layer, trophoblast. The inner mass of cells are destined to become the embryo proper and an outer rim of cells called the trophoblast Before gastrulation, a unicellular zygote must divide many times to form a ball of cells called a blastula. This process is known as fission and has different patterns in different organisms.The blastula of different organisms can take many different shapes. Some blastulas are a hollow ball of cells, others are a solid ball of cells, while other types retain yolks as an energy source and form. Fig. 1. Characteristics of Xenopus laevis early development. ( A) The different cell cycles and the external appearance of (a) the fertilized egg, and (b) two-cell, (c) mid-blastula and (d) early gastrula stages. Aa and Ab are views from the animal pole, Ac from the side and Ad from the vegetal pole The most obvious difference: a sperm cell is a reproductive cell of males while egg cells are of females. Both egg cells and sperm cells depend on each other for the reproduction of a human life. Both egg cells and sperm cells undergo meiosis. Sperm cells are developed in the epididymis, while egg cells develop in the woman's ovaries Describe the structure and function of the four major groups of organic compounds. blastula, gastrula, germ layer development). List the body systems and the germ layer from which each is derived. Name and describe the functions of and fates of the four fetal membranes

Blastulation - Wikipedi

· Blastula: Blastula is an animal embryo at the early stage of development when it is a hollow ball of cells. Gastrula: Gastrula is an embryo at the stage following the blastula, when it is a hollow cup-shaped structure having three layers of cells. Formation. Blastula: Blastula is formed from the morula in the process called blastulation Both the morula and blastocyst refer to the earliest stages of an embryo. After 3-4 days of the egg being inseminated the embryo cells assume a spherical shape. This transition is known as the morula. After 4-5 days, a cavity forms within the embr.. The Five Kingdoms Of Life. The Amazing Diversity Of Living Systems. Living organisms are subdivided into 5 major kingdoms, including the Monera, the Protista (Protoctista), the Fungi, the Plantae, and the Animalia.Each kingdom is further subdivided into separate phyla or divisions.Generally animals are subdivided into phyla, while plants are subdivided into divisions 2. Describe the changes in uterus at time of implantation. 3. Explain the process of cleavage 4. Explain the formation of morula and blastula 5. Describe the formation of inner and outer cell mass within the blastocyst cavity 6. Appraise abnormal sites for implantation (ectopic pregnancy) and its clinical significance. LGIS MCQs/ SEQs/ SAQs draw the blastula stage of a sea urchin, frog, and bird (label the blastocoel in each) draw a mammalian blastocyst and explain how in differs from the blastula of the above animals (label the inner cell mass and trophoblast) 3. Regarding gastrulation: describe the general process of gastrulation and indicate how it establishes the animal body pla

The placenta is a structure that transfers nutrients to the baby and removes his/her wastes. 3. Embryo Development: As the blastocyst reaches the final steps in the implantation process into the inner lining of the uterus, it evolves into a structure called an embryo. This is the time when internal organs and external structures develop Describe the structure of mammary glands of a human female with labelled diagram. Answer: A mammary gland consists of glandular tissue and variable quantity of fat. The glandular tissue is divided into 15 - 20 mammary lobes and each lobe contains clusters of cells called alveoli, which opens into mammary tubules The structure and function of plants, specifically flowering plants, will be on the exam. Practice labeling the various parts of the plants and recalling their functions. You'll need to remember how plants transport and absorb water, minerals, and food. Describe the life-cycle of plants as well as how they reproduce Proterostomic versus Deuterostomic development. The majority of coelomate invertebrates develop as protostomes (first mouth) in which the oral end of the animal develops from the first developmental opening, the blastopore.In the deuterostomes (second mouth: cf.Deuteronomy, second book of the law), including Echinodermata and the ancestors of the Chordata, the oral end of the animal.

A structure is something of many parts that is put together. A structure can be a skyscraper, an outhouse, your body, or a sentence Ed Reschke/Photolibrary/Getty Images. Before a dividing cell enters mitosis, it undergoes a period of growth called interphase. About 90 percent of a cell's time in the normal cell cycle may be spent in interphase. G1 phase: The period prior to the synthesis of DNA.In this phase, the cell increases in mass in preparation for cell division Mitosis is the mechanism that allows the nuclei of cells to split and provide each daughter cell with a complete set of chromosomes during cellular division. This, coupled with cytokinesis (division of the cytoplasm), occurs in all multicellular plants and animals to permit growth of the organism. In this part of the Photo Gallery, we. The blastula is usually a spherical layer of cells (the blastoderm) surrounding a fluid-filled or yolk-filled cavity (the blastocoel). Mammals at this stage form a structure called the blastocyst, characterized by an inner cell mass that is distinct from the surrounding blastula. The blastocyst must not be confused with the blastula; even. Biology 10 - Reproduction and Development. Reproduction and Development. The reproductive system makes it possible for organisms to pass on their genes to the next generation. There are many different ways to accomplish the task, but ultimately new individuals will develop and enter the world. In this section you will get a brief introduction.

Blastocyst - Wikipedi

What is fate map of Blastula? A fate map is a diagram of an egg or blastula, indicating the fate of each cell or region, at a later stage of development. Fate maps are essential tool in most embryological experiments. They provide researchers with information on which portions of the embryo will normally become which larval or adult structure 4. After the blastula hatches, changes in cells shape and migration begin to occur. Which cells undergo epithelial- mesenchymal transition (EMT)? What are they differentiated into? What structure do they eventually form? Why are these cells the only ones to migrate and not the rest of the blastula cells Desmosomes are anchoring junctions - mechanical couplings scattered like rivets along the sides of adjacent cells to prevent their separation. On the cytoplasmic face of each plasma membrane is a thickening called a plaque. Adjacent cells are held together by thin linker protein filaments that extend from the plaques and fit together like the teeth of a zipper in the intercellular space

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Structure and main features of a spindle apparatus. Image from Purves et al., Life: The Science of Biology, 4th Edition, by Sinauer Associates (www.sinauer.com) and WH Freeman (www.whfreeman.com), used with permission. The phases of mitosis are sometimes difficult to separate. Remember that the process is a dynamic one, not the static process. The animal kingdom includes a great diversity of living species and an even greater diversity of extinct ones; The common ancestor of living animals may have lived between 675 and 800 million years ag Exercise 7a and 7b- DNA Electrophoresis and Structure. 1. Be able to describe a nucleotide, and the structure of DNA. 2. Be able to describe the orientation of the complementary strands of DNA. 3. Be able to describe the type of chemical bonding using to connect the nitrogen bases as well as nucleotides. 4

Implantation - Embryolog

Extraembryonic membranes are membranous structures that appear parallel to the embryo and which play important roles in embryonic development. They form from the embryo but do not become part of the individual organism after its birth The cell goes through 4 steps (prophase, metaphase, anaphase, and telophase.) The cells at the end of the process also have the same amount of chromosomes as the parent cell. At the end, 2 cells are produced. Mitosis is used to make body cells, and occurs in the body

Head and Neck Embryology and Infant Skull DevelopmentLecture - Week 1 and 2 Development - Embryology