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Wordwall - Create better lessons quicker

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Labelled diagram - Drag and drop the pins to their correct place on the image.

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Use this interactive to label some parts of the human digestive system. Drag and drop the text labels onto the boxes next to the diagram. Selecting or hovering over a box will highlight each area in the diagram.

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Worksheets and lesson ideas to challenge students aged 11 to 16 to think hard about mitosis and meiosis (GCSE and Key Stage 3)

Mitosis and meiosis teacher brief

Overview: it's strange to think that once upon a time we were all just one cell. Cell division enables organisms to grow, replace damaged tissue and reproduce. Mitosis is the cell division associated with growth and asexual reproduction. One parent cell splits into two daughter cells following the replication (duplication) of the genetic material inside the nucleus. The daughter cells produced by mitosis are identical to the parent except for any mutations that may have taken place. Meiosis in contrast is the cell division associated with sexual reproduction. Here, one parent cell forms four haploid gametes, each containing half the amount of genetic information as their parent. Importantly, meiosis produces daughter cells that are different from each other and the parent cell - it introduces variation. Cancer is a disease caused by uncontrolled cell division - it's when mitosis goes wrong. Many drugs that target cancer cells also target cells that divide - that's one of the reasons for hair dropping out during chemotherapy.

Key concept: cell division allows organisms to grow, replace damaged tissue and reproduce. When cell division is uncontrolled we get important human diseases such as cancer.

From big idea: organisms are organised on a cellular basis and have a finite life span

Prior knowledge: ell structure, chromosomes and genetic organisation inside the nucleus

Misconception [scientific idea]: growth is a result of cells getting bigger [growth is mainly a result of cell division]; organelles disappear during cell division [organelles remain present during cell division]; the cell cycle is mitosis [the cell cycle comprises DNA replication, mitosis and cytokinesis]

Teaching resources

Where to start?

Ask students to watch this excellent video showing a fertilised human egg undergoing its first few mitotic divisions. Then show a human karyotype and ask why chromosomes are arranged in pairs.

Mitosis and general cell division

Key Stage 3 worksheet to identify when cell division occurs. Students are given a series of pictures. They identify whether cell division has taken place. This is a great starting point to introduce mitosis.

Mitosis and the cell cycle

GCSE worksheet on mitosis and the cell cycle. Use this simple activity looking at mosquito chromosomes after you have given students the chance to learn the ideas behind mitosis. Students could work in pairs or individually for this task. ( PDF)

Comparing and contrasting meiosis with mitosis

GCSE worksheet to compare and contrast meiosis with mitosis. This activity asks students to compare and contrast mitosis with meiosis by identifying similarities and differences. It could serve as a good way to recap mitosis once you have introduced meiosis. This activity was based on an idea from The Big Ideas of Physics and How to Teach Them by Ben Rogers. ( PDF)

Meiosis

A Level activity on the stages of meiosis. This resource can be used to help students recognise the different meiotic stages. Students are shown pictures of cells undergoing meiosis. They must identify each meiotic stage and put the images in the correct order. ( PDF)

Videos of cell division

A fantastic collection of videos and images of cells provided by The Cell. These videos are freely available and can be used to show students the dynamic nature of cell division.

Thinking deeper

Suggest why chemotherapy may cause hair to fall out.

Why do people age?

A cancerous cell divides uncontrollably once every hour. How many cancerous cells will be present after 24 hours?

↵ Back to Biology teaching resources

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Cell division teaching resources | the science teacher

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Worksheets and lesson ideas to challenge students aged 11 to 16 to think hard about mitosis and meiosis (GCSE and Key Stage 3) Teaching resources Where to start? Ask students to watch this excellent video showing a fertilised human egg ... Cell division teaching resources Read More "

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Grommet insertion for glue ear in right ear endoscopic

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Can You Hack Your Eyes To See Upside Down?

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Transcript

The embryo is an early developmental stage of animals. In humans the embryo begins to develop about four days after an egg is fertilized. Appearing initially as a tiny mass of cells, it eventually gives rise to the fetus, an obvious human form.

