CELLS LIVING UNITS Flashcards
The cell (from Latin _____, meaning “________”) is the basic structural, functional, and biological unit of all known living organisms.
cella, small room
A ____ is the smallest unit of life.
Cell
______ are often called the “building blocks of life”.
Cells
► The English Scientist ________ first observed plant cells with a crude microscope in the late 1600s.
Robert Hooke
►In the 1830s, 2 German scientists, ______ and _______, proposed that all living things are composed of cells.
Matthias Schleiden and Theodor Schwann
► German Pathologist _________ extended this idea by contending that cells arise only from other cells.
Rudolf Virchow
Since the late 1800s, cell research has been exceptionally fruitful and provided us with four concepts collectively known as the ________.
CELL THEORY
A ____ is the basic structural and functional unit of living organisms. When you define its properties, you define the properties of life.
cell
According to the principle of ________, and ______, the biochemical activities of cells are dictated by their shapes or forms, and by the relative number of subcellular structures they contain.
complementarity of structure and function
►Cells can only arise from other _____.
Cells
Cells that store nutrients?
Fat cell
Cell that Fight disease?
Macrophage
______- Cells that gather information and controls body functions?
______ - has long processes for receiving
Nerve cell, Neuron
What is the 3 main parts of Human cell?
- Plasma Membrane
- Cytoplasm
- Nucleus
The ________: is the outer boundary of the cell which acts as a selectively permeable barrier.
Plasma Membrane
The ________: The intercellular fluid packed with organelles, small structures that perform specific cell functions.
Cytoplasm
The ________:is an organelle that controls cellular activities. Typically, it lies near the cell’s center.
Nucleus
________, also called extracellular fluids, include interstitial fluid, blood plasma, and cerebrospinal fluid.
Body Fluids
Substances contributing to body mass that are found outside the cells.
Extracurricular Materials/Extracurricular Fluids
It’s like a rich, nutritious “soup,” interstitial fluid contains thousands of ingredients, including amino acids, sugars, fatty acids, regulatory substances, and wastes.
Extracurricular Materials/Extracurricular Fluids
To remain healthy, each cell must extract from this mix the exact amounts of the substances it needs depending on present conditions.
Extracurricular Materials/Extracurricular Fluids
_________ include substances that aid in digestion (intestinal and gastric fluids) and some that act as lubricants (saliva, mucus, and serous fluids.)
Cellular secretions
The _________ is the most abundant extracellular material. Most body cells are in contact with a jellylike substance composed of proteins and polysaccharides.
extracellular matrix
Secreted by the cells, these molecules self- assemble into an organized mesh in the extracellular space, where they serve as a universal “_______” that helps to hold body cells together
cell glue
• The flexible _______ Separates two of the body’s major fluid compartments
- Intracellular fluids (ICF)
• 2. Extracellular fluids (ECF)
PLASMA MEMBRANE
The term _________ is commonly used as a synonym for plasma membrane
cell membrane
■ Give the Functions of PLASMA MEMBRANE:
- MECHANICAL BARRIER
- SELECTIVE PERMEABILITY
- ELECTROCHEMICAL
- COMMUNICATION
- CELL SIGNALING
PLASMA MEMBRANE
_______ - It Separates two of the body’s fluid compartments.
MECHANICAL BARRIER
PLASMA MEMBRANE
________ - Determines manner in w/c substances enter or exit the cell.
SELECTIVE PERMEABILITY
PLASMA MEMBRANE
_______ - Generates and helps to maintain the electrochemical gradient required for muscle and neuron function.
ELECTROCHEMICAL GRADIENT
PLASMA MEMBRANE
________: Allows cell-to-cell recognition (E.g., of egg by sperm) and interaction.
COMMUNICATION
PLASMA MEMBRANE
_______: Plasma membrane proteins interact with specific chemical messengers and relay messages to the cell interior.
CELL SIGNALING
PLASMA MEMBRANE
• The _______ forms the basic “______” of the membrane. It is constructed largely of phospholipids, with smaller amounts of glycolipids and cholesterol.
lipid bilayer, fabric
Membrane Lipids
PHOSPHOLIPIDS: Each lollipop-shaped phospholipid molecule has a polar “head” that is charged and is _______ (WATER LOVING).
hydrophillic
Membrane Lipids
The non polar “tails”, being ________ (WATER FEARING), avoid water and line up in the center of the membrane.
hydrophobic
Membrane Lipids
________: They consist of two parallel sheets of phospholipid molecules lying tail to tail, with their polar heads bathed in water on either side of the membrane or organelle.
Sandwich-like structure
Phospholipid Bilayer,
“Bi” means?
Two →_→
______ molecules have unequal sharing of electrons among atoms.
Polar
Membrane Lipids
________ - Are lipids with attached sugar groups. Found only on the outer plasma membrane surface, it accounts for about 5% of the total membrane lipids.
- GLYCOLIPIDS
Membrane Lipids
Some 20% of membrane lipid is ________.
Cholesterol
________ - It stabilizes the membrane, while decreasing the mobility of the phospholipids and the fluidity of the membrane.
Cholesterol
What is the 2 types of Membrane Proteins?
- Integral Protein
- Peripheral Protein
Membrane Proteins
________ - have both hydrophobic and hydrophilic regions.
INTEGRAL PROTEINS