Chapter 2: Cells Flashcards
Cell to cell communication by direct contact.
Juxtacrine
Cell to cell communication by soluble mediators acting near groups of cells.
Paracrine
Cell to cell communication by direct contact through soluble mediators acting across a distance between cells.
Endocrine
Organelle that contains genetic information; directs metabolic function of cells
Nucleus
Surrounds cell nucleus; its structures carry out the directions of the nucleus
Cytoplasm
The basic structural and functional unit of the body (and life)
Cell
Group of similar cells performing the same function.
Tissue
Group of tissues
Organ
Groups of organs functioning together
Organ system
Integrated organ systems
Functioning Organism
What are cell membranes composed of?
Lipid and protein molecules
Double-layered membrane with pores that separates nucleus from cytoplasm
Nuclear membrane
Where is RNA located?
In nucleoli
Where is DNA located?
In chromosomes in the nucleus
Organelle that Contain enzymes that convert food materials (glucose, fatty acids, amino acids) into energy by oxidizing them, thereby producing water, carbon dioxide, and heat (for body temperature regulation).
Mitochondria
The essential fuel that powers chemical reactions in the cell.
ATP
Interconnected network of tubular channels enclosed by membranes that has nucleoprotein ribosomes attached to its surface that synthesize proteins for secretion by the cell or targeting to the cytoplasm
Rough Endoplasmic Reticulum (RER)
Organelle that has membranes containing enzymes that synthesize lipids (steroids) and break downdrugs and other molecules
Smooth endoplasmic reticulum (SER)
Flattened membrane-like sacs near the nucleus; connected with tubules of the RER; this is where large carbohydrate molecules are synthesized and combined with proteins.
Golgi Apparatus
This organelle digests worn-out cell components, organelles,and materials brought into the cell by phagocytosis; also prevents leakage of digestive enzymes into the cytoplasm that would injure cell; recycles intracellular structures as needed (“autophagy”)
Lysosomes
Process by which cellular organelles are degraded or recycled by the cell.
Autophagy
Ingestion of particulate foreign material by the cell.
Phagocytosis
A cytoplasmic organelle containing various enzymes, including those that decompose potentially toxic compounds through the production of H2O2.
Peroxisomes
These organelles break down free radicals, drugs, and alcohol in the cell.
Peroxisomes
Short, cylindrical structures located adjacent to the nucleus that participate in the formation of spindle fibers during cell division.
Centrioles
What is the function of the cytoskeleton?
1) Forms structural framework of the cell.
2) Determines cells shape
3) Responsible for cell movements
What are the three types of cytoskeleton proteins in cells?
1) Large microtubules
2) Intermediate filaments (4 types)
3) Microfilaments (actin)
In which cells are microfilaments (actin filaments) most plentiful?
Contractile cells (muscle)
Which type of intermediate filament is found in epithelial cells?
Keratin filaments
Which type of intermediate filament is found in nerve cells?
Neurofilaments
Which type of intermediate filament is found in connective and muscle cell?
Vimentin filaments
Which type of intermediate filament is found in involved in nuclear structure and found in all cells?
Lamin filaments
What percentage of human proteins have carbohydrate molecules attached?
70%