In the first days of the embryo's existence, it journeys along the fallopian tube. About one week after conception, it reaches the uterus, which is prepared to receive it with a network of blood vessels and glands.

By this time, the embryo has become a fluid-filled sphere of nearly 100 cells. Some of the cells become fingerlike projections that anchor the embryo to the uterus to draw nourishment and oxygen and to rid the embryo of wastes. The anchoring cells secrete a hormone that will prevent the disintegration of the lining; there will be no menstrual period.

Three weeks after fertilization, though still smaller than a grain of rice, the embryo has a primitive heart. Through the following weeks its tissues and organs will develop. In four weeks it looks like this...

five weeks, about the size of a pea...

six weeks...

seven weeks.

At two months it is called a fetus.

When the embryo attaches to the uterus, a complex structure of vessels and cells forms, which is called the placenta. A network of the embryo's blood vessels closely intermingles next to the mother's blood supply.

While the blood of the embryo and that of the mother don't actually mix, materials such as oxygen, nutrients, and waste products can pass between mother and embryo. If their blood were to mix, the embryo would be rejected by the mother's immune system. This happens because the embryo essentially is a foreign organism -it shares only half of its genetic constitution with the mother.

From the placenta emerges the umbilical cord, which leads to the abdomen of the fetus. When the cord is removed at birth, the belly button is created. During pregnancy the placenta and umbilical cord serve as pathways for everything the fetus needs to grow.

By the third month all the organs of the fetus are essentially in place, and the fetus enters a period of intense growth. During the fourth month, the fetus doubles in size. Its muscles twitch.

By the fifth month, it is about 8 inches, nearly 21 centimeters long. It kicks occasionally. Its heart rate averages about 140 beats per minute, twice the speed of an adult's. After nine months, it is fully developed and birth occurs.

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Human embryonic and fetal development illustrated

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Learn about human embryonic and fetal development from fertilization to birth.

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The Theory of Evolution (by Natural Selection) | Cornerstones Education

