Download presentations on the theme of the cell and its structure in biology for all classes

The cell is part of the structure of living organisms. It is able to exist and develop independently. Every living organism is made up of cells. It can be an organism of both a person and an animal, plant or fungus. Growth, reproduction and development are the main functions that the cell provides. In our time, it is not difficult for people to examine a cell and determine its composition and not only.

Download presentation

The cell is surrounded by a membrane that determines the shape of the cell, and it also "filters" the substances that enter inside. From there, unnecessary substances are removed. The next layer in the cell structure is the cytoplasm. This substance is semi-solid, inside which various nutrients move. Well, the nucleus is located inside, with the exception of cases when, for some reason, the nucleus disappears (for example, in cells that are located in the liver). The nucleus plays a very important role in the structure of the cell. It contains chromosomes, which are formed from DNA.

Download presentation

DNA is a molecule that is able to store and transmit from generation to generation, as well as implement the program of genetic development and the vital activity of organisms. It is found inside the nucleus, in chromosomes, and also in some organelles that are found in cells. DNA is a molecule made up of repeating blocks.

Download presentation

All living organisms on Earth are divided into cells. The basic concept of cell theory is that cells are the basic structural unit for all organisms. Cells are small cells that hold the biological equipment necessary for an organism to live and develop. Living beings can be single-celled or they can be very complex, such as the human body.

Download presentation

There are smaller pieces that make up cells, such as macromolecules and organelles. Protein is an example of a macromolecule while mitochondria is an example of an organelle. Cells can also coalesce to form larger structures. They cluster together to form the tissues of the stomach and eventually the entire digestive system. In the same way that atoms are the basic unit of matter, cells are the basic unit for biology and organisms.

Download presentation

According to the cell theory, cells are the basic living unit in biology. Whether you are one cell or a blue whale with trillions of cells, you are still cells. All cellular contents are located within the cell membrane. When you think of a membrane, think of it as a big plastic bag with some tiny holes. This bag keeps all cell parts and fluids inside the cell and keeps any nasties out of the cell. The holes in the membrane serve to ensure that nutrients enter it and waste products are removed.

Download presentation

Presentation on the topic "Structure of the cell" in biology in powerpoint format. The purpose of this presentation for schoolchildren is to consider the structure of organelles and determine their functions. Presentation author: biology teacher, Opaleva Elena Sergeevna.

Fragments from the presentation

Who opened the cage

Robert Hooke 1663

What is the name of the science of the cell

Cytology

Organelles are called structures constantly present in the cell that perform strictly

certain functions.

Membrane

golgi complex
Lysosomes
mitochondria

Non-membrane

ribosomes
cytoskeleton
cell center

plasma membrane

STRUCTURE

Bilayer of lipids with proteins in it, limiting the cell

FUNCTIONS

Barrier - protects the internal environment of the cell from the external
Nutrient - absorbs nutrients in the form of droplets (pinocytosis), particles (phagocytosis) or by diffusion

Conclusion

The functions of organelles are complex and diverse. They play the same role for the cell as organs do for the whole organism.

9th grade student Rulev Igor

The presentation can be used in lessons in grades 9, 10, 11

Download:

Preview:

To use the preview of presentations, create a Google account (account) and sign in: https://accounts.google.com

Slides captions:

Presentation on the topic: the structure of the cell The presentation was made by a student of the 9th grade of school No.

What is a cell made of? The cell can be divided into 11 parts: 1) Membrane 2) Nucleus 3) Cytoplasm 4) Cell center 5) Ribosomes 6) EPS 7) Golgi complex 8) Lysosomes 9) Cell inclusions 10) Mitochondria 11) Plastids

Membrane It is a thin (about 7.5 nm2 thick) three-layer cell membrane, visible only in an electron microscope. The two extreme layers of the membrane are composed of proteins, and the middle layer is formed by fat-like substances. The membrane has very small pores, due to which it easily passes some substances and retains others. The membrane takes part in phagocytosis (the capture of solid particles by the cell) and in pinocytosis (the capture by the cell of liquid droplets with substances dissolved in it).

Nucleus The nucleus of a nondividing cell has a nuclear envelope. It consists of two three-layer membranes. The outer membrane is connected through the endoplasmic reticulum to the cell membrane. Through this entire system, there is a constant exchange of substances between the cytoplasm, the nucleus and the environment surrounding the cell. In addition, there are pores in the nuclear membrane through which the nucleus also communicates with the cytoplasm. Inside the nucleus is filled with nuclear juice, which contains lumps of chromatin, the nucleolus and ribosomes. Chromatin is made up of protein and DNA. This is the material substrate that, before cell division, is formed into chromosomes visible in a light microscope.

