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Flashcards in tissues Deck (101)
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1

group of cells that usually have a common origin in an embryo
-function together carry out specialized activities

Tissue –

2

composed mostly of cells with little extracellular material tightly packed together
-arranged in sheets and attached to a basement membrane
-avascular (not supplied by blood capillaries) and is nourished by diffusion from the capillaries of underlying connective tissues

Epithelial tissues –

3

– lines blood vessels and air sacs of lungs; cardiovascular and lymphatic system
-permits exchange of nutrients, wastes, and gases (O2 and CO2)
-flat, thin and scale-like; allows for rapid passage of substances through them
-function: diffusion

Simple squamous

4

– lines kidney tubules and glands
-function: secretes and reabsorbs water and small molecules
-cubelike; may have microvilli at the apical (free) surface
-role of microvilli: increase surface area for absorption

Simple cuboidal

5

- lines most digestive organs and the gallbladder
-absorbs nutrients and produces mucus
-contains columnar epithelial cells with microvilli and goblet cells

Simple columnar

6

– appears to have multiple layers of cells because the cell nuclei lie at different levels and not all cells reach the apical surface, but it is actually a simple epithelium because all its cells rest on its basement membrane
-pseudo because of varying positions of cells
-clue: all components are attached to a common basement membrane

Pseudostratified epithelium

7

outer layer of skin (epidermis), mouth, vagina
-protects against absorption, drying out (desiccation), infection

stratified squamous

8

lines ducts of sweat glands and male urethra
-secretes water and ions
-2 or more layers

Stratified cuboidal

9

lines epididymis, mammary glands, larynx
-secretes mucus
-part of the conjunctiva (thinnest skin) of the eye

Stratified columnar

10

– appearance is variable
-cells change shape from squamous to cuboidal and back (like the urinary bladder)
-depends on the organ
-role of cilia: aid secretion and absorption of whatever substance

• Transitional Epithelium

11

space/central part of cuboidal cells

Lumen –

12

– unicellular gland, epithelial cell; its secretion is mucus (sole function) to protect the organ from cell digestion
-look like empty sac-like structures

Goblet cell

13

forms brush border

microvilli

14

– lines the tracheal airway
-not a true stratified tissue
-mucus produced by goblet cell traps dust and other debris, and the cilia propel the mucus upward and away from the lungs
-Location: lining of nasal cavity, nasal sinuses, pharynx, auditory tubes, bronchi of the lungs
-“respiratory epithelium”
-function: secretes mucus and moves mucus and debris

Pseudostratified Ciliated Columnar Epithelium

15

-highly specialized to contract or shorten, to produce movement
-muscle cells are elongated to provide a long axis for contraction hence, they are called muscle fibers

MUSCLE TISSUE

16


1. Excitability – ability to respond to stimuli
2. Contractility - ability to shorten forcefully
3. Extensibility – ability to stretch
4. Elasticity - ability to resume resting length after contraction
5. Tonicity - ability to maintain steady state of partial contraction

properties of muscle tissue

17

contractile elements
-basic structural and functional unit of skeletal muscle
-segment between Z disks

sarcomere

18


-receives stimuli from environment or from different organs
-transmits impulses to brain and spinal cord
-bring appropriate motor responses

nervous tissue

19

properties of nervous tissue

irritability and conductivity

20

elements of nervous tissue

neurons
neuroglia

21

parts of neuron

cell body soma cyton perikaryon
processes

22

type of neuron
many processes
-many dendrites one axon
-starlike; fish eye
-seen in the brain and spinal cord

multipolar

23

type of neuron
two processes
-1 axon, 1 dendrite
-sensory neurons of eyes, nose, ears
-spindle shaped appearance of nerve cell

bipolar

24

type of neuron
– 1 process
-only one axon
-will branch and act as dendrite, the other as axon
-owl’s eye

unipolar

25


-mainly composed of extracellular matrix of ground substance and protein fibers
-highly vascular except for cartilage, tendons, and ligaments
-consist of 2 basic elements: extracellular matrix (protein fibers and ground substance) and cells
-cells are derived primarily from mesenchymal cells

Connective Tissues

26

-large, flat cells with branching processes
-secrete extracellular matrix
-true connective tissue cells

fibroblasts

27

– large, irregular –shaped with short blunt cytoplasmic processes
-develop from monocytes (a WBC type)
-capable of engulfing bacteria and cellular debris
-capable of phagocytosis; have pseudopods for engulfing

Macrophages

28

– many granules
-abundant basophilic cytoplasmic granules which obscure the nucleus
-produce histamine, chemical that dilates small blood vessels as part of inflammatory response
-can bind, ingest, kill bacteria

Mast cells

29

have signet ring appearance; nucleus is on the side (like the ‘pendant’ of a ring)
-specialized for fat storage

adipocytes

30

cart-wheel or wall clock appearance
-develop from a type of WBC called B lymphocytes
-have characteristic clock face or cart wheel appearance around the nuclear envelope
-principle produces of antibodies

Plasma cells –

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