A microscope is an instrument that makes small objects look larger.
Why was the discovery (invention) of the microscope so important?
The invention of the microscope made it possible for people to discover and learn about cells.
What is a compound microscope?
A compound microscope is a light microscope that has more than one lens.
What is the cell theory?
The cell theory is a widely accepted explanation of the relationship between cells and living things.
What three things does the cell theory tell us?
The cell theory tells us that:
1. All living things are composed of cells.
2. Cells are the basic unit of structure and function in living things.
3. All cells are produced from other cells.
What is magnification?
Magnification is the ability to make things look larger than they are.
What is resolution?
Resolution is the ability to clearly distinguish the individual parts of an object.
What are organelles?
Organelles are small structures within cells that carry out specific functions within the cell.
What is the cell wall?
The cell wall is a rigid layer of nonliving material that surrounds the cells of plants and some other organisms.
The function of the cell wall is to support and protect the cell.
What is the nucleus?
The nucleus is the control center of a cell that directs the cells activities.
The function of the nucleus is that it contains the chemical instructions that direct all the cell's activities and determine the cell's characteristics.
What is cytoplasm?
Cytoplasm is the region of a cell located inside the cell membrane or between the cell membrane and nucleus: contains a gel-like material and cell organelles.
The function of Cytoplasm is to provide support to the internal structures of a cell.
What are mitochondria?
Mitochondria (rod shaped) are the powerhouses of the cell because they produce most of the energy the cell needs to carry out its functions.
The function of mitochondria is to provide energy for the cell.
What are endoplasmic reticulum?
Endoplasmic reticulum are a passageway through which proteins and other materials move within the cell.
The function of endoplasmic reticulum is to carry proteins and other materials from one part of the cell to another.
What are ribosomes?
Ribosomes are tiny structures in the cytoplasm of a cell where proteins are made.
The function of ribosomes are to act as factories that produce proteins.
What are chloroplasts?
Chloroplasts are a structure in the cells of plants and some other organisms that capture energy from sunlight and use it to produce food.
The function of chloroplasts is to capture energy from sunlight and use it to produce food for the cell.
What are vacuoles?
Vacuoles are water-filled sacs inside the cell that act as a storage area.
The function of vacuoles is to store food and other materials needed by the cell.
What are lysosomes?
Lysosomes are a small round cell structure that contains chemicals that break down large food particles into smaller ones.
The function of lysosomes are to break down food particles and also break down old cell parts and release substances to be used again (acts as the cell's clean-up crew).
What are golgi bodies?
Golgi bodies area a cell structure that receives proteins and other newly formed materials front he endoplasmic reticulum, packages them,and distributes them to other parts of the cell.
The function of golgi bodies is to distribute newly formed materials to other parts of the cell.
What is the nuclear membrane?
The nuclear membrane is a double-layered membrane that encloses the nucleus of the cell. It is also called the nuclear envelope.
The function of the nuclear membrane is to regulate the in/out movement of substances in a cell especially between the nucleus and the cytoplasm.
What is chromatin?
Chromatin is the material of which the chromosomes of organism other than bacteria area composed. It consists of protein, RNA, and DNA.
The function of chromatin is to transfer the DNA blueprints of a cell over to the RNA, protein, and other DNA copies. It makes sure that each of the blueprints is accurate.
What is the Nucleolus?
The nucleolus is a small, dense spherical structure in the nucleus of a cell during interphase.
The nucleolus' main function is producing and assembling subunits which form ribosomes.
How are bacterial cells different from other cells?
Bacterial cells do not have a nucleus!
Which cell organelles are found only in plant or animal cells and not the other?
Organelles are found only in plant cells.... are chloroplasts and cell walls.
Organelles found only in animal cells include... mitochondria and centrioles.
What substances were in the Earth's early atmosphere?
were in the Earth's early atmosphere.
How might life's chemicals come together to form early proteins and the building blocks of life?
when water and early atmospheric gases (nitrogen, water vapor, carbon dioxide, and methane) receive an electric current such as lightening... within a week's time, chemical units form and can create proteins when joined together.
How do scientists hypothesize that the first cells were formed?
Scientists hypothesize that small chemical units of life formed gradually over millions of years in Earth's waters.
Some of these units joined to form the large chemical building blocks that are formed in cells.
Eventually, some of these large chemicals accumulated and became the forerunners of the first cells.
