histology

The study of body tissues

What are the 4 major human body tissues?

What does this describe?

Cover all body surfaces

Line all body cavities and hollow organs (heart)

Are the major tissues of glands

What does this describe?

Bind structures together

Form a framework for organs and the body as a whole (bones)

Store fat, transports substances, protects against disease, help repair tissue damage

Composed of cells that have the ability to shorten or contract

Transmits impulses (messages) throughout the body

The study of the development of the fertilized egg and its differentiation into tissues and organs

The first cell of a new individual

Union of special reproductive cells called sperm and egg

Make gamete (reproductive cell); contains the haploid number of chromosomes… 23

Female gamete; contains the haploid number of chromosomes… 23

What is the diploid number of chromosomes the zygote contains after fertilization?

The duplication and division of the cell nucleus; cell passes on cell info.

What are the 4 phases of mitosis?

The cell division of the cytoplasm

What phase does this describe?

Time between cell division

Cell is not resting

Cell grows

Performs its physiological activities

DNA replication begins near end

What phase does this describe?

Nuclear membrane disappears

Cytoskeleton elements begin to disassemble

Chromosomes become visible

Centrioles move to opposite poles

Asters form centrioles + astral rays (microtubules)

Astral rays extend to form spindle fibers

Duplicated chromosomes shorten and thicken; each half = chromatid

What phase does this describe?

Chromosomes migrate to equator of the cell

Accomplished by spindle fiber lengthening/shortening

Ends when centrosomes divide

Kinetochore will attach to spindle fibers

What phase does this describe?

Individual chromosomes (formerly chromatids) separate from each other and move apart toward opposite poles

Ends when chromosomes reach the poles

Chromosomes move away from the equatorial plate toward the poles

Accomplished by spindle fibers shortening

Polar microtubules push against each other; thus, pushing centrioles apart

What phase does this describe?

Chromosomes have reached the poles and begun to decondense

New nuclear membrane begins to form around each set of chromosomes

Kinetochore microtubules dissolve

Polar microtubules continue to elongate

What does this describe?

Division of the cell’s cytoplasm

Process where the cell divides into 2

Cleavage furrow is first sign

Actin filaments form a contractile ring

Ring contracts until cell pinches off forming 2 daughter cells

Sight of plasma membrane invagination

Usually appears near end of anaphase

The study of the development of the fertilized egg and its differentiation into tissues and organs

An individual in its earliest stages of development

Humans: from implantation to 8th week of pregnancy

From 8th week to birth

The development of the embryo

What are the 4 stages of development?

First cell in new individual

Result of conception/fertilization

Contains the genetic information (DNA) to become a child

1 cell

Solid ball of cells (16-64 cells; no bigger than zygote)

Result of repeated cell division of the zygote

Hollow ball of cells

Results when cells center of morula bind tightly together to form a compact sphere

Outer layers of cells that will eventually become the placenta

Apart of blastula

Inner cell mass

70-100 cells

Eventually becomes the embryo

Apart of blastula

Developmental stage in which embryoblast is reorganized into three layers of germ cells

Ectoderm, mesoderm , endoderm

Outside layer; surrounds the other layers

Middle layer

Inside layer; lies at the most interior of the embryo

the process whereby an undifferentiated embryonic cell acquires the features of a specialized cell such as heart, liver or muscle cell; transformation of cells into tissues

What 4 major body tissues do the primary germs layers, ectoderm, mesoderm, and endoderm, give rise to?

human embryonic stem cells are undifferentiated cells that can develop into any of the specialized cell types found in the human body

can develop into all cell types (zygote/morula); type of stem cell

can develop into all cell types except embryonic membranes- give rise to the 3 primary germ layers; type of stem cell

can develop into a limited number of cell types (hematopoietic (any type of blood) stem cells)

What primary germ cell is apart of…

epidermis of skin and its derivates

cornea and lens of eye

adrenal medulla

tooth enamel

epithelium of pineal and pituitary glands

nervous system

sensory receptors in epidermis

What primary germ cell is apart of…

notochord

skeletal system

muscular system

muscular of stomach and intestines

excretory system

circulatory and lymphatic system ( except germ cells)

dermis of skin

lining of body cavity

adrenal cortex

What primary germ cell is apart of…

epithelial lining of digestive tract

epithelial lining of respiratory system

lining of urethra, urinary bladder, and reproductive system

liver

pancreas

thymus

thyroid and parathyroid glands

What do these functions describe?

protect exposed portions of the body’s organs and safeguard them from abrasion and injury

control the passage of materials from the outside environment to specialized body cells below

found at the surface of the body organs

have no blood vessels of their own

reproduce a high rate; two surfaces

composed of layers (strata) of cells

named accordingly to cell shape and arrangement

free surface

bound surface

single layer of cells

multiple cell layers

extremely thin and irregular shape

have appearance of fish scales

Cube shaped like dice

Shaped like columns

Longer than they are wide

Meshwork of fine protein filaments and protein fibers on which the tissues sits

Produce by the epithelial cells

Intercellular connections

3 types- tight, desmosomes, gap