Chapter 1.1 - Cells Flashcards
What is the cell theory?
The cell theory states that:
* all organisms consist of cells or the products of cells.
* all cells come from pre-existing cells by the process of cell division.
* cells are the building blocks of life.
What defines a living thing?
A living thing is defined by its ability to carry out fundamental processes associated with life called life processes.
What are the main life processes?
- Maintaining a stable internal environment
- Controlled exchange of materials
- Response to stimuli
- Obtaining energy and chemical elements
- Transport of materials
- Removal of waste
- Cell division
- Growth and development
- Independent movement
- Reproduction
What is an organism?
An organism is a living thing that can be unicellular or multicellular.
What is the smallest independent unit of life?
The cell.
What is the composition of the cytoplasm?
The cytoplasm consists of a volume of fluid mostly made up of water in which substances are dissolved and some insoluble proteins.
What are unicellular organisms?
Unicellular organisms are living things that consist of one cell only, such as bacteria, fungi, protists, and algae.
What are multicellular organisms?
Multicellular organisms are living things that consist of large numbers of cells, such as mushrooms, animals, and plants.
What is DNA?
DNA (deoxyribonucleic acid) is a chemical found in special structures called chromosomes, responsible for making important molecules and passing on genetic material.
What is heredity?
Heredity is the passing on of characteristics genetically from one generation to the next.
What is the structure of a cell membrane?
The cell membrane is a thin layer consisting of two layers of phospholipid molecules with embedded proteins.
What is the Fluid-mosaic model?
The Fluid-mosaic model describes the structure and function of the cell membrane, where ‘fluid’ refers to the mobility of lipids and proteins, and ‘mosaic’ refers to the pattern of proteins in the membrane.
What is a light microscope?
A light microscope is an instrument used to produce a magnified image of a specimen, capable of magnifying up to about 1500x.
What is an electron microscope?
An electron microscope uses a beam of electrons to provide high-resolution images of cell structures, allowing for magnification tens or hundreds of thousands of times.
Fill in the blank: The process by which cells divide to produce new cells is called _______.
cell division.
True or False: All cells are the same size and shape.
False.
What is the estimated number of cells in an adult human being?
About 35 trillion cells.
What are the main components found in the nucleus of cells in multicellular organisms?
DNA and histones.
What is the primary function of the nucleus in a cell?
To control the overall function of the cell.