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- [Instructor] Many of you all are probably familiar with the term evolution, and some of you all, I'm guessing, are also familiar with the term natural selection, although it isn't used quite as much as evolution. And what we're going to do in this video is see how these are connected, but we're also going to address some potential misconceptions that folks have about evolution. So when a lot of people think of evolution, they think of a diagram or an image that looks something like this. They can see what they would consider to be a more primitive ancestor evolving into a more sophisticated, a more modern type of organism. And this is going from some type of primitive ape, all the way to human beings. Now there's some aspects of this diagram that give the right idea, that evolution is the phenomenon that organisms over time can evolve, can change in their traits, that can actually become different species. Now the one thing about this diagram that might be misleading is calling this character primitive and somehow imagining that this one in the front is better or more advanced. Evolution doesn't necessarily go from good to bad or primitive to advanced. It's really just continual change based on what is most suitable for the environment in which the organisms are in. And this can take millions of years. For example, the common ancestor of human beings and other apes like chimpanzees or gorillas can be five, 10 million-plus years in the past, but it can also happen right before our eyes. For example, every year we have a new flu virus because the flu virus is constantly evolving through mutation. We have the Coronavirus and we're having new variants of that, it seems like, almost every few months. That is evolution happening right before our eyes. But the key question is, how does this actually happen? Does the DNA know to change into something else? Well, clearly not. The DNA is not sentient. It is not somehow constructing itself. And that's where natural selection comes into the picture. So let's imagine a population, and I'm gonna think about a very abstract population of these little circle-shaped things. And an important characteristic for evolution to happen is that you need variation in the population. And we talk about variation, we're talking about different expressed traits, and you might ask, "Where does that variation actually come from?" Well, it's going to come from mutation. I talked about variation when we think about viruses, the flu virus or the Coronavirus, and it can also come from sexual reproduction, and we go into a lot of detail in other videos how sexual reproduction mixes and matches all of the potential alleles that are in a population so that different members of the population are getting different combinations of those alleles, and so that contributes to variation. And that variation by itself does not lead to evolution. You need variation and selection pressure. And this is really where the term "natural selection" is coming from. What do I mean by selection pressure? Well, in this little example here, if these circles and triangle-looking things could just keep reproducing, they could find as many resources as they need, there's no shortage of food, there's no shortage of environments in which they can live and reproduce, they had no predators, well, you're not gonna have selection pressure. And so all of these variations might have an equal chance of living their life and then reproducing. But now let's introduce some selection pressure and imagine what might happen. Let's say we introduce the selection pressure of a predator that has a much easier time seeing white. Well, then what's going to happen? Well over time, generation to generation, the white circles and triangles here are going to be much more likely to be eaten by that predator before they can reproduce and pass on the allele or the alleles that might result in this white trait, and so next generations or future generations are going to have fewer and fewer of these white shapes, so the next generation might look a lot like this. A lot more of the purple we're seeing and a lot more of the blue. Now on the other hand, you could have a scenario where instead of a predator that sees white and can't see the other colors showing up, where there's a shortage of food. So that's another form of selection pressure. Let's say a more triangular shape is useful for finding food. for food. Well, then what's going to happen? Well, generation by generation, these shapes that are more triangular are going to have a better chance of surviving and reproducing. And so maybe in the first generation you have maybe something like that does reasonably well, something like that could do very well. Something like that would do well. Something like this could do well, but we're gonna see, we might see a few of the circles still. We might see a few of these characters, but we'll see fewer have them. And we're gonna see more of these characters right over here. And now you can imagine if this environmental pressure continues, then over generation and generation, you keep selecting for more triangular, if you could go forward many hundreds or thousands or hundreds of thousands or millions of years, you might see some subset of this population that lives in this environment. They might have a very triangular shape. They might not even look anything like their ancestors. Now, does this mean that this shape right over here is somehow more advanced or better than what their ancestors saw, or maybe there's a cousin species that was where the predators see white and the triangular shape really doesn't help you, and so they have a cousin species that looks like this. There's no way of saying that this species is more advanced or better than this species, but what we can say is, it is more fit for its environment. And this species is more fit in its environment. So I will leave you there, and it's important to realize this isn't some magical process. It's all due to variation caused by mutation and sexual reproduction, selection pressure, and then that change happens over time. And this isn't just something that happens over millions or tens of millions of years. It happens before our eyes every day. When we talk about the different flu strain or a different coronavirus strain or drug-resistant bacteria, it's very relevant to our day-to-day lives.

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Natural selection and evolution (video) | Khan Academy

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Virus structure and classification (video) | Khan Academy

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Learn for free about math, art, computer programming, economics, physics, chemistry, biology, medicine, finance, history, and more. Khan Academy is a nonprofit with the mission of providing a free, world-class education for anyone, anywhere.

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What are viruses? And how do they spread?

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Concerns are growing that the recently-detected coronavirus may spread around the world.

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Viruses are tiny infectious agents that dominate much of the microscopic world.

They're incredibly abundant. There are more viruses in a single drop of seawater than there are people living in New York City. And there are more viruses on Earth than there are stars in the universe.

They've had a lot of time to become so plentiful. Viruses were here long before we were. Some scientists believe they're older than any life on Earth.

They are also incredibly diverse. Viruses can invade all types of life, from animals to plants, bacteria to fungi.

But what are they, exactly?

Viruses aren't technically alive--though that's still a matter of scientific debate; they're merely packets of genetic information. Some carry that code in single strands of RNA, others in double strands or in DNA. But they all use those instructions as a blueprint for invading healthy cells, or "hosts."

They enter and take over a cell to replicate: either destroying the host cell's genetic code or splicing themselves onto it.

After replicating, viruses escape to hijack other cells, often destroying their host cells in a process called "lysis."

This isn't always a bad thing. By breaking and restructuring other cells- like ones inside phytoplankton in the ocean-viruses play an important role of increasing the efficiency of the Ocean's "biological pump": the process of sequestering carbon dioxide from the atmosphere to the ocean floor.

An ancient virus also gave rise to the human placenta, which is why our babies aren't born from eggs.

But those were happy side effects. Viruses only care about one thing: making more viruses. And that often causes big problems.

