1. The document discusses cell division and the process of mitosis and meiosis. It provides details on the stages of each type of cell division, including interphase, prophase, metaphase, anaphase, and telophase.
2. Meiosis produces gametes through two divisions and results in four haploid cells, while mitosis results in two identical diploid daughter cells. The main differences between mitosis and meiosis are also summarized.
3. Cell division through mitosis and meiosis is important for various biological functions like growth of multicellular organisms, asexual reproduction, wound healing, and regeneration. Meiosis and sexual reproduction also help in genetic variation and evolution of species.
Continuation of the cell structure and function. This presentation highlights the cell cycle and concentrate on how cell division occur and the steps involved in cell dividing.
2018/2019
Continuation of the cell structure and function. This presentation highlights the cell cycle and concentrate on how cell division occur and the steps involved in cell dividing.
2018/2019
Cell cycle & Mitosis presentation to help understand the basic concepts related to the topic. This topic is included in the Maharashtra Board curriculum for XIth Std Biology paper. All videos inserted in this powerpoint have their respective copyrights. Unauthorized distribution and copying of the same is prohibited
It is the presentation on the MEIOSIS phase of the Cell division.
It includes all the details and definitions that are related to the topic of meiosis with the labelled diagrams.
If you have any query or a question, you may ask in the comment box.
thanks.
A detailed presentation for the digestive system to be thought on grade 8 level (Department of Education Philippines Standards) including parts, functions, nutrients and diseases.
This presentation explains the topic of CELL CYCLE and CELL DIVISION.
It includes cell mitosis of both Plant cell and Animal cell with labelled diagrams.
Cell cycle & Mitosis presentation to help understand the basic concepts related to the topic. This topic is included in the Maharashtra Board curriculum for XIth Std Biology paper. All videos inserted in this powerpoint have their respective copyrights. Unauthorized distribution and copying of the same is prohibited
It is the presentation on the MEIOSIS phase of the Cell division.
It includes all the details and definitions that are related to the topic of meiosis with the labelled diagrams.
If you have any query or a question, you may ask in the comment box.
thanks.
A detailed presentation for the digestive system to be thought on grade 8 level (Department of Education Philippines Standards) including parts, functions, nutrients and diseases.
This presentation explains the topic of CELL CYCLE and CELL DIVISION.
It includes cell mitosis of both Plant cell and Animal cell with labelled diagrams.
This mitosis Power point will enhance all individuals who were unsure about some of the things in mitosis as they explain the mitosis process very precise.
CELL DIVISION- Decoding Cell Division: The Dance of Life's ContinuityNursing Mastery
Decoding Cell Division: The Dance of Life's Continuity
Step into the mesmerizing world of cell division with our illuminating SlideShare presentation. From the elegant choreography of mitosis to the intricacies of meiosis, witness the remarkable processes that underpin life's continuity and diversity.
In this captivating presentation, we delve deep into the mechanisms of cell division, unraveling the stages and significance of mitosis and meiosis. Explore how cells meticulously replicate their DNA, segregate their chromosomes, and orchestrate their division to ensure the transmission of genetic information with precision and fidelity.
Through vivid illustrations, clear explanations, and real-world examples, we illuminate the significance of cell division in growth, development, and reproduction. Gain a newfound understanding of how errors in cell division can lead to diseases like cancer and genetic disorders, and learn about the cutting-edge research driving advancements in this field.
Whether you're a student, educator, or enthusiast of life sciences, our presentation offers valuable insights into one of the most fundamental processes of life. Join us as we unravel the mysteries of cell division and marvel at the beauty and complexity of nature's continuity.
Don't miss this opportunity to deepen your knowledge and appreciation of cell biology. Embark on a journey into the heart of cell division and discover the dance of life's continuity unfolding before your eyes.
CRISPR-Cas9, a revolutionary gene-editing tool, holds immense potential to reshape medicine, agriculture, and our understanding of life. But like any powerful tool, it comes with ethical considerations.
Unveiling CRISPR: This naturally occurring bacterial defense system (crRNA & Cas9 protein) fights viruses. Scientists repurposed it for precise gene editing (correction, deletion, insertion) by targeting specific DNA sequences.
