Unit 1 - The Cell V2 Flashcards
Describe the Cell
The basic structural unit of all plants and animals. Cells are specialized to carry out all the body’s basic functions
What are the three main elements of the cell?
Cell membrane, cytoplasm, and organelles
Define cell membrane
The outer covering of a cell
Define semipermeable
Able to allow some, but not all, substances to pass through.
(Cell membranes are selectively semipermeable)
Define cytoplasm
Thick fluid that fills a cell
Define organelles
Structures that perform specific functions within a cell
Describe nucleus
The organelle within a cell that contains DNA, surrounded by a membrane
Define Adenosine Triphosphate (ATP)
A high energy compound present in all cells, especially muscle cells; when split by enzyme action, it yields energy. Energy is stored in ATP
Define tissue
A group of cells that perform a similar function
Define epithelial tissue
The protective tissue that lines internal and external body tissues
(i.e. skin, mucous membranes, the lining of the intestinal tract)
Define muscle tissue
Tissue that is capable of contraction when stimulated./
List the three types of muscle tissue
- Cardiac (Spontaneous or self excited)
- Smooth (Involuntary)
- Skeletal (Voluntary)
Define connective tissue
Most abundant body tissue. Provides support, connection, and insulation
(i.e. bone, cartilage, fat, blood)
Define nerve tissue
Tissue that transmits electrical impulses throughout the body
Define organ
A group of tissues functioning together
Define organ system
A group of organs working together
Define organism
The sum of all the cells, tissues, organs, and organ systems of a living being
Define homeostasis
The natural tendency of the body to maintain a steady and normal internal environment
Define anatomy
The structure of an organism; body structure
Define physiology
The functions of an organism; the physical and chemical processes of a living thing
Define metabolism
The total changes that take place during physiological processes
Define negative feedback loop
Body mechanisms that work to reverse, or compensate for, a pathophysiological process, (or to reverse any physiological process, whether pathological or nonpathological)
What are the two kingdoms of cells?
- Prokaryotes
- Eukaryotes
Where at types of cells are Prokaryotes?
Prokaryotes are the cells of lower plants and animals
(i.e. blue-green algae and bacteria)
True or false, Prokaryotes have a distinct nucleus, internal structure, and are incased by cell membranes?
False
Where at types of cells are Eukaryotes?
Eukaryotes are the cells of higher plants and animals
(i.e. most algae, fungi, protozoa, and humans)
Which is more complex? Prokaryotes or Eukaryotes?
Eukaryotes
List the vital functions of the cell membrane
- Electrolyte / fluid balance
- Transfer of enzymes, hormones, and nutrients into/out of the cell
Why do antibiotics target the cell membranes of bacteria?
Because destroying the cell membrane kills the cell
Define cytosol
Clear liquid portion of the cytoplasm in a cell
Define cytoskeleton
Structure of protein filaments that supports the internal structure of a cell
Define erythrocyte
Red Blood cell
Define leukocyte
White blood cell
Define thrombocyte
Blood cell responsible for clotting, also called a platelet
Define lymphocyte
A type of leukocyte that attacks foreign substances as part of the body’s immune response
Define phagocyte
A cell that has the ability to ingest other cells such substances as bacteria and cell debris
Define phagocytosis
Ingestion and digestion of bacteria and other substances by phagocytes
Define monocyte
White blood cell with a single nucleus; the largest normal blood cell
Define granulocyte
White blood cell with multiple nuclei that has the appearance of a bag of granules
Define cytokine
Protein produced by a white blood cell that instructs neighboring cells to respond in a genetically reprogrammed fashion
Define cytotoxin
Substance that is poisonous to cells
Define cytotoxic
Poisonous (toxic) to cells
What substances dissolve in cytosol?
- electrolytes
- proteins
- glucose
- lipids (fatty substances)
Define organelles
Structures that perform specific functions within a cell
List the most important organelles within a cell
- nucleus
- endoplasmic reticulum
- golgi apparatus
- mitochondria
- lysosomes
- peroxisomes
Describe endoplasmic reticulum
A network of small channels that has both rough and smooth portions
List the functions of endoplasmic reticulum
Rough endoplasmic reticulum functions in the synthesis (building) of proteins. Smooth endoplasmic reticulum functions in the synthesis of lipids.
Describe golgi apparatus
Located neat the nucleus of most cells. Functions include synthesis & packaging of secretions like mucus and enzymes
Describe mitochondria
The mitochondria converts essential nutrients into energy sources, often in the form of Adenosine Triphosphate (ATP)
Describe lysosomes
Lysosomes contain digestive enzymes. Their functions include protein against disease and production of nutrients, breaking down bacteria and organic debris that has been taken into cells and releasing usable substances, such as sugars.
Describe peroxisomes
Similar to lysosomes. Especially abundant in the liver, they absorb and neutralize toxins.
What does “differentiation” do to cells?
Makes cells more specialized to accomplish specific tasks.
What are the seven major functions of cells?
- movement
- conductivity
- metabolic absorption
- secretion
- excretion
- respiration
- reproduction