Starting in the late 1800s, scientists discovered many diseases spread by unknown, unseen pathogens.These mysterious infections were destroying tobacco plants and infecting livestock across Europe and the United States.

In 1902, American physician Walter Reed discovered that a similar agent had been the cause of the Yellow Fever epidemic.

Researchers began calling these pathogens "viruses," Latin for poison.

At the time, Reed and his peers could isolate viruses with cutting-edge filters because they happened to be much smaller than bacteria. But they couldn't actually see them with a regular microscope. The tobacco mosaic virus would be the first to come into actual view with the invention of the electron microscope in the 1930s.

Once we could see viruses, we started to realize that they were everywhere, including inside our own bodies.

Viruses have replicated inside humans throughout our evolution. That's why about eight percent of the human genome is derived from viruses-remnants of infections in our ancient ancestors.

These viruses are generally inactive, or "latent," though some can be reactivated by autoimmune diseases, neurodegenerative conditions, chronic inflammation, and cancer.

In addition to going latent, sometimes for decades, viruses can also mutate. This can happen as a result of physical damage, chemical changes within the virus's genetic material, or errors during the replication process.

Mutation is the reason that the novel coronavirus, SARS-CoV-2, was able to jump from infecting bats to infecting humans-something known as "host-switching."

Coronaviruses in particular have a unique way of mutating: they readily swap bits of RNA with other coronaviruses in a process called " recombination." That makes it easy for the virus to adapt to new species.

The coronavirus pandemic has brought the adaptability of viruses into full view. What remains somewhat hidden is how many more deadly viruses like it might be waiting to jump from animals into humans.

Some estimates give reason for concern. A 2018 study found that of 111 viral families identified worldwide, there are some 631,000 to 827,000 yet-unknown viruses that "likely have the capacity to infect people."

It's unclear how many of them could one day pose a threat to humans. But what is clear is that we still have so much to learn about the multitudes of viruses that share the world with us.

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Michael Tabb, Andrea Gawrylewski, Jeffery DelViscio

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Viruses are tiny infectious agents that dominate much of the microscopic world. They're incredibly abundant. There are more viruses in a single drop of seawater than there are people living in New York City. And there are more viruses on Earth than there are stars in the universe.

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What are viruses | Cells | Biology | FuseSchool

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THE HUMAN BONES SONG | Science Music Video

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BRCA Gene Mutations: Cancer Risk and Genetic Testing Fact Sheet

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A fact sheet about the BRCA1 and BRCA2 genes, what to do if a person tests positive for alterations in one of these genes, and consequences of genetic testing.

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Every person has two copies of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. A person must inherit two copies of the CFTR gene that contain mutations — one copy from each parent — to have cystic fibrosis.

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People who inherit one copy of the CFTR gene that contains a mutation and one normal copy are considered CF carriers. CF carriers do not have the disease but can pass their copy of the defective gene on to their children.

Our Genetic Encyclopedia

Each of our cells contains genetic information that provides the body with coded instructions to make proteins, which determine how the body looks, develops, and works.

Genetic information is stored in chromosomes, which can be thought of as different volumes of our genetic encyclopedia. Humans have 23 pairs of chromosomes. Each pair is made up of one copy of a chromosome from the mother and one from the father.

Most cells in the body have a full copy of the genetic encyclopedia, which includes 23 pairs of chromosomes. However, eggs and sperm have only a single copy of each chromosome, rather than the pairs found in other cells in the body.

Each chromosome is made up of many genes, which are the entries, or topics, in the encyclopedia. The genes supply the body with instructions for making proteins.

All of this genetic information that makes up our genes is in code and stored as a molecule called deoxyribonucleic acid (DNA). The DNA code is made up of letters that spell out the entries of our genetic encyclopedia.

If we all shared 100 percent of our genetic material then we would all be as alike as identical twins are. But not every single letter in the genetic encyclopedia is the same in all of us, which helps to explain why we are not all exactly alike.

How Changes in the CFTR Gene Affect the Body

Different types of changes, or mutations, in our genes affect the body in different ways. Within our genetic encyclopedia, there are small differences in our genes. Sometimes the differences are minor or do not affect a person's health - like two encyclopedia entries that are worded in slightly different ways but still say the same thing. In these cases, people's genes may differ or the protein made by the gene is slightly different - resulting in a different eye color - but the genes and the proteins work correctly.

