Physiology Wk 1

Question 1

What is physiology

Answer 1

is the study of functions of living things

Question 2

What is a cell

Answer 2

the basic unit of life

Question 3

What are the basic cell functions

Answer 3

• obtaining food (nutrients) and o2 from the environment
• eliminating the cell’s environment carbon dioxide and other waste products
• synthesising proteins and other components needed for cell structure, growth, carrying out particular cell functions
• controlling the exchanging of materials between the cell and its surrounding environment and it being sensitive to changes in the environment
• reproducing (with exception of muscle and nerve cells that have limited reproductive capacity)

Question 4

what are specialised cell functions

Answer 4

• the gland cells of the digestive system secrete digestive enzymes that break down ingested food
• certain kidney cells can selectively retain the substances needed by the body while eliminating unwanted substances in the urine
• muscle cells generate tension by selective movement of internal structures which results in contraction
• nerve cells generate of transmit electrical impulses to other body regions

Question 5

what are the four types of tissue

Answer 5

• muscle tissue
• nervous tissue
• epithelial tissue
• connective tissue

Question 6

function of muscle tissue and three types of muscle tissue

Answer 6

• consists of cells specialised for contracting which generates tension and produces movement

skeletal muscle- moves the skeleton
cardiac muscle- pumps blood out of the heart
smooth muscle- controls movement of contents through hollow tubes and organs

Question 7

function of nervous tissue and where is nervous tissue found

Answer 7

• consists of cells specialised for initiating and transmitting electrical impulses
• electrical impulses act as signals that relay information from one part of the body to another. these are important for coordination, communication and control in the body

it is found in the brain, spinal cord, nerves and special sense organs

Question 8

function of epithelial tissue and its two types of structures

Answer 8

• cells specialised for exchanging materials between the cell and its environment

two types: epithelial sheets and secretory glands

Question 9

what do epithelial sheets do and what do secretory glands do

Answer 9

• epithelial sheets cover and line various parts of the body
• Glands are specialised for secreting and there are two types exocrine and endocrine

Question 10

what is secretion

Answer 10

secretion is the release from a cell in response to appropriate stimulation

Question 11

what is the function of exocrine glands

Answer 11

secrete through ducts to the outside of the body

Question 12

what is the function of endocrine glands

Answer 12

lack ducts and release their secretory products known as hormones internally into the blood

Question 13

what does connective tissue do

Answer 13

connects, supports and anchors various body parts
for example tendons which attach skeletal muscles to bones

Question 14

what are the four types of tissues known as

Answer 14

primary tissues

Question 15

how many body systems are there

Answer 15

11

Question 16

what is extracellular fluid made of

Answer 16

plasma
interstitial fluid which surrounds and bathes the cells

Question 17

what is homeostasis

Answer 17

Maintenance of a stable internal environement

Question 18

name the homeostatically regulated factors

Answer 18

• concentration of nutrients - constant supply for energy production
• concentration of o2 and co2- make sure acid forming co2 does not increase the acidity of the internal environment
• concentration of waste products
• changes in pH
• concentration of electrolytes, water, salt and other electrolytes
• volume and pressure
• temperature

Question 19

why is negative feedback important

Answer 19

a change in a homeostatically controlled factor triggers a response that seeks to restore the factor to normal to the opposite direction

Example when temperature monitoring detect a decrease in body temperature (below the desired level) it will send signals to the control centre in the brain which results in responses such as shivering

Question 20

what does positive feedback do

Answer 20

it enhances or amplifies a change so that the controlled variable continues to move in the direction of the initial change

The hormone oxytocin causes powerful contractions of the uterus (womb). As the contractions push the baby against the cervix the resultant stretching of the cervix triggers a sequence of events that brings about even more oxytocin, which causes even stronger uterine contractions