The Promise: CRISPR offers exciting possibilities:
Gene Therapy: Correcting genetic diseases like cystic fibrosis.
Agriculture: Engineering crops resistant to pests and harsh environments.
Research: Studying gene function to unlock new knowledge.
The Peril: Ethical concerns demand attention:
Off-target Effects: Unintended DNA edits can have unforeseen consequences.
Eugenics: Misusing CRISPR for designer babies raises social and ethical questions.
Equity: High costs could limit access to this potentially life-saving technology.
The Path Forward: Responsible development is crucial:
International Collaboration: Clear guidelines are needed for research and human trials.
Public Education: Open discussions ensure informed decisions about CRISPR.
Prioritize Safety and Ethics: Safety and ethical principles must be paramount.
CRISPR offers a powerful tool for a better future, but responsible development and addressing ethical concerns are essential. By prioritizing safety, fostering open dialogue, and ensuring equitable access, we can harness CRISPR's power for the benefit of all. (2998 characters)
CHAPTER 1 SEMESTER V - ROLE OF PEADIATRIC NURSE.pdfSachin Sharma
Pediatric nurses play a vital role in the health and well-being of children. Their responsibilities are wide-ranging, and their objectives can be categorized into several key areas:
1. Direct Patient Care:
Objective: Provide comprehensive and compassionate care to infants, children, and adolescents in various healthcare settings (hospitals, clinics, etc.).
This includes tasks like:
Monitoring vital signs and physical condition.
Administering medications and treatments.
Performing procedures as directed by doctors.
Assisting with daily living activities (bathing, feeding).
Providing emotional support and pain management.
2. Health Promotion and Education:
Objective: Promote healthy behaviors and educate children, families, and communities about preventive healthcare.
This includes tasks like:
Administering vaccinations.
Providing education on nutrition, hygiene, and development.
Offering breastfeeding and childbirth support.
Counseling families on safety and injury prevention.
3. Collaboration and Advocacy:
Objective: Collaborate effectively with doctors, social workers, therapists, and other healthcare professionals to ensure coordinated care for children.
Objective: Advocate for the rights and best interests of their patients, especially when children cannot speak for themselves.
This includes tasks like:
Communicating effectively with healthcare teams.
Identifying and addressing potential risks to child welfare.
Educating families about their child's condition and treatment options.
4. Professional Development and Research:
Objective: Stay up-to-date on the latest advancements in pediatric healthcare through continuing education and research.
Objective: Contribute to improving the quality of care for children by participating in research initiatives.
This includes tasks like:
Attending workshops and conferences on pediatric nursing.
Participating in clinical trials related to child health.
Implementing evidence-based practices into their daily routines.
By fulfilling these objectives, pediatric nurses play a crucial role in ensuring the optimal health and well-being of children throughout all stages of their development.
The dimensions of healthcare quality refer to various attributes or aspects that define the standard of healthcare services. These dimensions are used to evaluate, measure, and improve the quality of care provided to patients. A comprehensive understanding of these dimensions ensures that healthcare systems can address various aspects of patient care effectively and holistically. Dimensions of Healthcare Quality and Performance of care include the following; Appropriateness, Availability, Competence, Continuity, Effectiveness, Efficiency, Efficacy, Prevention, Respect and Care, Safety as well as Timeliness.
Leading the Way in Nephrology: Dr. David Greene's Work with Stem Cells for Ki...Dr. David Greene Arizona
As we watch Dr. Greene's continued efforts and research in Arizona, it's clear that stem cell therapy holds a promising key to unlocking new doors in the treatment of kidney disease. With each study and trial, we step closer to a world where kidney disease is no longer a life sentence but a treatable condition, thanks to pioneers like Dr. David Greene.
Struggling with intense fears that disrupt your life? At Renew Life Hypnosis, we offer specialized hypnosis to overcome fear. Phobias are exaggerated fears, often stemming from past traumas or learned behaviors. Hypnotherapy addresses these deep-seated fears by accessing the subconscious mind, helping you change your reactions to phobic triggers. Our expert therapists guide you into a state of deep relaxation, allowing you to transform your responses and reduce anxiety. Experience increased confidence and freedom from phobias with our personalized approach. Ready to live a fear-free life? Visit us at Renew Life Hypnosis..