At other times, the change in a gene may cause the protein to not work or not be made at all. Cystic fibrosis is caused by mutations in the gene that produces the cystic fibrosis transmembrane conductance regulator (CFTR) protein. This protein is responsible for regulating the flow of salt and fluids in and out of the cells in different parts of the body.

In people with CF, mutations in the CFTR gene can disrupt the normal production or functioning of the CFTR protein found in the cells of the lungs and other parts of the body.

Mutations in the CFTR gene cause the CFTR protein to malfunction or not be made at all, leading to a buildup of thick mucus, which in turn leads to persistent lung infections, destruction of the pancreas, and complications in other organs.

Cystic fibrosis is an example of a recessive disease. That means a person must have a mutation in both copies of the CFTR gene to have CF. If someone has a mutation in only one copy of the CFTR gene and the other copy is normal, he or she does not have CF and is a CF carrier. About 10 million people in the United States are CF carriers.

CF carriers can pass their copy of the CFTR gene mutation to their children. Each time two CF carriers have a child together, the chances are:

25 percent (1 in 4) the child will have CF

50 percent (1 in 2) the child will be a carrier but will not have CF

25 percent (1 in 4) the child will not be a carrier of the gene and will not have CF

People with CF can also pass copies of their CFTR gene mutations to their children. If someone with CF has a child with a CF carrier, the chances are:

50 percent (1 in 2) the child will have CF

50 percent (1 in 2) the child will be a carrier but will not have CF

Children of two carriers may be CF carriers like their parents. In a family with four children, it is possible that none of the children, some of the children, or all of the children will have CF. Each baby has the same chance to inherit CFTR mutations from both parents, no matter whether any of the other siblings are carriers or have CF. When someone with CF has children with a CF carrier, the children will either be CF carriers or have CF.

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Every person has two copies of the cystic fibrosis transmembrane conductance regulator (CFTR) gene. A person must inherit two copies of the CFTR gene that contain mutations - one copy from each parent - to have cystic fibrosis.

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Digestive Activity during Germination Flashcard

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Digestive Activity during Germination Flashcard

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AHRI insight #64: How stuff works: 2,4-D, free radicals and monkeys

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Biology Bugbears Pollination and Fertilisation

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Biology Bugbears Female Gamete Formation - Plant Reproduction

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Epigeal germination 'Firetongue' 2 week time lapse

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Runner Bean hypogeal germination time lapse over 24 days

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How to draw diagram of Human Brain easily - step by step | Drawing of Human Brain

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How to draw sensory neuron well labelled and very easy

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Quizlet Flashcards Plant Transport and Storage

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Photosynthesis Explained Simply - Forest Fact Break

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Effect of Light Intensity on the rate of Photosynthesis.

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(OLD VIDEO) Photosynthesis and the Teeny Tiny Pigment Pancakes

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(OLD VIDEO) Plant Structure and Adaptations

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Quizlet Flashcards Plant Structure

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How to draw the skin - Leaving Cert Biology

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Quizlet Flashcards Viruses

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An additional video to assist with revision of rhizopus reproduction. This video does not replace any textbook. Be aware that there is variation in diagrams, so be sure to consult past papers. Not made for monetary gain or intended for commercial use. An optional revision resource aimed towards second level students studying the Irish Leaving Cert Biology Course.

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Quizlet Flashcards Fungi

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Quizlet Flashcards Monera

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Quizlet Flashcards

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Quizlet Flashcards

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Quizlet Flashcards

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Human Reproduction - Male and Female Structure and Hormones

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Human Reproduction - Male and Female Structure and Hormones

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Quizlet Flashcards

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Human Reproduction - Pregnancy, Birth and Breast Feeding

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Human Reproduction - Pregnancy, Birth and Breast Feeding

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Quizlet Flashcards

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Human Reproduction - Infertility and Birth Control

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Human Reproduction - Infertility and Birth Control

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Quizlet Flashcards

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How does your immune system work? - Emma Bryce

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Easily create beautiful interactive video lessons for your students you can integrate right into your LMS. Track students' progress with hassle-free analytics as you flip your classroom!

