When the word ‘cell’ comes up in a biology textbook, you probably expect the biology textbook to be about cells.
But the words ‘biology’ and ‘cells’ are more often used to describe organisms, and biology is about a lot of things.
For instance, we often use the word “cell” to describe a single cell, but we also use “cells” to refer to the whole organism.
Cells can carry genes, they can make proteins, they form mitochondria, and they can metabolise food.
So what exactly are cells?
How do we know what they are?
In a way, they are a kind of ‘cognate’ of the term ‘animal’.
That’s because the two terms are related, meaning that the words refer to something that is similar to what it is.
When we say animal, we mean the animal that shares the characteristics of an animal: it has a body, a tail, and the like.
Animals can have a very different shape, or even different colour, but they all share the same general traits.
But animals don’t have ‘cells’.
For instance: they don’t produce hormones.
They don’t eat or digest food.
And they don´t reproduce, which is why they’re called “living organisms”.
If animals can’t reproduce, how are they related to other animals?
The idea of a ‘living’ organism is one of the main reasons animals are called “animals”.
Animals are related to each other because they’re related to plants and plants are related (at least superficially) to each of the three other main living organisms.
There are other ways to say “animal”.
Animals have a social life.
They have a sense of identity and they form social groups that form communities.
And animals can communicate with each other by vocalising.
But these are different aspects of the same concept.
The real meaning of animal is “a person or group of people that share characteristics of animals”.
And this is why we often think of animals as “animated” rather than “living”.
The concept of “animal” can also be used to refer, for instance, to the cells that make up the skin and bones of animals.
In the case of bones, the term “bone” is used to mean a group of cells that form the fibrous material that is the bone.
These cells are called cartilage cells.
The idea is that they are related because they make up most of the fibres of the skin, and it is through these cells that bones are made.
But that’s not the whole story.
When it comes to the properties of cells, animals are different from plants.
Plants produce the chemicals called vitamins.
These chemicals can be broken down into other chemicals.
Some of the other chemicals that are produced are called proteins.
So the idea that plants produce chemicals that help make plants is a general idea.
But when it comes time to discuss the properties and functions of plants, plants have a special word to refer them to: photosynthetic organisms.
In this context, plants can be compared to animals, and we can think of them as ‘living organisms’.
But animals are animals because they reproduce.
Animals reproduce by laying eggs.
Animals lay eggs by releasing sperm.
When a fertilised egg is released, the fertilised sperm contains some DNA and a gene.
The genes are made by a protein called an RNA, and those genes help the animal to develop.
Animals don’t do that, so they can’t produce genes.
They can’t make proteins either.
So, the idea is this: animals are living organisms because they have a body that is made of cells and proteins.
Animals have different properties from plants, because they produce proteins.
Plants, in contrast, produce chemicals called hormones.
These hormones are produced by certain kinds of animals that live in groups and can communicate.
Animals cannot reproduce because they are not animals.
And in some cases, animals cannot communicate because they don�t have the same kind of cell type.
When an animal is born, it can’t survive without a parent.
But how do animals reproduce?
In plants, we have two kinds of plants: leaves and stems.
Leaves are part of the plant, and are therefore able to grow and become branches.
Stems are not part of a plant and can be used for other things.
So when an animal comes into contact with a stem, the animal passes along genes that tell it which stem to use.
These genes then get passed on to the next generation of animals, so that the next animal in the line will have a better chance of reproducing.
This is called inbreeding.
Animals in general are unable to reproduce by themselves.
Instead, animals have an all-around group of parents.
But there are some animals that are special in this respect.
We have the pig, for example.
Pigs are one of only two animals that can breed themselves.
They get a genetic mutation that makes them unable to produce any offspring