How many patients does case series should have In comparison to case reports.pdfpubrica101
Pubrica’s team of researchers and writers create scientific and medical research articles, which may be important resources for authors and practitioners. Pubrica medical writers assist you in creating and revising the introduction by alerting the reader to gaps in the chosen study subject. Our professionals understand the order in which the hypothesis topic is followed by the broad subject, the issue, and the backdrop.
https://pubrica.com/academy/case-study-or-series/how-many-patients-does-case-series-should-have-in-comparison-to-case-reports/
Welcome to Secret Tantric, London’s finest VIP Massage agency. Since we first opened our doors, we have provided the ultimate erotic massage experience to innumerable clients, each one searching for the very best sensual massage in London. We come by this reputation honestly with a dynamic team of the city’s most beautiful masseuses.
Defecation
Normal defecation begins with movement in the left colon, moving stool toward the anus. When stool reaches the rectum, the distention causes relaxation of the internal sphincter and an awareness of the need to defecate. At the time of defecation, the external sphincter relaxes, and abdominal muscles contract, increasing intrarectal pressure and forcing the stool out
The Valsalva maneuver exerts pressure to expel faeces through a voluntary contraction of the abdominal muscles while maintaining forced expiration against a closed airway. Patients with cardiovascular disease, glaucoma, increased intracranial pressure, or a new surgical wound are at greater risk for cardiac dysrhythmias and elevated blood pressure with the Valsalva maneuver and need to avoid straining to pass the stool.
Normal defecation is painless, resulting in passage of soft, formed stool
CONSTIPATION
Constipation is a symptom, not a disease. Improper diet, reduced fluid intake, lack of exercise, and certain medications can cause constipation. For example, patients receiving opiates for pain after surgery often require a stool softener or laxative to prevent constipation. The signs of constipation include infrequent bowel movements (less than every 3 days), difficulty passing stools, excessive straining, inability to defecate at will, and hard feaces
IMPACTION
Fecal impaction results from unrelieved constipation. It is a collection of hardened feces wedged in the rectum that a person cannot expel. In cases of severe impaction the mass extends up into the sigmoid colon.
DIARRHEA
Diarrhea is an increase in the number of stools and the passage of liquid, unformed feces. It is associated with disorders affecting digestion, absorption, and secretion in the GI tract. Intestinal contents pass through the small and large intestine too quickly to allow for the usual absorption of fluid and nutrients. Irritation within the colon results in increased mucus secretion. As a result, feces become watery, and the patient is unable to control the urge to defecate. Normally an anal bag is safe and effective in long-term treatment of patients with fecal incontinence at home, in hospice, or in the hospital. Fecal incontinence is expensive and a potentially dangerous condition in terms of contamination and risk of skin ulceration
HEMORRHOIDS
Hemorrhoids are dilated, engorged veins in the lining of the rectum. They are either external or internal.
FLATULENCE
As gas accumulates in the lumen of the intestines, the bowel wall stretches and distends (flatulence). It is a common cause of abdominal fullness, pain, and cramping. Normally intestinal gas escapes through the mouth (belching) or the anus (passing of flatus)
FECAL INCONTINENCE
Fecal incontinence is the inability to control passage of feces and gas from the anus. Incontinence harms a patient’s body image
PREPARATION AND GIVING OF LAXATIVESACCORDING TO POTTER AND PERRY,
An enema is the instillation of a solution into the rectum and sig
Antibiotic Stewardship by Anushri Srivastava.pptxAnushriSrivastav
Stewardship is the act of taking good care of something.
Antimicrobial stewardship is a coordinated program that promotes the appropriate use of antimicrobials (including antibiotics), improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms.
WHO launched the Global Antimicrobial Resistance and Use Surveillance System (GLASS) in 2015 to fill knowledge gaps and inform strategies at all levels.
