Biology-term 3 Flashcards
What is the heart responsible for?
The heart is a muscular pump that is responsible for moving blood throughout the circulatory system.
What is the outer layer of the heart and what does it consist of?
The outer layer of the heart is the pericardium and consists of two layers, the outer fibrous pericardium and inner serous pericardium.
What does the fibrous pericardium consist of?
It protects the heart
What does the serous pericardium consist of?
It contains an inner layer which forms a sac called the myocardium
What is the myocardium>
The thickest layer of heart tissue and a cardiac muscle
What are capillaries?
Fine channels with thin walls that allow for exchange of substances.
What is blood specialised for?
transport and defence
What is the role of blood in homeostasis?
- Transportation
- Regulation
- Defence
What are the components of blood?
Red blood cells, platelets, white blood cells.
What does blood carry?
Oxygen, nutrients and other essential compounds ti every living cell in the body.
Where in the blood is oxygen carried?
By the haemoglobin in the red blood cells
What is bloods relationship with waste products?
takes away from cells, transports hormones, white blood cells and platelets.
What does the blood regulate?
Regulates body temperature and fluid contents
What happens in the blood when the bodies dehydrated?
The plasma will leave the blood ti help maintain body fluid levels. But will absorb fluid if the body is saturated
What are platelets?
An important component of defence and provide the clotting factors found in blood
What is the purpose of the epithelial tissue in the small intestine?
Ridges and folds to increase surface area
What is the primary function of the digestive system?
To transfer nutrients, water and electrolytes from food into the animal bodies internal environment.
Why is ingested food essential?
Its an essential energy source from which the cells can produce ATP to carry out their particular energy-depended activities, such as active transport.
What are the main stages of food processing?
- Ingestion
- Digestion
- Absorption
- Elimination
What does respiration require?
The effective movement of air into and out of the lungs at an appropriate rate and volume to meet the body’s need at any particular time.
What does the upper respiratory tract consist of?
- The nostrils
- Nasal pharynx
- Pharynx (throat)
- Larynx (voice box)
- Trachea (windpipe)
What does the lower respiratory tract do?
Connects the lungs to the vascular system (blood)
What are the alveoli?
Tiny, thin walled sacs that are surrounded by networks of capillaries.
What happens when air is inhaled?
Oxygen moves through the upper respiratory system to eventually reach the alveoli, where it crosses the alveoli and capillary membranes into the blood system - at the same time, carbon dioxide moves from the bloodstream across the membranes into the alveoli, through the lungs and is exhaled.
What is excretion?
the movement of toxic materials, water, products of metabolism and excess materials from the body.
Why is excretion necessary?
To rid the body of waste products and to regulate volume and composition of body fluids.
What is metabolism?
The chemical process going on in the body to allow normal body functions.
What is the one type of waste that is not excreted by the body?
Faeces, which are egested.
What materials are excreted from the body?
- carbon dioxide
- Urea
- excess water
- Ions (Na, K, Cl)
- vitamins
- toxins
How is urea produced?
Produced when excess proteins and amino acids are broken down in the liver.
Why are the kidneys vital organs?
Part of the urinary system and are the main organ responsible for filtering the blood and excreting wastes.
What does the urinary system consist of?
- Right and left kidney
- Right and left ureters
- Urinary bladder
- Uretha
What is the outer portion of the kidney called?
The renal cortex
What is the inner portion of the kidney called?
The renal medulla