Animal Anatomy and Physiology: Embryology

gamete

gamete

sex cell

oocyte

female sex cell

spermatozoan

male sex cell

zygote

fertilization of egg and sperm

zona pellucida

a thick layer rich in glycoproteins that surrounds the egg

mitosis

asexual reproduction

meiosis

sexual reproduction

morula

solid ball of cells

blastocyte (blastula)

hollow ball of cells with blastocele

blastocele

fluid filled cavity in blastocyst

inner cell mass

a solid clump of cells in the blastocyst, which later develops into the embryo

trophoblast

outer cells of the blastocyst the become the placenta

gastrulation

formation of 3 germ layers from the inner cell mass

epiblast

the outermost layer of an embryo before it differentiates into ectoderm and mesoderm

hypoblast

portion of inner cell mass next to blastocele the becomes the endoderm

what are the three germ layers

ectoderm, mesoderm, endoderm

ectoderm

the outer germ layer that develops into skin and nervous tissue

What does the ectoderm form from?

epiblast cells

mesoderm

middle germ layer that develops into muscles, and much of the circulatory, reproductive, and excretory systems

endoderm

the inner germ layer that develops into the lining of the digestive and respiratory systems

what does the endoderm form from?

hypoblast cells

what are the two layers of the mesoderm?

somatic and splanchnic

somatic layer

Adjacent to ectoderm and Gives rise to the bones, ligaments, blood vessels, and connective tissue of the limbs

splanchnic layer

Adjacent to the endoderm and forms the heart, gut muscles and blood vessels

coelom

fluid-filled body cavity lined with mesoderm

notochord

A rod of tough, flexible material that runs the length of a vertebrate's body, providing the majority of its support

neurulation

The first step in the development of the nervous system

germ layers form. . .

tissues

tissues form . . .

organs

organs form. . .

organ systems

when organs are in place, what is formed?

fetus

What are the four types of tissues?

epithelial, connective, muscle, nervous

what is the function of epithelial tissues?

protection, secretion, absorption

what are simple epithelial cells?

single layer of cells

what are stratified epithelial cells?

two or more layers of cells

How are epithelial cells classified?

according to the shape of the cells that appear on top and number of cell layers

squamous

thin and plate-like

simple squamous epithelium

single layer of flattened cells

endothelium epithelium

the specialized epithelial tissue that lines the blood and lymph vessels, body cavities, glands, and organs

mesothelium epithelium

The simple squamous epithelium that lines the ventral body cavities

mesenchymal epithelium

a squamous epithelium lining the subarachnoid spaces of the brain and chambers of the eyes

cuboidal

cube-shaped cells, as tall as they are wide

simple cuboidal epithelium

single layer of cube shaped cells

what is the function of simple cuboidal epithelium?

secretion and absorption

where is simple cuboidal epithelium located?

Kidney tubules, ducts and secretory portions of small glands, ovary surface.

columnar epithelium

cells taller than they are wide

where is columnar epithelium located?

lining of digestive tracks

what is the function of columnar epithelium?

secretion and absorption

transitional epithelium

a stratified epithelium in which the shape of the surface cells changes (undergoes transitions) depending on the degree of stretch

pseudostratified epithelium

Tissue with cells that appear to be in layers, but actually has only one

Where is pseudostratified columnar epithelium located?

lining of respiratory tract

stratified squamous epithelium

protects underlying tissues in areas subjected to abrasion such as the mouth and esophagus

keratinizing

cells that fuse together to minimize fluid loss and increase protection

what are the two types of glands in the body?

exocrine and endocrine glands

exocrine glands

secrete chemical substances into ducts that lead either to other organs or out of the body

endocrine glands

glands that secrete chemicals called hormones directly into the bloodstream; ductless

what are the three types of physical glands?

holocrine, apocrine, and merocrine

holocrine glands

accumulate their products within them until they rupture

apocrine glands

secretions gather at the outer ends of glands and then pinch off

merocrine glands

Exocrine glands that secrete without losing cellular material

what are the two types of epithelial membranes?

mucous and serous

mucous membrane

Membrane that secretes mucus and lubricates the surface of organs to keep them moist.

Where are mucous membranes located?

digestive, respiratory, urinary, and reproductive tracts

serous membrane

Membrane that lines a cavity without an opening to the outside of the body

Pericardium

The lining surrounding the heart

peritoneum

lines the abdominal and pelvic cavity

connective tissue

A body tissue that provides support for the body and connects all of its parts

what are the two types of connective tissue?

loose and dense

loose connective tissue

Tissue that binds epithelia to underlying tissues and holds organs in place. Contains collagenous, elastic, and recticular fibers.

what is loose connective tissue made up of?

fibroblasts

Fibroblasts

Cells that produce fibers in connective tissues

collagenous fibers

provide strength and are inelastic

elastic fibers

Flexible and "stretchy" fibers that add elasticity to tissue

reticular fibers

fine and highly branched, inelastic

amorphous ground substance

substance without form

fibrocytes

maintain connective tissue fibers and matrix

what are the two types of dense connective tissue?

dense regular and dense irregular

dense regular connective tissue

arranged in parallel bundles and form tendons

dense irregular connective tissue

fibers that are interwoven and compacted to form dense matting, found on dermis of skin

muscle tissue

A body tissue that contracts or shortens, making body parts move.

What are the three types of muscle tissue?

skeletal, smooth, cardiac

skeletal muscle tissue

Voluntary muscle pulls on bones and causes body movements.

smooth muscle tissue

Involuntary muscle is found in the intestines, arteries, and veins.

cardiac muscle tissue

striated, involuntary, located only at the heart

nervous tissue

Tissue that senses stimuli and transmits signals throughout the body.

what are the two types of body cavities?

dorsal and ventral

what are the two cavities that make up the dorsal cavity?

cranial and vertebral

cranial cavity

houses the brain

vertebral cavity

contains the spinal cord

what are the two cavities that make up the ventral cavity?

thoracic and abdominopelvic

thoracic cavity

cavity housing lungs and heart

pleura

double-layered membrane surrounding each lung

visceral pleura

the inner layer of pleura that surrounds each lung

parietal pleura

outer layer of pleura lying closer to the ribs and chest wall

mediastinal space

Space separating the lungs.

abdominopelvic cavity

contains both the abdominal and pelvic cavities

pelvic cavity

Contains urinary bladder, reproductive organs, and rectum

peritoneum

membrane that lines the abdominal cavity

what are the folds of the peritoneum called?

omentum, mesentery, and ligaments

omentum

a fold of peritoneum connecting the stomach with other abdominal organs.