DAF 200: Histology Lecture Notes

Practice flashcards for animal histology covering cellular organelles, chemical composition, primary tissue classifications (epithelial, connective, muscular, nervous), and glandular functions.

How is a 'tissue' defined in histology?

A collection of similar cells performing a similar type of function and united by intercellular substance.

What are the four primary tissue types?

Epithelial tissue, Connective tissue, Muscle tissue, and Nerve tissue.

What is the difference between hyperplasia and hypertrophy?

Hyperplasia refers to growth via an increase in cell number, while hypertrophy refers to growth via an increase in cell size.

What are the four main metabolic and functional processes occurring in mitochondria?

1. Citric acid cycle (Kreb’s cycle) 2. Oxidative phosphorylation ($ADP \rightarrow ATP$) 3. FA oxidation 4. Cytochrome oxidase enzymes.

How is the animal body's fluid composition divided by body weight (BW)?

Intracellular fluid (ICF) makes up $40\%$ of BW, and Extracellular fluid (ECF) makes up $20\%$ of BW ($15\%$ interstitial fluid + $5\%$ plasma).

Provide examples of simple proteins categorized as Albuminoids.

Collagen and elastin, which are found in connective tissue.

Name the five types of conjugated proteins and their respective prosthetic groups.

1. Glycoproteins (CHO) 2. Lipoproteins (Lipid) 3. Nucleoproteins (nucleic acid) 4. Chromoproteins (coloured substance) 5. Metalloproteins (metals such as $Fe, Zn, Cu$) 6. Phosphoproteins (phosphate).

What are structural proteins and what percentage of body weight do collagens represent?

Structural proteins include collagens, elastins, and keratins. Collagens represent $30\%$ of BW.

What are the functions of prostaglandins and leukotrienes?

They act as local messengers in inflammation.

Define the composition of the disaccharides Lactose, Sucrose, and Maltose.

Lactose (glucose + galactose); Sucrose (glucose + fructose); Maltose (glucose + glucose).

How is a milliequivalent defined in the context of inorganic substances?

A milliequivalent is one-thousandth of an equivalent. An equivalent weight is the weight in grams that will displace or react with $1\text{gram atomic weight of hydrogen ion}$ ($H^+ = 1.008\,g$).

Where is Stratified squamous epithelium typically located in the body?

Outer layer of skin, lining of the proximal portion of the GIT, and the lining of the ruminant forestomach.

What is the specific function and location of Transitional epithelium?

It allows organs to stretch and is found in the urinary bladder and ureters.

Distinguish between Merocrine, Apocrine, and Holocrine glands.

Merocrine glands are the most common; Apocrine glands include sweat glands; Holocrine glands are sebaceous glands.

What are the characteristics of Elastic connective tissue and where is a prominent example found?

It consists of kinked fibres that regain their original shape after stretching, such as the Ligamentum nuchae.

Define the three types of cartilage and their locations.

1. Hyaline (glass-like, found in bones within joints) 2. Fibrous (intervertebral disks, contains collagen fibres) 3. Elastic (external ear, contains elastic fibres).

What is the difference between Plasma and Serum?

Plasma is unclotted blood, while Serum is the fluid remaining after clotting and contains no clotting factors.

Classify the five types of Leukocytes (WBCs) into Granulocytes and Agranulocytes.

Granulocytes: neutrophils, basophils, and eosinophils. Agranulocytes: monocytes and lymphocytes.

How do Smooth, Skeletal, and Cardiac muscle differ in striation?

Smooth muscle is unstriated, while both Skeletal and Cardiac muscle are striated.

What are the primary components of a Neuron?

The cell body, axon, and dendrites; the neuron serves as the functional unit of nervous tissue.