Week 5 - Lymphatic & Endocrine System Flashcards
Main 3 Functions of the Lymphatic System
Drains excess interstitial fluid
Transports dietary lipids
Immune responses
What is Lymph Fluid?
A collection of extra fluid that drains from cells and tissues and isn’t reabsorbed into your capillaries.
How do foreign substances get trapped in lymph nodes?
Reticular Fibres within the sinuses of the node
What does Lymph Fluid contain?
Contains proteins, minerals, fats, damaged cells, cancer cells and bacteria.
What cells help destroy foreign substances in lymph nodes?
Macrophages or lymphocytes
What is the role of lymph nodes in the immune system?
Function as a filtration system
Why is it important for lymph fluid to drain from cells and tissues?
crucial in maintaining fluid balance, removing waste products, supporting immune function, and facilitating fat absorption.
How does lymph travel through the lymph vessels?
Thoracic pressure, Smooth muscle contraction, and Skeletal muscle all contribute
What is the size of lymph nodes?
1 to 25mm in length
What structures divide the lymph node into compartments?
Trabeculae
What is the parenchyma of a lymph node divided into?
Superficial Cortex and a Deep Medulla
What are the two main regions of a lymph node’s interior?
reticular fibres and fibroblasts.
What type of cells are found in the inner cortex of a lymph node?
houses T cells
What type of cells are found in the outer cortex of a lymph node?
houses B cells
Name the key lymph nodes
Submandibular
Axillary
Mediastinal
Abdominal
Superficial Inguinal
Where does the submental lymph node drain lymph from?
Central area of the lower lip, the floor of the mouth and the apex of the teeth
What areas of the body does the Submandibular lymph node drain?
Collect lymph from the cheeks, the lateral and upper lip, lateral parts of the lower lip, gums and anterior tongue.
What regions of the body does the axillary lymph node drain?
breast, chest, abdomen above the level of the navel and skin of the upper limbs.
What are the main causes of interstitial fluid accumulation?
A result of pressure exerted from capillaries or from protein leakage into the tissues.
Where does lymph eventually return to the circulatory system?
via the left and right subclavian veins and into the vena cava.
How does a build-up of interstitial fluid affect blood volume and pressure?
Significant decrease it bc it inhibits the return of fluid into the capillaries
What is lymphedema?
A build-up of fluid in the body causes the affected tissue to become swollen.
Which lymph nodes are often removed in breast cancer surgery?
Axillary Nodes
What are the common symptoms of lymphedema in the elderly?
swelling, breakdown of the skin and ‘weeping’.
What are chylomicrons?
Chylomicrons are fatty acids that have been digested and converted within intestinal cells
What are lacteals?
They are Lymph drainage vessels that line the intestine and absorb the chylomicrons into the lymph fluid
What are glands made of ?
Epithelial
What are some Exocrine secretions?
earwax, mucus, saliva, digestive juices
How does exocrine distribute?
Through a duct or onto a specific tissue
How does Endocrine distribute?
Directly into the blood via ductless glands
where does exocrine secrete into
Into ducts
where does endocrine secrete into
Into Interstitial Fluid
What are the two types of hormones?
Lipid-based
Peptide-based
Name the Pituitary Hormones
Growth Hormone (GH)
Thyroid Stimulating Hormone (TSH)
Adrenocorticotrophic hormone (ACTH)
Prolactin (PRL)
Follicle-stimulating hormone (FSH)
Luteinising hormone (LH)
Oxytocin
Antidiuretic Hormone (ADH)
What does Growth Hormone (GH) do
Regulates metabolism and promotes tissue growth, especially bones and muscles
What does Adrenocorticotrophic hormone (ACTH) do
Stimulates adrenal cortex to secrete glucocorticoids
What does Thyroid Stimulating Hormone (TSH) do
Stimulates secretion of T3 and T4 from the thyroid gland and promotes growth
What does Prolactin (PRL) do
Stimulates growth of breast tissue
What does follicle-stimulating hormone (FSH)
Stimulates the production of sperm, secretion of oestrogen by ovaries, maturation of ovarian follicles, and ovulation.
What does Luteinising hormone (LH) do
Stimulates secretion of testosterone by the testes and stimulates the secretion of progesterone
What does Oxytocin do
Stimulates smooth muscle contraction in uterus, contraction of milk ducts
What does Antidiuretic Hormone (ADH) do
Increases permeability in distal convoluted tubules in kidneys, contacts smooth muscle contraction in small arteries
Where is the thyroid gland in the body?
At neck level with 5,6,7th cervical, and 1st thoracic vertebrae
Abnormalities of thyroid secretion
Hyperthyroidism
Hypothyroidism
Where does the adrenal gland secrete into?
Renal Blood Supply
Where does the adrenal gland secrete from?
the cortex and medulla
Process of negative feedback
- High blood glucose is detected
- Beta cells secure insulin
- Insulin gets glucose into cells
- Blood glucose is low
- Alpha cells secrete glucagon
- Glycogenolysis occurs and breaks down glycogen
What do alpha cells secrete glucagon?
Glucagon
What do beta cells secrete glucagon?
Insulin