ACCORDING TO apic.org,
Antimicrobial stewardship is a coordinated program that promotes the appropriate use of antimicrobials (including antibiotics), improves patient outcomes, reduces microbial resistance, and decreases the spread of infections caused by multidrug-resistant organisms.
ACCORDING TO pewtrusts.org,
Antibiotic stewardship refers to efforts in doctors’ offices, hospitals, long term care facilities, and other health care settings to ensure that antibiotics are used only when necessary and appropriate
According to WHO,
Antimicrobial stewardship is a systematic approach to educate and support health care professionals to follow evidence-based guidelines for prescribing and administering antimicrobials
In 1996, John McGowan and Dale Gerding first applied the term antimicrobial stewardship, where they suggested a causal association between antimicrobial agent use and resistance. They also focused on the urgency of large-scale controlled trials of antimicrobial-use regulation employing sophisticated epidemiologic methods, molecular typing, and precise resistance mechanism analysis.
Antimicrobial Stewardship(AMS) refers to the optimal selection, dosing, and duration of antimicrobial treatment resulting in the best clinical outcome with minimal side effects to the patients and minimal impact on subsequent resistance.
According to the 2019 report, in the US, more than 2.8 million antibiotic-resistant infections occur each year, and more than 35000 people die. In addition to this, it also mentioned that 223,900 cases of Clostridoides difficile occurred in 2017, of which 12800 people died. The report did not include viruses or parasites
VISION
Being proactive
Supporting optimal animal and human health
Exploring ways to reduce overall use of antimicrobials
Using the drugs that prevent and treat disease by killing microscopic organisms in a responsible way
GOAL
to prevent the generation and spread of antimicrobial resistance (AMR). Doing so will preserve the effectiveness of these drugs in animals and humans for years to come.
being to preserve human and animal health and the effectiveness of antimicrobial medications.
to implement a multidisciplinary approach in assembling a stewardship team to include an infectious disease physician, a clinical pharmacist with infectious diseases training, infection preventionist, and a close collaboration with the staff in the clinical microbiology laboratory
to prevent antimicrobial overuse, misuse and abuse.
to minimize the developme
Global launch of the Healthy Ageing and Prevention Index 2nd wave – alongside...ILC- UK
The Healthy Ageing and Prevention Index is an online tool created by ILC that ranks countries on six metrics including, life span, health span, work span, income, environmental performance, and happiness. The Index helps us understand how well countries have adapted to longevity and inform decision makers on what must be done to maximise the economic benefits that comes with living well for longer.
Alongside the 77th World Health Assembly in Geneva on 28 May 2024, we launched the second version of our Index, allowing us to track progress and give new insights into what needs to be done to keep populations healthier for longer.
The speakers included:
Professor Orazio Schillaci, Minister of Health, Italy
Dr Hans Groth, Chairman of the Board, World Demographic & Ageing Forum
Professor Ilona Kickbusch, Founder and Chair, Global Health Centre, Geneva Graduate Institute and co-chair, World Health Summit Council
Dr Natasha Azzopardi Muscat, Director, Country Health Policies and Systems Division, World Health Organisation EURO
Dr Marta Lomazzi, Executive Manager, World Federation of Public Health Associations
Dr Shyam Bishen, Head, Centre for Health and Healthcare and Member of the Executive Committee, World Economic Forum
Dr Karin Tegmark Wisell, Director General, Public Health Agency of Sweden
2. Cells reproduce by dividing into two in the process called
cell division
Each dividing cell is called mother cell or parent cell,
and its descendants are called daughter cells
The parent cell transmits copies of its hereditary
information (DNA) to its daughter cells which in turn,
pass it to their own daughter cells, becoming yet another
parent cell, and so on and so forth
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3. As a cell prepares to divide, the DNA inside
the nucleus becomes organized into
chromosomes
This is to ensure that both of the new cells
get all of the genetic information from the
original cell
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4. Chromosomes are rod shaped structures
made of DNA and proteins found in the nucleus of
cells
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5. Chromosomes consist of 2 identical
halves called chromatids
– When a cell divides, each of the two
new cells will receive one chromatid
• Two chromatids are attached at the
centromere
Between cell divisions, DNA is not so
tightly
coiled
• This form is called chromatin
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6. Animal chromosomes are categorized as either sex
chromosomes or autosomes
– Sex chromosomes determine the sex of an
organism
• In humans, sex chromosomes are X or Y
(females = XX, males = XY)
– All of the other chromosomes are autosomes
Every cell of an organism produced by sexual reproduction
has two copies of each autosome (one from each parent)
• The two copies are called homologous chromosomes
– Same size and shape and carry genes for the same traits
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7. Diploid – cells that have
2 sets of chromosomes (46 total in humans)
Haploid – cells that only
have 1 set of chromosomes (23 total in humans)
• Only sperm and egg cells are haploid
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8. Cell division is often referred to as cellular reproduction
Most prokaryotic cells, by simply separating the contents
of the cell into two parts
Eukaryotic cells can divide either through a process
called mitosis or meiosis.
