Chapter 18 Cells And tissues Flashcards
Anatomy
Study of the structures of the human body and their positional relationships to one another the study of anatomy can be approached in several ways
Physiology
Study of how the body and its individual parts function is normal body processes
Homeostasis
Tendency of the body’s internal environment remain relatively constant with a narrow range of change
Levels of organization
- Chemical level
- Cellular level
- Tissue level
- Organ level
- Organ system level
- Organism level
Cell
The cell is the smallest structural functional unit that can exist as a self-sustaining entity
75 200 trillion cells are present in the body at any given moment
Cell elements are
Carbon, oxygen, hydrogen, nitrogen and trace elements
Trace elements are calcium, iron, iodine, sodium, potassium
Calcium
Calcium is needed for blood clotting
Iron
Necessary to make hemoglobin which transports oxygen in blood
Iodine
Iodine Needed for thyroid hormones which controls or adjust metabolism
Water percentage of a cell
Water makes up 60 to 80% of all cells
Cell membrane
Facilitates the exchange of nutrients and waste materials
Cytoplasm
Provides cellular nutrition and supports organelles
Organelles
Carries out the maintenance and functions of the cell
Endo plasmic reticulum
Synthesizes proteins and lipids; Metabolizes carbohydrates and steroids; regulates calcium concentration; protein transport
Roadways of the cell
Ribosomes
Protein factories
Synthesizes proteins
Golgi body
Synthesizes proteins and lipids and packages them for delivery outside the cell
Packing and shipping plants of the cell
Mitochondrion
Site of cellular respiration; provides most of the cells ATP
Power plants of the cell
Lysosome
Garbage disposals of the cells
Engulfs, destroys, and I just pathogens and cellular debris
Nucleus
Control center of the cell
Directs most metabolic activities, including growth and reproduction; contains DNA and RNA
“Gatekeeper “of the cell
Cell membrane
Cytoplasm also known as
Proto plasm
Endoplasm is inside the organelle
Cytosol is outside the organelle
Mitochondria
Inner membrane folded into chamber called Cristae
Cells “power plants “
Only place in the sour food molecules are combined with oxygen and digested
Provide most of the cells adenosine triphosphate (ATP)
Centrioles
Paired tubular structures that help cells divide
North and South Pole
Nucleus
Contains DNA and RNA
Humans possess 23 pairs of chromosomes
Nucleolus resides in nucleus
Cytoskeleton
Scaffolding material of a cell
Provides internal structure
Helps move substances across the cell membrane
Cellular extensions; microvilli, Cilia, flagella,
Cellular processes: Passive
Passive processes do not require energy or activity of the cell membrane
Diffusion, Osmosis, filtration
Molecules move because of differences in concentration pressure or temperature
Differences are called gradients
Diffusion
High to low
Simple- no carrier molecule
Facilitated - requires carrier molecule
Movement of molecules from an area of high concentration to an area of low concentration
Example lump of sugar dropped into glass
Osmosis
Low to high
Movement of water across the cell membrane from an area of low concentration to high concentration to equalize fluid concentration on both sides of the membrane
Selective permeable membrane
Only allows water diffusion
Filtration
Pressure
Movement of water and molecules across the cell membrane due to pressure
“blood pressure quote
Cellular processes: active
Transport From lower concentration to higher concentration
One. Transport by membrane pumps
Two. Transport by Vesicles
Membrane pump
Cellular process
Carrier molecules that are located within the cell membrane
Muscle cells use calcium pumps
Nerve cells use salt in potassium pumps
Pump mechanisms require ATP
Energy released during the breakdown of ATP is transferred to the pump
Transport by vesicle
Exocytosis
Involves moving substances outside the cell
Endocytosis
Moving substances inside the cell
- Phagocytosis and pinocytosis
Phagocytosis
Cell eating
A piece of the cell membrane is wrapped around large molecules and are drawn inside the cell
Vesicle fuses with a lysosome coats the large molecule with digestive enzymes and digests it
Killing a large molecule usually a pathogen
Digested products are released via exocytosis
Pinocytosis
Cell drinking
Targeted substance is liquid
Pinocytosis cells are more common than phagocytic cells
Tissues
Four principal types
Epithelial tissue
Connective tissue
Muscular tissue
Nervous tissue
Cellular
Sum total of all physicalAnd chemical processes that occur in an organism
Overall rate at which reactions use energy
Exercise elevated body temperature, or mono activity, digestion and pregnancy all increase rate you
Baseline rate or basal rate
Anabolism
- Constructive phase
- Small, simpler molecules are built up into large molecules
- Amino acids combining to form proteins
Catabolism
- Destructive phase of metabolism
- Larger, complex molecules are broken down into simpler molecules
- Carbohydrates are broken down into glucose
Embryonic tissue layers
- Ectoderm; outer most
- Mesoderm; middle
- Endoderm; innermost
Tissue – interstitial fluid
Found an extra cellular spaces between tissues
Primarily water and contain substances salts, sugars, fatty acids, amino acids, hormones, Nero transmitters,
Based sales and provide transport medium for nutrients, gases, and Waze
More abundant and then plasma or lymph
Epithelial tissue
Lines or covers external and internal body structures, lines open and closed body cavities
Closely packed cells in one or more layers. High rate of cell division, regenerates quickly
Bound to underlying tissues by “basement membrane “
Provides; protection, Absorption, secretion, excretion, and sensation
Endothelium – covers internal services of blood and lymph Fattic vessels
Glandular epithelium – found an endocrine and exocrine glands
Connective tissue
Four types; fibrous, bone, cartilage, blood
Most abundant tissue in the body
Connects, supports, transports, and defense
Forms framework for organs and glands and for body as a whole
Consist of protein fibers scattered in a matrix; elastin, collagen, and reticular
Fibrous connective tissue
4 types
- Loose – most widely distributed type, elastic glue, connects adjacent structures and permits movement
Helps organs and muscles slide with no friction - Adipose- fat; serves as storage, insulation, protection
- Reticular - supportive framework for bone, bone marrow, lymph nodes and organs
- Dense - compact, strong bundle of fibers
- regular: parallel rose, elastic, great tensile strength in two directions
- irregular: Interwoven fibers; strong, thick sheet of connective tissue, resist pulling in multiple directions; deep fascial sheath, dermal layer, periosteal sheath
Bone
Osseous tissue
Hardest type,
Skeletal system, support, protection, muscle attachment sites, store minerals and fat, produce blood cells,
Compact and spongy
Cartilage
3 types
Hyaline cartilage Dash most prevalent; articulating cartilage, costals , trachea
Fibrocartilage- strongest; Intervertebral disc’s, meniscus of the knee
Elastic cartilage - softest, pliable; ears, nose, lyrics
Cartilage is a strong connective tissue with stands repeated stress
Avascular - Minimal healing (low blood flow)
Blood
Liquid connective tissue
Red blood cells, white blood cells, platelets, plasma
Muscle tissue
Three types
- Skeletal
- Smooth muscle
- Cardiac muscle
Skeletal muscle
Voluntary
Attached to bones most abundant
Long, cylindrical threadlike
Nuclei are peripherally located
Contains bands, giving striated or striped appearance
