Cells are the basic "building blocks" of life. All organisms (multicellular and single-celled) possess them; the animal ones have numerous differences from the vegetable ones, for example they do not have chloroplasts, vacuoles and cell walls. By studying the organelles of the animal cell and learning their general shape, you can easily draw the cell itself.
Steps
Part 1 of 2: Cell Membrane and Nucleus
Step 1. Draw a simple oval or circle for the membrane
That of animal cells does not define a perfect circumference, so you can draw an oblong shape or an imprecise circle; the important thing is that there are no sharp edges. Also remember that it is not a rigid structure like the wall of plant cells, but it allows molecules to enter and exit.
Make the circle large enough that you can draw all the organelles inside it with good definition
Step 2. Add the pinocytosis vesicles
Detailed models of animal cells also predict these structures within the membrane; they resemble small bulbous bubbles that push on the outer portion of the membrane without breaking it.
During pinocytosis, the cell membrane envelops the extracellular fluid (that which is outside the cell) and then draws it inside for digestion or absorption; this is the reason why you have to draw the vesicles as rounded formations surrounded by the membrane
Step 3. Draw two circles to define the core
It is one of the largest structures in the cell; to draw it you need to add two circles, the larger one occupies about 10% of the cellular space and contains the slightly smaller one.
- The nucleus of the animal cell has pores called nuclear pores; to represent them, delete two or three small sections of each circle, then connect the outer segments with the inner ones. Eventually you should get curved cylinders that almost don't touch.
- The outer portion is called the nuclear envelope. To draw a very detailed model, add several points on the outside of the nuclear membrane to represent the ribosomes that are attached to it.
Step 4. Draw a small shaded circle for the nucleolus
This is the central structure of the nucleus and which produces the ribosomal subunits which then combine in other sectors of the cell; you can represent it with a small shaded circle.
Step 5. Add a scribble to indicate chromatin
The rest of the nucleus space should appear as a single large squiggle representing chromatin made up of DNA and proteins.
Part 2 of 2: Cellular Organelles
Step 1. Trace the rounded sticks to draw the mitochondria
These represent the "powerhouse" of the cell and you can define them as two or three large oval sticks within the cell space but outside the nucleus. Each mitochondrion should contain a closed structure with many ridges and folds; these are the mitochondrial crests (the inner membrane folded back on itself) which in this way provide greater contact surface to carry out the processes of the organelle.
Leave a space between the outer oval perimeter (outer membrane) and the inner membrane
Step 2. Add finger-like structures representing the endoplasmic reticulum
It starts at one edge of the nuclear membrane and draws a long figure extending into the cell space with several "fingers" pointing in various directions before rejoining the nucleus. All this complex structure forms the endoplasmic reticulum; make it quite large, as it typically takes up to 10% of the entire cell volume.
Animal cells have both smooth and rough endoplasmic reticulum. To draw the latter, define dots on the outer portion of the "fingers" on one side of the structure; the dots represent ribosomes
Step 3. Draw a series of dumbbell-like shapes to represent the Golgi apparatus
Draw a series of three oval structures that resemble gym dumbbells composed of a central oval "barbell" with two balls at the ends. As you move away from the nucleus and get closer to the cell membrane, each "dumbbell" should be slightly larger than the one before it.
- The Golgi apparatus processes, packages and exports the complex molecules in the cell and outside it using vesicles that you can represent by drawing small bubbles around the organelle itself.
- Write the initial of the word "Golgi" in capital letters, because it is the surname of the Italian scientist and doctor who discovered the structure.
Step 4. Draw two small rectangles perpendicular to each other to define the centrioles
These organelles contribute to cell division; they are very close but not in contact with the core. Draw them as two small rectangles orthogonal to each other next to the core.
The centrioles are organelles in pairs, which is why you need to draw two rectangles
Step 5. Add another small circle for the lysosome
In practice, it performs the function of "dump" of the cell and degrades the waste material to reuse it. You can represent it as a small circumference close to the cell edge, then add many dots that define digestive enzymes (lysosomal hydrolytic enzymes).
You can place the lysosome near the Golgi apparatus, as it often seems to "blossom" from the Golgi itself
Step 6. Draw dots inside the cell space but outside the organelles to represent ribosomes
These structures float in the cytosol, the cellular fluid that is inside the membrane but outside the organelles; you can represent these ribosomes as many dots scattered a little everywhere.
- If you have to respect a color code for the design, use the same dye for the ribosomes attached to the nuclear membrane and the rough endoplasmic reticulum.
- The intracellular fluid is indifferently called cytosol or cytoplasm, while that present in the nucleus is called nucleoplasm.
Advice
- In class or home assignments, most teachers ask to identify the parts of the cell by writing their name; get used to labeling each structure and organelle.
- If you want to draw particular cells, such as an amoeba or a paramecium, first study them carefully; generally, they are equipped with other structures such as flagella, cilia, pseudopodia and so on.
- If you are making a three-dimensional model, use papier mache.
