Dna replication
digestive enzymes
self-replicating organelle
semi-permeable membrane
protein molecules
energy generation
cell secretion
membrane-bound system
genetic information
lipid membrane
synthesis of proteins
nutritive and protective environment
viscous cell substance
defining boundary
phospholipid bilayer
Ex. 5. Read and translate the following sentences:
Cell organelles are adapted for carrying out one or more vital functions.
Organelle is a specialized subunit which is enclosed within its own lipid membrane.
The nucleus houses the cell's chromosomes, regulates synthesis of proteins, stores and transmits genetic information about the cell.
Plasma membrane acts as a cell's defining boundary and separates the interior of the cell from its surrounding environment.
The Golgi apparatus takes part in modifying, sorting, and packaging of macromolecules.
Lysosomes digest macromolecules, old unneeded organelles, proteins or microbes that have invaded the cytoplasm.
Ex. 6. Read the text, entitle it and write out one main function of each organelle:
The human body contains many different organs, such as the heart, lung, and kidney and each organ performs a different function. Cells also have a set of "little organs," called organelles that are adapted for carrying out one or more vital functions. Organelle is a specialized subunit within a cell that has a specific function, and is separately enclosed within its own lipid membrane. There are many types of organelles, particularly in the cells of higher organisms. The most important organelles of the cell are the nucleus, cytoplasm, plasma membrane, mitochondria, endoplasmic reticulum, Golgi apparatus, ribosomes and lysosomes.
The nucleus is a cell’s information center. It houses the cell's chromosomes, and is the place where almost all DNA replication and RNA synthesis occur. It stores genetic information about the cell and transmits it during cell division. It also regulates synthesis of proteins necessary for normal functioning of the cell. The nucleus is spherical in shape and separated from the cytoplasm by a double membrane called the nuclear envelope. The nuclear envelope isolates and protects a cell's genetic material from various molecules that could accidentally damage its structure or interfere with its processing.
The nucleus of a cell is surrounded by cytoplasm. It is a viscous cell substance that takes up most of the cell volume. It contains proteins, amino acids, salts and water and acts as nutritive and protective environment for other organelles of the cell. The cytoplasm of a cell is surrounded by a plasma membrane, a cell's defining boundary. This membrane separates the interior of the cell from its surrounding environment and regulates what moves in and out of the cell. The plasma membrane consists of a double layer of lipids (sometimes it is called a phospholipid bilayer) and a variety of protein molecules that act as channels and pumps moving different molecules into and out of the cell. Due to its structure the membrane is considered to be 'semi-permeable', it can either take in different substances or not to take at all.
Mitochondria represent energy center of the cell. They are self-replicating organelles that occur in various numbers, shapes, and sizes in the cytoplasm. Mitochondria play an important role in generating energy. They add oxygen to food to produce energy.
The endoplasmic reticulum (ER) serves many general functions, including the transport of synthesized proteins. It is the transport network for molecules targeted for specific destinations. The ER has two forms: the rough ER, which has ribosomes on its surface, and the smooth ER, which lacks them.
Also the Golgi apparatus is an organelle that takes part in modifying, sorting, and packaging of macromolecules for cell secretion or for use within the cell. It modifies proteins delivered from the rough endoplasmic reticulum, transports lipids around the cell and creates lysosomes. In this respect it can be thought of as similar to a post office; it packages and labels items and then sends them to different parts of the cell.
The ribosome is a large complex, composed of many molecules. They play an important role in protein biosynthesis, the process of transforming RNA into protein.
Lysosomes are organelles that contain digestive enzymes. They digest macromolecules, old unneeded organelles, proteins or microbes that have invaded the cytoplasm. The cell could not house such destructive enzymes if they were not contained in a membrane-bound system. These organelles are often called a "suicide bag" because of their ability to destroy the cell.
Ex. 7. Answer the questions:
What is organelle? What can it be compared to?
What organelles does the cell have? What are their main functions?
What is nucleus? How does it look like?
What is the function of nuclear envelope?
What does the plasma membrane consists of?
Why is the plasma membrane 'semi-permeable'?
How do mitochondria generate energy?
What are the two forms of endoplasmic reticulum? What is the difference between them?
What is the Golgi apparatus compared to? Why?
10) How can the cell house destructive enzymes within it?
Ex. 8. Say whether the following statements are true or false:
The cell contains many different organs.
Organelle is a "little organ" of the cell that has a specific function.
The nucleus is round in shape and separated from the cytoplasm by a double membrane.
The nucleus contains proteins, amino acids, salts and water.
The cytoplasm of a cell separates the interior of the cell from its surrounding environment.
Phospholipid bilayer is considered to be 'semi-permeable'.
Lipids of the plasma membrane act as channels and pumps moving different molecules into and out of the cell.
The Golgi apparatus is similar to a post office; it packages and labels items and then sends them to different parts of the cell.
Proteins and microbes that have invaded the cytoplasm digest macromolecules and old unneeded organelles.
10) The cell can house destructive enzymes because they are contained in a membrane-bound system.
Ex. 9. Make up sentences:
about, cell, the, genetic, it, stores, the, during, cell, and, transmits, nucleus, information, division.
destinations, targeted, the, the, molecules, transport, endoplasmic, specific, network, for, for, reticulum, is.
system, are, contain, enzymes, are, included, organelles, into, a, lysosomes, which, digestive, membrane-bound, that.
Ex. 10. Describe the structure of the cell using the following picture and the words from exercises 1 and 2:
Ex. 11. Check your memory and try to recall the translation of the following verbs:
to perform, to store, to transmit, to house, to isolate, to surround, to damage, to enclose, to contain, to regulate, to carry out.
Make up word combinations with them of your own.