Cytoplasm Cytoplasm is a complex colloidal system. Its structure: transparent semi-liquid solution and structural formations. The structural formations of the cytoplasm common to all cells are: mitochondria, endoplasmic reticulum, Golgi complex and ribosomes. All of them, together with the nucleus, are the centers of certain biochemical processes that together make up the metabolism and energy in the cell. These processes are extremely diverse and proceed simultaneously in a microscopically small volume of the cell.

The cell center The cell center is a formation that has so far been described only in the cells of animals and lower plants. It consists of two centrioles, the structure of each of which is a cylinder up to 1 micron in size. Centrioles play an important role in mitotic cell division. In addition to the described permanent structural formations, certain inclusions periodically appear in the cytoplasm of various cells. These are fat droplets, starch grains, protein crystals of a special form (aleurone grains), etc. Such inclusions are found in large numbers in the cells of storage tissues. However, in cells of other tissues, such inclusions can exist as a temporary reserve of nutrients.

Ribosomes Ribosomes are found both in the cytoplasm of the cell and in its nucleus. These are the smallest grains with a diameter of about 15-20 nm, which makes them invisible in a light microscope. In the cytoplasm, the bulk of the ribosomes is concentrated on the surface of the tubules of the rough endoplasmic reticulum. The function of ribosomes is the most responsible for the life of the cell and the organism in the whole process - in the synthesis of proteins.

EPS (endoplasmic reticulum) The endoplasmic reticulum is a multi-branched protrusion of the outer membrane of the cell. The membranes of the endoplasmic reticulum are usually arranged in pairs, and tubules are formed between them, which can expand into larger cavities filled with biosynthetic products. Around the nucleus, the membranes that make up the endoplasmic reticulum directly pass into the outer membrane of the nucleus. Thus, the endoplasmic reticulum links together all parts of the cell. In a light microscope, when examining the structure of the cell, the endoplasmic reticulum is not visible.

Golgi complex The Golgi complex (Fig. 2, 5) was initially found only in animal cells. Recently, however, similar structures have been found in plant cells. The structure of the structure of the Golgi complex is close to the structural formations of the endoplasmic reticulum: these are tubules, cavities and vesicles of various shapes formed by three-layer membranes. In addition, the Golgi complex includes rather large vacuoles. They accumulate some products of synthesis, primarily enzymes and hormones. During certain periods of cell life, these reserved substances can be removed from the cell through the endoplasmic reticulum and are involved in the metabolic processes of the body as a whole.

Lysosomes This is a very variegated class of vesicles 0.1-0.4 microns in size, limited by a single membrane (about 7 nm thick), with heterogeneous contents inside. They are formed due to the activity of the endoplasmic reticulum and the Golgi apparatus and in this respect resemble secretory vacuoles. Their main role is participation in the processes of intracellular cleavage of both exogenous and endogenous biological macromolecules. A characteristic feature of lysosomes is that they contain about 40 hydrolytic enzymes: proteinases, nucleases, phosphatases, glycosidases, etc., the optimum of which is carried out at pH5. In lysosomes, the acidic value of the environment is created due to the presence in their membranes of a proton "pump" that consumes the energy of ATP.

Cell inclusions Cell inclusions Cell inclusions are all structures of the cytoplasm of a cell. Usually V. to. subdivide into 3 groups: the constants, or the organelles which are carrying out the general functions of a cell (for example, Mitochondria, Golgi a complex, Chloroplasts); temporary, or paraplasmic, formations that appear and disappear in the process of metabolism (for example, secretory granules, nutrients, fat, starch, etc.); special, or metaplasmic, formations that are present in some specialized cells, where they perform particular functions, for example, contractions (myofibrils of muscle cells), supports (tonofibrils in epidermal cells).

Mitochondria Mitochondria are the energy centers of the cell. These are very small bodies, but clearly visible in a light microscope (length 0.2-7.0 microns). They are located in the cytoplasm and vary greatly in shape and number in different cells. The liquid content of mitochondria is enclosed in two three-layer shells, each of which has the same structure as the outer membrane of the cell. The inner shell of the mitochondrion forms numerous invaginations and incomplete partitions inside the body of the mitochondrion. These invaginations are called cristae.

