Organs of Higher Order Animals

Packet #55

Chapter #

Introduction

Higher order animals, such as humans, contain multiple organs.

This packet investigates some of those organs.

Brain

Concentration of nerve tissue in the front or upper end of an animal's body.

It handles sensory information, controls motion, is vital to instinctive acts, and in higher vertebrates is the centre of learning.

Heart

Organ that pumps blood, circulating it to all parts of the body. The human heart is a four-chambered double pump with its right and left sides fully separated by a septum and subdivided on both sides into an atrium above and a ventricle below.

Kidney

One of a pair of organs that maintain water balance and expel metabolic wastes.

Bladder

The bladder is a storage vessel for urine and is lined by a special waterproof skin.

Liver

Largest gland in the body, with several lobes.

It secretes bile; metabolizes proteins, carbohydrates, and fats; stores glycogen, vitamins, and other substances; synthesizes coagulation factors; removes wastes and toxic matter from the blood; regulates blood volume; and destroys old red blood cells.

Lung

Either of two spongy, saclike respiratory organs in most vertebrates, occupying the chest cavity together with the heart and functioning to remove carbon dioxide from the blood and provide it with oxygen.

A similar organ in some invertebrates, including spiders and terrestrial snails.

Pancreas

A long, irregularly shaped gland in vertebrates, lying behind the stomach, that secretes pancreatic juice into the duodenum and insulin, glucagon, and somatostatin into the bloodstream.

Gallbladder

A small, pear-shaped muscular sac, located under the right lobe of the liver, in which bile secreted by the liver is stored until needed by the body for digestion.

Stomach

Digestive sac in the left upper abdominal cavity, which expands or contracts with the amount of food in it.

Intestines

Muscular hoselike portion of the gastrointestinal tract extending from the lower end of the stomach (pylorus) to the anal opening.

It is not only an organ of digestion (for that part of the process not completed by the stomach) but is the chief organ of absorption.

Spleen

Lymphoid organ, located in the left side of the abdomen behind the stomach.

The spleen is the primary filtering element for the blood, and it is a storage site for red blood cells (erythrocytes) and platelets.

Ovary & Uterus In zoology, the female reproductive

organ that produces eggs and sex hormones (estrogen and progesterone).

The uterus is an inverted-pear-shaped organ of the female reproductive system, in which the embryo and fetus develop during pregnancy.

Penis & Testes

The penis is the male sex organ, which also provides the channel for urine to leave the body.

The testes are the male reproductive organs that are oval-shaped, produce sperm and androgens (mainly testosterone) and are contained in a sac (scrotum) behind the penis.

Skin

Skin, the largest organ in the body, that acts as a physical barrier between the organism and its external environment, prevents water loss in dry conditions, hydration in humid or aquatic environments, and access to the body by microbes, and screening the harmful effects of ultraviolet rays of the sun.

Other Organs

Pituitary Gland

Thyroid

Adrenal Gland

Homework What are the functions

of those glands?