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Forking larkspur (Delphinium consolida) or field larkspur as it is also known, is a highly poisonous annual or biennial herb of the family Ranunculaceae with a slender tap root and an erect, branched, leafy stem. The leaves are sessile, alternate and palmate with the segments finely divided. The flowers are blue and have a pronounced upward-curving spur which secrets nectar. The flowers are arranged in a terminal spike. The fruit is a follicle with flattened, black, pitted seeds.
 Research Forking Larkspur
The arrector pili is a smooth muscle of the skin. It is attached to a hair follicle just below its oil gland and extends upward on a slant to attach to the skin. The muscle reacts in response to cold or other stimuli. When it contracts, the muscle pulls the hair erect causing 'goose bumps'. At the same time, it squeezes the oil gland releasing a small amount of oil onto the skin.
Research Arrector Pili
Aspiration is a procedure used to obtain eggs from ovarian follicles for use in in-vitro fertilization. The procedure may be performed during laparoscopy, using a long needle and ultrasound to locate the follicle in the ovary. For the procedure, the woman is given hormone medications to stimulate the ovaries so that several mature eggs develop. After 36 hours, an ultrasound scan is used to view and locate the eggs. Special software allows the health care provider to view one ovum at a time and helps guide the needle through the vaginal wall towards the eggs, called ova, for removal. Usually several ova are removed at one time.
Research Aspiration
In the female, once a graafian follicle discharges its mature ovum, the cavity once occupied by the egg is replaced by luteal cells made of a yellow lipoid material. Together, the erupted graafian follicle and its clot of luteal cells compose the corpus luteum. If the ovum is fertilized, the corpus luteum will eventually create hormones which regulate the development of the placenta, the suppression of menstruation, the growth of the mammary glands, and the eventual development of more mature ova. If the ovum is not fertilized, the corpus luteum will become interpenetrated by blood capillaries and will eventualy disintegrate to leave a small scar tissue called the corpus albicans.
Research Corpus Luteum
The dermal papillae are small, nipple-like protrusions of the dermis that reach into the epidermis, bringing food and oxygen to the lower layers of epidermal cells. In addition, a papilla nourishes every hair follicle. Rows of papillae protruding from the dermis into the epidermis form ridges that create patterns on the skin of the hands, feet, and body. These papillary ridges on the fingertips are responsible for fingerprints. These ridges develop sometime before birth. Not only is the pattern unique for each individual, but also it never changes except to grow larger.
Research Dermal Papillae
A follicle is a small group of cells that surrounds and nourishes a structure such as a hair (hair
follicle) or a cell such as an egg (Graafian follicle).
Research Follicle
The Graafian Vesicles are numerous small globular transparent follicles found in the ovaries of mammals. Each follicle contains one ovum which is expelled when it reaches maturity.
Research Graafian Vesicles
The root of a hair has a bulbous shape and is called the hair bulb. It is located deep in the hair follicle. The hair bulb is whiter in colour, and softer in texture than the hair shaft.
Research Hair Bulb
The hair follicle is a tunnel-like segment of the epidermis that extends down into the dermis. The follicle is a thin sac of epidermal tissue with a bulb at the bottom. The hair follicles produce the hair. Every hair follicle is nourished by a papilla.
Research Hair Follicle
Hair shafts grow from hair follicles situated in the dermis and hypodermis. Every hair consists of a root, the part that lies under the skin, and a shaft, the part that extends from the follicle above the skin. Hair grows on every part of the skin except the palms of the hands and soles of the feet. Hair varies in length, thickness, and colour on different parts of the body and on different people. In some parts of the body, as in the skin of the eyelids, the hairs are so short that they do not to project beyond their follicles and on the face are fine, light sensory hairs called vibrissae. In other parts of the body, as on the scalp, the hair is much longer and thicker.
Research Hair Shaft
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The Probert Encyclopaedia was designed, edited and programed by
Matt and Leela Probert
©1993 - 2009 The Probert Encyclopaedia
Southampton, United Kingdom
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