Plastids plastids exist in three forms: green chloroplasts, red-orange-yellow chromoplasts, and colorless leucoplasts. Leukoplasts, under certain conditions, can turn into chloroplasts, and chloroplasts, in turn, can become chromoplasts. Chloroplasts are small bodies of a rather varied shape, always green due to the presence of chlorophyll. The structure of chloroplasts in the cell: they have an internal structure that ensures the maximum development of free surfaces. These surfaces are created by numerous thin plates, the clusters of which are located inside the chloroplast. From the surface, the chloroplast, like other structural elements of the cytoplasm, is covered with a double membrane. Each of them, in turn, is three-layered, like the outer membrane of the cell. Chromoplasts are similar in nature to chloroplasts, but contain yellow, orange, and other pigments close to chlorophyll, which determine the color of fruits and flowers in plants. This occurs both by increasing the number of cells through division, and by increasing the size of the cells themselves. In this case, most of the structure of the cell body is occupied by vacuoles. Vacuoles are enlarged tubules in the endoplasmic reticulum filled with cell sap.

The structures of the cells of representatives of different kingdoms of organisms have characteristic differences. Trait Cells Mushrooms Plants Animals Cell wall Mainly made of chitin From cellulose No Large vacuole Yes Yes No Chloroplasts No Yes No Feeding method Heterotrophic Autotrophic Heterotrophic Centrioles Rarely occurs Only in some mosses and ferns Has Reserve nutrient carbohydrate Glycogen Starch Glycogen Rulev Igor 9G

1 of 9

Presentation on the topic: General structure of the cell

slide number 1

Description of the slide:

General structure of the cell. The cell is the basic unit of life on Earth. The cell is the structural and functional unit of the living. It is characterized by all the signs of living organisms: metabolism and energy, growth, reproduction. Cells vary in shape, size, and function. But they have the same chemical composition. Chemical composition. Of all the known chemical elements, about 60 are found in living organisms. These elements are called biogens. They can be divided into three groups: 1.Macroelements (98% of the total composition): O, C, H, N, P, Ca/ 2.Microelements (about 1%): S, K, Na, Cl, Fe. 3.Ultra micronutrients (less than 0.01% or trace amounts): Mn, I, F, B, etc.

slide number 2

Description of the slide:

Nucleus. The nucleus is the center of regulation of cell activity. The nucleus is separated from the cytoplasm by a double nuclear membrane penetrated by pores. Inside it is filled with karyoplasm, which contains DNA molecules. The nuclear apparatus regulates all the life processes of the cell, ensures the transmission of hereditary information. Here the synthesis of DNA, RNA, ribosomes takes place. Often in the nucleus you can see one or more dark rounded formations - nucleoli, in which ribosomes form and accumulate. In the nucleus, DNA molecules are not visible because they are in the form of thin strands of chromatin. During division, DNA is highly spiralized, thickened, forming complexes with protein and turning into clearly visible chromosome structures.

slide number 3

Description of the slide:

outer cell membrane. The plasma membrane is a bilayer of lipids and proteins. The cell membrane surrounds each cell, separating it from the external environment. The outer membrane protects the inner contents of the cell - the cytoplasm and nucleus - from damage, maintains a constant shape of the cell, provides communication between cells, selectively passes the necessary substances into the cell and removes metabolic products from the cell. The structure of the membrane in all cells is the same. Its thickness is approximately 8 nm, and therefore it is impossible to see the membrane in a light microscope. Some proteins are located on the surface of the lipid layer, while others penetrate both layers of lipids through and through. Special proteins form the thinnest channels through which K, Na, Ca ions of small size can pass into or out of the cell. However, larger particles cannot pass through the membrane channels. Molecules of nutrients - proteins, carbohydrates, lipids - enter the cell with the help of phagocytosis and pinocytosis.

slide number 4

Description of the slide:

Endoplasmic reticulum. EPS is a single-membrane system of tubules, tubules, cisterns that permeates the entire cytoplasm. It is involved in metabolism: it synthesizes lipids for the outer membrane of the cell and for its own membrane, provides for the transport of substances between cell organelles, serves as a “piggy bank” of substances and a place for their isolation. There are smooth and granular EPS. Granular carries numerous ribosomes on the outer surface. Protein is synthesized on it, and lipids are synthesized on the smooth surface.

slide number 5

Description of the slide:

Golgi apparatus. A significant part of the substances synthesized by the cell through the EPS channels enters special cavities, limited from the cytoplasm by a membrane. These cavities, stacked in a kind of stacks, "tanks", are called the Golgi complex. Here, the substances necessary for the cell itself are “packed into membrane vesicles and carried through the cytoplasm.

slide number 6

Description of the slide:

Lysosomes. Lysosome is a small vesicle with a diameter of only 0.5 - 1.0 microns, containing a large set of enzymes that can destroy food substances. One lysosome can contain 30-50 different enzymes. Lysosomes are surrounded by a membrane that can withstand the effects of these enzymes. Lysosomes are formed in the Golgi complex. It is in this structure that the synthesized digestive enzymes are accumulated, and then the smallest vesicles, lysosomes, depart from the tanks of the Golgi complex into the cytoplasm. Sometimes lysosomes destroy the very cell in which they formed

slide number 7

Description of the slide:

Mitochondria. Mitochondria are also located in the cytoplasm - the energy organelles of cells. The shape of mitochondria is different - they can be oval, round, rod-shaped. Their diameter is about 1 micron, and their length is up to 7 - 10 microns. Mitochondria are covered with two membranes: the outer membrane is smooth, and the inner one has numerous folds and protrusions - cristae. Enzymes are built into the membrane of the cristae. The number of mitochondria in a cell depends on its age: there are much more mitochondria in young cells than in aging ones. Mitochondria contain their own DNA and can reproduce on their own.

slide number 8

Description of the slide:

Orgonoids of movement. Many cells are capable of movement. Some of these organisms move with the help of special organelles of movement - cilia and flagella. The flagella are relatively long. The cilia are much shorter, about 10–15 µm. However, the internal structure of cilia and flagella is the same: they are formed by microtubules. At the base of each cilium or flagellum lies a basal body, which strengthens them in the cytoplasm of the cell.

slide number 9

Description of the slide:

Cell inclusions. In addition to the obligatory presence of organelles, in the cell there are formations that appear, then disappear, depending on its state. These formations are called cellular inclusions. Most often, cell inclusions are located in the cytoplasm and are nutrients or granules of substances synthesized by this cell. These can be small drops of fat, starch or glycogen granules, less often - protein granules, salt crystals.

To use the preview of presentations, create a Google account (account) and sign in: https://accounts.google.com

Slides captions:

CELL STRUCTURE - BASIC ORGANOSES Biology teacher of the secondary school of the sanatorium "Druzhba" Holomeeva Anna Aleksandrovna

PURPOSE OF THE LESSON: Consider the structure of organelles and determine their functions

So where do we start, Mr Cyres? asked Pencroff the next morning. From the very beginning,” said Cyrus Smith. Jules Verne

Who discovered the cell Robert Hooke 1663 What is the name of the science of the cell Cytology

Organelles are structures that are constantly present in the cell and perform strictly defined functions.

Organelles Membrane nucleus EPS Golgi complex Lysosomes Mitochondria Non-membrane ribosomes Cytoskeleton Cell center

PLASMATIC MEMBRANE STRUCTURE Bilayer of lipids with proteins contained in it, which limits the cell

Cell membrane functions: separation of the contents of the cell and the external environment; regulation of metabolism between the cell and the environment; place of some biochemical reactions (including photosynthesis); association of cells into tissues. The most important property of the plasma membrane is semipermeability. Glucose, amino acids, fatty acids and ions slowly diffuse through it.

MEMBRANE STRUCTURE

Endocytosis

Exocytosis

Cytoplasm It is a watery substance - hyaloplasm (90% water), in which various organelles are located, as well as inclusions (lumps of glycogen, fat drops, starch crystals. Glycolysis, synthesis of fatty acids, nucleotides and other substances occurs in the hyaloplasm. It is a dynamic structure. Organelles move, and sometimes cyclosis is also noticeable - an active movement in which the entire protoplasm is involved.

CYTOPLASMA STRUCTURE Internal environment of the cell FUNCTIONS Ensures the activity of the cell as a single system

NUCLEUS STRUCTURE A closed reservoir surrounded by two layers of membranes pierced by nuclear pores. Inside is the nuclear sap, chromosomes (made of DNA and protein) and nucleoli (made of RNA and protein) FUNCTIONS Storage of genetic information and RNA synthesis

Nucleus In size (10–20 µm), being the largest of the organelles. The most important function of the nucleus is the preservation of genetic information. It is covered with a nuclear envelope, which consists of two membranes: outer and inner, having the same structure as the plasma membrane. Between them is a narrow space filled with a semi-liquid substance. Through many pores in the nuclear envelope, the exchange of substances between the nucleus and the cytoplasm takes place (in particular, the release of mRNA into the cytoplasm). The outer membrane is often littered with ribosomes. Substances from the cytoplasm enter the karyoplasm (nuclear juice). Contains chromatin - a substance that carries DNA, and nucleoli - rounded structures inside the nucleus, in which the formation of ribosomes occurs. The totality of chromosomes contained in chromatin is called a chromosome set.

