1.8 Say whether these statements are true or false
1 Cell membrane, cytoplasm and the nucleus are the main parts of Prokaryotic cells.
2 Plasma membrane has two main functions: protection of the cytoplasm and its organelles and exchange of material into or out of the cell.
3 Between the cell membrane and the nucleus there is the cytoplasm.
4 Cell organelles have special functions in the cell.
5 The nucleus is the brain of the organ.
6 Genetic materials are foundin the nucleus.
7 Plant cells have a firm structure because of the cell wall.
8 The cell can move with the help of flagellum and cilia.
9 Diffusion is the movement of molecules from areas of low concentration to areas of high concentration.
10 Osmosis is the diffusion of oxygen.
11Active transport is the movement of molecules from the areas of low concentration to the areas of high concentration. In this process cells don’t use energy.
12 Active transport occurs only in living cells.
1.9 Answer the following questions
1 What are the main parts of Eukaryotic cells?
2 What is plasma membrane made of?
3 What are the functions of the cell membrane?
4 Where is the cytoplasm located?
5 What are the functions of cell organelles?
6 What are the functions of a nucleus?
7 What is the cell wall?
8 How is materials exchange provided?
9 What is diffusion?
10 What is osmosis?
11 What is active transport?
1.10 Summarize the text in no more than 15 sentences
II. Watching the video
a. Watch the video and answer the questions
Unit VI Bioenergetics
Read the text, pay attention to the highlighted words
All living things require energy because life processes involve work. Energy is the capacity to do work. Cells need energy to grow and reproduce, but even non-growing cells need energy to survive.
Sun is the source of energy almost all organisms depend on. In photosynthesis, plants and other photosynthetic organisms capturesolar energy and convert it to chemical energy.
Metabolism
Metabolism is the sum of the biochemical reactions in the cell. All life activities in the cell are also called metabolism.Metabolism can be divided into two types: anabolism and catabolism. Anabolism is the biosynthesis reactions. In anabolic reactions, such as photosynthesis, big molecules are made from simple ones.
Catabolism is the breaking down reactions. In catabolism, such as cellular respiration, big molecules are broken down into simple ones.
ATP
All organisms can use ATP as energy source. Food molecules contain chemical energy. In cellular respiration, this energy is released as ATP. Organisms use ATP for energy.
How cells make ATP: The organism extracts energy from food in stages. First food is digested. That means proteins, carbohydrates and fats are broken down into simple molecules. Then these simpler molecules undergo cellular respiration or catabolism. In cellular respiration, energy in food molecules is released as ATP.
Enzymes
Biochemical reactions require enzymes. Enzymes are biochemical catalysts. They speed up reactions. Without enzymes life processes would occur very slowly. Enzymes have many special properties.
Photosynthesis or capturing sunlight energy
Photosynthesis lies at the heart of biology. The sun is the unique source of energy that almost all organisms depend on. The amount of radiant energy that reaches the earth from the sun each year is the equivalent of about 100 million Hiroshima-sized atomic bombs. About a third of this energy is reflected back into space, and most of the remainder is absorbed by the earth and converted into heat. Less than 2% of the energy that reaches the earth is captured by photosynthesis. But that is enough to provide the energy that drives almost all of the activities of life on earth.
In photosynthesis, plants and other photosynthetic organisms capture solar energy and convert it to chemical energy. The chemical energy is stored in seeds or other parts of the plant's body. When an animal eats plants, this energy passes from the plants' to the animal's body. Plants also produce oxygen by photosynthesis, which takes place in chloroplasts. The overall reaction of photosynthesis is:
Water + Carbon dioxide + Light energy = Sugar + Oxygen
Cellular respiration or harvesting ATP energy
Life is driven by energy. All of the activities that organisms carry out use energy. You know that plants and other photosynthetic organisms harvest theenergy of sunlight by the process of photosynthesis. Energy is required to powerlife processes. Most autotrophs depend on energy from the sun to fuel the synthesis of food, while heterotrophs depend on the energy stored in autotrophs fortheir energy.
The bodies of organisms contain many enzymes that are employed in harvesting energy from food. Most foods contain a variety of carbohydrates, proteins, andfats, all rich in energy. The work of extracting energy from these food molecules iscalled cellular respiration.
Organisms extract energy from food in stages. First food is digested. Thatmeans that proteins, carbohydrates and fats are broken down into simple molecules.Then these simpler molecules undergo cellular respiration, or catabolism, in whichcells generate ATP from food molecules. This takes place in mitochondria. Theoverall reaction of cellular respiration is:
Sugar + Oxygen = Water + Carbon dioxide + ATP energy