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9. Binary fission is the division of a prokaryotic
cell into two offspring cells
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10. Two types of cell division
– Mitosis results in new cells that are
identical to the original cell
– Meiosis occurs during the formation of
gametes (haploid reproductive cells)
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11. A repeating set of
events in the life of a
cell
• Division is one phase of
the cycle
• Time between cell
divisions is called
interphase
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12. 1. G1 phase – offspring cells grow to mature
size
2. S phase – the cell’s DNA is copied
3. G2 phase – cell prepares for cell division
• Cells can exit the cycle and enter into the G0
phase to stop dividing (ex: fully developed brain
cells)
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Prophase (Gk. Pro – before or first,
phasis – appearance or stage
DNA condenses into chromosomes
• Nuclear membrane breaks down
• Centrosomes form and
microtubules grow from them (called
the mitotic spindle)
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Metaphase (Gk. Meta – after or
second, phasis – stage)
Chromosomes line up in
the middle of the cell
• Spindle fibers attach to
the centromere of each
chromosome
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Anaphase: (Gk. Ana – up,
phasis – appearance or stage)
Chromatids are pulled
apart and move to opposite
ends of the cell.
It lasts only for few minutes
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Surface to Volume Ratio: Increase in cell size reduces surface area
to volume ratio and decreases efficiency in exchange of materials.
Nucleo-cytoplasmic Ratio: Nucleus controls all metabolic activities
occuring in the cytoplasm. Increased volume of cytoplasm due to
cell growth reduces the nucleo-cytoplasmic ratio.
Equitable distribution of genetic material: Qualitative and
quantitative equitable distribution of chromosomes in all the body
cells of an organism by mitotic divisions maintains similar genetic
constitution in them.
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Growth of Multicellular Organisms: It occurs due to increase in
number of cells rather than increase in cell size because smaller
cells are more efficient.
Asexual Reproduction: It helps in vegetative propagation of
plants and asexual reproduction in lower organisms. Unicellular
organisms multiply by this method.
Healing of wounds: Mitotic divisions in healthy cells surrounding
the area of injury help in healing the wounds.
Regeneration: The lost organs in plants and animals like
earthworm, tail of lizard can be regenerated by mitosis.
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A cell spends most of its time in interphase
• What tells the cells to exit interphase and
begin dividing?