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amoeba sisters human defence system - Google Search

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Please click here if you are not redirected within a few seconds.

Mar 12, 2020 · Explore the basics about the immune system with The Amoeba Sisters! This video talks about ...
Duration: 8:56
Posted: Mar 12, 2020

Apr 24, 2016 · This is the updated Amoeba Sisters human organ systems video, which provides a brief ...
Duration: 8:22
Posted: Apr 24, 2016

Dec 20, 2018 · This Amoeba Sisters video also briefly introduces the lines of defense in the immune system and ...
Duration: 9:29
Posted: Dec 20, 2018

Missing: human | Must include: human

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From your IP address - Learn more

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amba sisters human defence system - Google Search

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Please click here if you are not redirected within a few seconds. Mar 12, 2020 · Explore the basics about the immune system with The Amoeba Sisters!

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The British Society for Immunology's mission is to support our immunology community in driving scientific discovery and making a positive impact on health.

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What Is The Menstrual Cycle? | Physiology | Biology | FuseSchool

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Fertility Doctor and IVF Specialist Sydney

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ivf embryo developing over 5 days by fertility Dr Raewyn Teirney

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Immune system questions (practice) | Khan Academy

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A few harmful microbes, for example less than 1% of bacteria, can invade our body (the host) and make us ill. Microbes cause infectious diseases such as flu and measles.

There is also strong evidence that microbes may contribute to many non-infectious chronic diseases such as some forms of cancer and coronary heart disease. Different diseases are caused by different types of micro-organisms. Microbes that cause disease are called pathogens.

It is important to remember that:

A pathogen is a micro-organism that has the potential to cause disease.

An infection is the invasion and multiplication of pathogenic microbes in an individual or population.

Disease is when the infection causes damage to the individual's vital functions or systems.

An infection does not always result in disease!

To cause an infection, microbes must enter our bodies. The site at which they enter is known as the portal of entry.

Microbes can enter the body through the four sites listed below:

Respiratory tract (mouth and nose) e.g. influenza virus which causes the flu.

Gastrointestinal tract (mouth oral cavity) e.g. Vibrio cholerae which causes cholera.

Urogenital tract e.g. Escherichia coli which causes cystitis.

Breaks in the skin surface e.g. Clostridium tetani which causes tetanus.

To make us ill microbes have to:

reach their target site in the body;

attach to the target site they are trying to infect so that they are not dislodged;

multiply rapidly;

obtain their nutrients from the host;

avoid and survive attack by the host's immune system.

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Microbes and disease | Microbes and the human body

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A few harmful microbes, for example less than 1% of bacteria, can invade our body (the host) and make us ill. Microbes cause infectious diseases such as flu and measles. There is also strong evidence that microbes may contribute to many non-infectious chronic diseases such as some forms of cancer and coronary heart disease.

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Reviewed By: Stuart I. Henochowicz, MD, FACP, Clinical Professor of Medicine, Division of Allergy, Immunology, and Rheumatology, Georgetown University Medical School, Washington, DC. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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These amoeba-like cells are a type of phagocyte called macrophages. They're scavenger cells that can form tentacles called pseudopods to surround and ingest foreign cells. Once swallowed, the cells are walled off and destroyed by a bag of digestive enzymes.

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Excretion - ADH and Homeostasis - GCSE Biology (9-1)

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Thyroxine | Hormones & Homeostasis | GCSE Biology (9-1) | kayscience.com

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Thyroid Gland, Hormones and Thyroid Problems, Animation

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Easily create beautiful interactive video lessons for your students you can integrate right into your LMS. Track students' progress with hassle-free analytics as you flip your classroom!

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The endocrine system is a series of glands that produce and secrete hormones that the body uses for a wide range of functions. Sometimes these hormones get out of balance, and can lead to problems like diabetes, weight gain or loss, infertility, weak bones, and other problems. Learn what endocrinologist have to say about how to keep your body in balance.