analysis of organisms on a multicellular level (specialized cells)
tissues: groups of similar cells with similar embryonic development and function
organs: groups of similar tissues
organ systems
organism: an individual, in this case a multicellular one that possesses organ systems β organs β tissues
histology: tissue structure/function (derived from hist/o-, tissue or web)
types of animal tissues: epithelial, connective, muscle, nervous
epithelial
from epi-, outer; thelium (p. thelia), nipple/papilla/projection; -al, of or pertaining to or adjectival
tightly-packed, tightly-junctioned tissues which prevent materials from passing
basement membrane: secreted protein and glycoprotein membrane which anchors epithelial tissue to rest of organ
identify via number of cell layers and shape of cells
number of layers:
simple epithelial: singular layer
areas of passage (absorption/secretion β lungs and intestine)
stratified epithelial: multiple layers
areas of frictional stress and cover (skin, mouth and throat lining)
pseudostratified epithelial: single layer that appears stratified due to illusion of depth, created by differences in height amongst epithelial cells
shape:
squamous: thin and flat; derives from squame, squama: covering that is scale, plate, or flake-like; fish or reptile-like
cuboidal: you knowβ¦ like a cubeβ¦ cuboidβ¦
columnar: you knowβ¦ like a columnβ¦
naming conventions based on number/shape
for a stratified tissue: tissue is named by free, unattached surface of epithelial tissue layer
epidermis: outer layer; epi- + -dermis
nephron: microscopic tubules found in the kidneys, surrounded by blood vessel; used for the processing of urine and the primary component of the kidney
lumen: free space within a cell
villi (sg. villus); finger-like projections (derived from a latin word which references a thick tuft of hair, like fleece)
may be pseudostratified
evolved structures that increase the surface area of cellular lining of intestinal lumen β increase productivity of transport proteins and absorption of nutrients through intestinal wall
microvilli: microscopic folds in the cellular plasma membrane with identical function
brush border: the free, unattached surface of the cells surrounding the lumen
goblet cells: vase or goblet-shaped cells that contain light-staining mucous
secretion of mucous for lubrication and protection
connective
diverse junction and support tissues, including blood cell
contains a matrix: dividers made from extracellular material (secreted within tissues in the fibroblast cell) that separate cells in a given tissue
proteinaceous fibers: collagenous or elastic or etc. fibers; made from a given protein and submerged in a ground substance that keeps them from separating
collagen vs. elastin proteins; some have both, some only one
string-like
ground substance: dense liquid or gelatinous combination of glycoproteins and polysaccharides
named by density and fiber or protein
macrophages: large, grain-textured phagocytic cells made from wbcs
adipocytes: adipose tissue cells; tight packing with transparent/colorless triglycerides
blood cell matrix: plasma; serum ground substance, albumin proteins β blood viscosity and others β blood clots
mammalian erythrocytes are anucleated; concave hemoglobin disks that lack nuclei
non-mammalian are nucleated
five types of leukocytes; all are colorless
muscle
skeletal, cardiac, smooth muscle (digestive, blood, tract, involuntary movement muscles)
all muscle tissues can contract, perform mechanical work
distinguished muscle tissues
skeletal: long, multinucleic, ribbed pattern (striation) caused by arrangement of protein fibers used in contraction; cylindric; nuclei are on edges of tissue
smooth: no striation β name; thin, spindle-shape/tapering, uninucleic cells;
may be confused with dense fibrous connective tissue; nuclei are ovaline in smooth muscles and compressed in dfct
nervous
brain; electrical signaling β responses to stimuli and communications; action potential generates responses
large physiology unit
neuron: basic cell of nervous system; β dendrons; cell body with parts attached that rip off when spliced for slidework
large, star-shape cell body composed of motor neurons: possesses a single nucleus and nucleolus
neurofibrils; small, dark in stains
axon v. dendrite: axon is long-distance, transmits to other tissue cells; dendrite is short, transmits between neurons; thin axons are easy to tear
glial cell (Schwann cells are linear) β grow around axons, increase speed of transmission,
20240124 | phylogenetics
outgroup: distantly related taxa ie wolves and lions
family, genus
pinnae: ear flaps vs merged earholes (βear pinningβ)
summary code: symbolic representation of variation in characters
ie 0: ancestral state for character (assigned to outgroup)
1+: evolutionary novelty
distance matrix: calculate number of differences between taxa and use to calculate sister groups and distance on trees in values of number of differences
used for larger phylogenies
convergent evolution: common evolution in distinct separate species / systems due to similar environmental pressures
tasmanian wolf vs timber wolf
cytochrome c: cellular respiration
20240204
hypothesis: proposal that might be true β experiments
null hypothesis: predicts no difference or change between observed and expected (ratio), no difference across populations; no actual change
there is no difference between the expected genotype ratio of 25AA:50Aa:25aa and the observed ratio.
straightforward, understand what is being tested. boring tm
statistics determine meaningfulness or chance of experiment results; likelihood of repetition for outcome
chi square: ratio format data; observed to expected
compare o v e genotype, allele, phenotypic frequencies