• There are three main checkpoints that act as
“traffic signals” for the cell to divide or not to
divide
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1. Cell growth (G1)
checkpoint – controls whether
the cell will divide
2. DNA synthesis (G2)
checkpoint – make sure DNA
was copied properly
3. Mitosis checkpoint –
signals tell the cell to exit mitosis
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• If a mutation occurs in one of the genes that
regulates the cell cycle, cell growth and
division could be disrupted
• This disruption could lead to cancer – the
uncontrolled growth of cells
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• A process of nuclear division that reduces the
number of chromosomes in new cells to half
the number in the original cell
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• Meiosis produces gametes, which are haploid
reproductive cells
• Cells preparing to divide by meiosis undergo the
G1, S, and G2 phases of interphase
– Cells begin meiosis with a duplicate set of
chromosomes, just like mitosis
• Cells undergoing meiosis divide twice, resulting
in 4 haploid (1n) cells
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• First cell division = Meiosis I
– Prophase I, Metaphase I, Anaphase I, Telophase I
and Cytokinesis I
• Second cell division = Meiosis II
– Prophase II, Metaphase II, Anaphase II,
Telophase II and Cytokinesis II
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• DNA coils tightly into chromosomes
• Spindle fibers appear
• Nuclear membrane is assembles
• Synapsis occurs - homologous chromosomes
line up next to each other
– Each pair is called a tetrad
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• Crossing-over occurs – portions of
chromatids may break off and attach to
adjacent
chromatids
• Genetic recombination results –
genetic material between maternal and
paternal chromosomes is exchanged
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• Tetrads line up along
the middle of the cell
• Spindle fibers attach to
the centromere of each
homologous
chromosome
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• Each homologous chromosome
moves to an opposite end of the
cell
• Random separation of homologous
chromosomes is called independent
assortment and results in genetic
variation
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• Chromosomes reachopposite
ends of thecell and cytokinesis
begins
• Two new cells areproduced, each
containing onechromosome from
each homologous pair (haploid –
1n)
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• Spindle fibers form and
begin to move the
chromosomes toward
the midline of the
dividing cell
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• Chromatids separate
and move toward
opposite ends of the
cell
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• Telophase II – nuclear
membrane forms around the
chromosomes in each of the
four new cells
• Cytokinesis II – 4 new cells
are formed, each with half of
the original cell’s number of
chromosomes
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• Telophase II – nuclear
membrane forms around the
chromosomes in each of the
four new cells
• Cytokinesis II – 4 new cells
are formed, each with half of
the original cell’s number of
chromosomes
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MITOSIS
Occurs in somatic or body
cells
Direct cellular division
Produce two diploid
daughter cells
The daughter cells are
exactly alike
MEIOSIS
Occurs in reproductive
cells or gametes
Has two successive division
(meiosis I and meiosis II)
Produce four haploid
daughter cells
The daughter cells are not
all alike
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Gametes (egg & sperm)
form
Four haploid cells with one
copy of each chromosome
One allele of each gene
Different combinations of
alleles for different genes
along the chromosome
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• In animals, the only cells that
divide by meiosis are those
that produce gametes within
the reproductive organs
– In humans – testes
(males) and ovaries (females)
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SPERMATOGENESIS
• In the testes – male gametes
known as sperm cells or
spermatozoa are produced
• One diploid cell divides
meiotically to form four haploid
cells called spermatids – each
develops into a mature sperm cells
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OOGENESIS
• Production of mature egg cells, or
ova
• A diploid reproductive cell
divides meiotically to produce one
mature egg cell (ovum) and three
polar bodies which will degenerate
– cytoplasm is not evenly
distributed in cytokinesis
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• Production of offspring through meiosis and
the union of a sperm and an egg
• Offspring are genetically different because genes
are combined in new ways
• Advantage: enables species to adapt rapidly to
new conditions
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Sexual Reproduction: Meiosis and fertilization are essential
in the life cycle of sexually reproducing organisms.
Maintenance of Chromosome Number: Fertilization of
haploid gametes doubles the chromosome number in the
zygote. Meiosis halves the chromosome number during
different stages of life cycle. Thus, it helps in maintaining the
same chromosome number in a species.
Segregation of Alleles: Meiosis helps in segregation of
alleles of different characters due to disjunction of
homologous chromosomes of each bivalent in meiosis-I.
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Crossing over: Crossing over between non-sister chromatids
of paternal and maternal homologous chromosomes of each
bivalent during prophase-I of meiosis helps in recombination
of linked genes.
Gene Mutations: The chances of gene mutations increase
during meiosis due to breakage and reunion of DNA
molecules during crossing over. Mutations are fountain head
of all variations.
Evolution: Variations produced during meiosis from the basis
of evolution due to natural selection of better recombinants.
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The cell cycle is regulated to fit the needs of the organism.
Important discoveries in the last decade helped to understand
the regulation of cell cycle and how abnormalities in cell cycle
regulation contribute to the development of cancer.
Gene therapy technique to repair the genetic defects that cause
cancer.