What are six characteristics that all living things have in common?
Six characteristics that all living things have in common include...
contain similar chemicals
grow and develop
respond to their surroundings
What is a cell?
A cell is the basic unit of structure and function in an organism.
Unicellular (single-celled) organisms include bacteria, the most numerous organisms on earth.
Multicellular means composed of many cells.
What five important chemicals make up the cells of all living things?
2. carbohydrates (cell's energy source)
4. lipids (building materials of cells)
5. Nucleic (the genetic material)... the chemical instructions that direct the cell's activities.
How do living things use energy?
Living things use energy to move, grow, and to defend themselves.
What is the difference between growth and development?
Growth = is the process of becoming larger
Development = is the process of change that occurs during an organism's life to produce a more complex organism.
What is a stimulus?
A stimulus is a change in an organism's surroundings that causes the organism to react.
What is a response?
A response is an action or change in behavior.
What does it mean to reproduce?
To reproduce means to produce offspring that are similar to the parents.
What is spontaneous generation?
Spontaneous generation is the mistaken ideathat living things arise from non-living things.
When designing experiments, why should they always be controlled?
Experiments should always be controlled because in a controlled experiment....
a scientist carries out two tests that are identical in every way except for one factor. The one factor that the scientist changes is called the variable.The scientist can conclude that any differences in the results of the two test must be due to the variable.
What are the four basic needs of living things?
3. living space
4. stable internal conditions
Where do all living things get their energy from?
1. the sun
2. carbon dioxide
***These three things combine in the organism to make their own food.***
What is an autotroph?
An autotroph is an organism that makes its own food.
What is a heterotroph?
A heterotrophis an organism that cannot make its own food.
Why do all living things need water to survive?
Organisms need water to:
obtain chemicals from their surroundings
break down food
move substances within their bodies
Why do all living things need living things to survive?
All organisms need a place to live so that they can get food and water, and find shelter.
Why do some living things have to compete?
Some living things have to compete because there is a limited amount of living space on Earth.
What things do they compete for?
Living things compete for...
What is homeostasis?
Homeostasis is the maintenance of stable internal conditions despite changes in the surroundings.
Ex: Your body's regulation of temperature.
Look at the diagram to see parts of a cell...
An action or change in behavior is a _________?
An action or change in behavior is a response.
An organism that cannot produce its own food is called a _______________.
An organism that cannot produce its own food is called a heterotroph.
The sum of all chemical reactions in an organism is known as ______________.
The sum of all chemical reactions in an organism is known as metabolism.
The process by which the body breaks down food into small food into small food molecules is called _______________.
The process by which the body breaks down food into small food into small food molecules is called digestion.
The process of becoming larger is called _____________.
The process of becoming larger is called growth.
The maintenance of stable internal conditions despite changes in the surroundings is called _____________.
The maintenance of stable internal conditions despite changes in the surroundings is called homeostasis.
The production of offspring similar to parents is called ______________.
The production of offspring similar to parents is called reproduction.
The concept that all cells are produced from other cells is one of the main points of ___________________.
The concept that all cells are produced from other cells is one of the main points of the cell theory.
A statement that describes what scientists expect to happen every time under a particular set of conditions is called a ___________________.
A statement that describes what scientists expect to happen every time under a particular set of conditions is called a scientific law.
The general term for the tiny structures that carry out specific functions in a cell is _________________.
The general term for the tiny structures that carry out specific functions in a cell is organelles.
The structure that controls which substances can enter or leave the cell is called the ________________.
The structure that controls which substances can enter or leave the cell is called the cell membrane.
Which of the following acts as the cell's storage area?
The vacuoleacts as the cell's storage area.
The structure in the cell that produces proteins is called a _______________.
The structure in the cell that produces proteins is called a ribosome.
Photosysthesis takes place in the _________________.
Photosysthesis takes place in the chloroplast.
Which of the following structures is NOT found in a plant cell?
Lysosome is not found in a plant cell.
Bacterial cells differ from plant and animal cells because they do NOT have a ____________.
Bacterial cells differ from plant and animal cells because they do NOT have a nucleus.
True or False
Vacuoles contain chemicals that break down food and old cells.
True or False
The nucleus is the cell's control center.
The cytoplasm is the region between the nucleus and the cell membrane that contains air.
True or False
All cells have a cell membrane.
Review the labeled parts of a plant and animal cell.