MITOCHONDRIA

MITOCHONDRIA STRUCTURE Oval bodies consisting of two layers of the membrane: external (smooth) and internal (forms folds - cristae) FUNCTIONS ATP synthesis during respiration, capable of independent division

GOLGI COMPLEX

GOLGI COMPLEX STRUCTURE Complex of closed membrane reservoirs located near the nucleus FUNCTIONS Synthesis of fats and polysaccharides, transport of substances and their secretion, formation of lysosomes

The endoplasmic reticulum is a network of membranes that span the cytoplasm. connects organelles with each other, along it the transport of nutrients occurs. Smooth EPS has the form of tubules, the walls of which are made of a membrane. It synthesizes lipids and carbohydrates. There are many ribosomes on the membranes of the channels and cavities of the granular ER; this type of network is involved in protein synthesis.

LYSOSOME

LYSOSOMS STRUCTURE Closed membrane bodies containing enzymes that uncouple various substances of the cell FUNCTIONS Digestion of nutrients entering the cell, self-destruction of dying cells

Ribosomes are small (15–20 nm in diameter) organelles consisting of rRNA and polypeptides. The most important function is protein synthesis. Their number in the cell is very large: thousands and tens of thousands. Ribosomes can be associated with the endoplasmic reticulum or be in a free state. In the process of synthesis, many ribosomes usually simultaneously participate, united in chains, called polyribosomes (polysomes).

Microtubules Hollow cylindrical with a diameter of about 25 nm, the length can reach several micrometers. The walls of microtubules are made up of the protein tubulin. Centrioles Found in the cells of animals and lower plants - small hollow cylinders tenths of a micrometer long, built from 27 microtubules. During cell division, they form a spindle of division. The basal bodies are identical in structure to the centrioles contained in the flagella and cilia. These organelles cause flagella to beat. Another function of microtubules is the transport of nutrients. Microtubules are fairly rigid structures that support the shape of the cell, forming a kind of cytoskeleton. Another form of organelles is also associated with support and movement - microfilaments - thin protein filaments with a diameter of 5–7 nm.

All organelles found in animal cells are present in plant cells (with the exception of centrioles). The cell walls of plants are made up of cellulose, which forms microfibrils. In the cells of treelike plants, the layers of cellulose are impregnated with lignin, which gives them additional rigidity. They serve as a support for plants, protect cells from rupture, determine the shape of the cell, play an important role in the transport of water and nutrients from cell to cell. Neighboring cells are connected to each other by plasmodesmata passing through the small pores of the cell walls. A vacuole is a fluid-filled membrane sac. In animal cells, small vacuoles can be observed that perform phagocytic, digestive, contractile and other functions. Plant cells have one large central vacuole containing cell sap. It is a concentrated solution of sugars, mineral salts, organic acids, pigments and other substances. Accumulate water, may contain coloring pigments, protective substances (for example, tannins), hydrolytic enzymes that cause cell autolysis, waste products, reserve nutrients.

Plastids: chloroplasts, chromoplasts, leucoplasts

CHLOROPLASTS

ANIMAL AND PLANT CELL

Plant cell Animal cell Similarity The presence of a plasma membrane. Cytoplasm Nuclei with nucleolus Chromosomes Endoplasmic reticulum Mitochondria Ribosomes Golgi complex Differences There is a central vacuole There are plastids No lysosomes The cell is covered with a cellulose cell wall on the outside No central vacuole No plastids There are lysosomes There is no cell wall, it is covered with glycocalex on the outside

CONCLUSION: The functions of organelles are complex and diverse. They play the same role for the cell as organs do for the whole organism.

Control summary of the material List the membrane organelles of the cell.

Cytoplasmic membrane, endoplasmic reticulum, Golgi complex, mitochondria, lysosomes, plastids

2. What chemicals form CM?

Proteins and lipids

What organelle is the energy station of the cell?

Mitochondria

What is the function of lysosomes?

Intracellular digestion and breakdown of substances

What is the function of the Golgi complex?

Synthesis of lipids and carbohydrates, secretion of proteins, carbohydrates and lipids

The value of ribosomes for the cell

protein synthesis

What organelles make up the cytoskeleton of a cell?

microtubules

What is inclusion?

Non-permanent structures where the supply of nutrients is located: fat, starch, protein

EPS value?

Rough ER - protein synthesis and transport Smooth ER - lipid synthesis and transport

What separates the nucleus from the cytoplasm?

bilayer nuclear membrane.

Name non-membrane organelles

Ribosomes, cell center, microtubules.

Homework: Know the structure of organelles and their functions Compose a crossword puzzle on the topic "Structure of the cell" Answer the questions in the paragraph in writing

List of sources used: Open Biology 2.6. LLC "Fizikon" 2000-2005.