Intro cont.

Question 1

What makes up an organ?

Answer 1

Tissues of varying types make up an organ.

The stomach, for example, is an organ as it consists of more than one tissue type. The outer layer of the stomach is comprised of connective tissue, the middle layer is muscle tissue, and the inner layer is epithelial tissue.

Organs have specific functions and usually have distinctive shapes.

Question 2

Several related organs, with a common function, make up a?

Answer 2

System.

For example, the cardiovascular system, responsible for circulating the blood around the body, consists of the heart, veins and arteries - all of which are organs, as they all comprise of more than one tissue type.

Question 3

What is the highest level of structural organization?

Answer 3

Organism.

All parts of the body (from the chemicals to the cells, tissues, organs and systems) are structured to function together to make up the organism - the living individual.

Question 4

For descriptive purposes, the body is split into regions, name them.

Answer 4

The head, neck, chest, abdomen, pelvis and the four limbs.

The abdomen is the area between the diaphragm and the pelvis. The chest, also called the thoracic area or thorax, is above the abdomen, the pelvis is below it.

Question 5

Name this textbook position:

Answer 5

This is called the anatomical position.

To describe the location of any body part, it is always assumed that the body is in the upright position, facing the observer, feet flat on the floor, arms at the sides, with the palms of the hands turned forward as shown here.

Question 6

The frontal view of the body is called what? This term is also used to describe the location of a body part in comparison to another.

The rear view is called what? Again this term is also used comparatively.

Answer 6

The anterior view.

The posterior view

Question 7

A part of the body that is positioned higher than another is said to be?

The lower part is referred to as?

Answer 7

A part of the body that is positioned higher than another is said to be superior.

The lower part is referred to as inferior.

Question 8

A body part nearer to the imaginary midline is said to be?

Moving away from the midline the part is said to be?

Answer 8

A body part nearer to the imaginary midline is said to be medial.

Moving away from the midline the part is said to be lateral.

These terms may also be used when the midline marks the centre line of an organ rather than the whole body.

Question 9

Terms used to describe the location of body parts within a limb, depends on the location in relation to where the limb attaches to the trunk of the body.

A part comparatively closer to where the limb attaches to the trunk is described as __________. A part comparatively further away from the point of attachment is ______ .

Answer 9

Proximal

Distal

Question 10

You will also see references to the body relative to planes.

A plane is an imaginary flat surface that passes through the body or an organ so you can see a cross section. Imagine a rectangular piece of glass slicing the body in two, so allowing you to view the parts of the structure through which it passes.

Name 3 common planes or sections:

Answer 10

1. The sagittal plane sections the body or an organ vertically into left and rightsides.
   
   • A sagittal plane does not have to split the body or organ into equal parts, but if the plane is down the midline, creating equal left and right sides, it is call a midsagittalplane. If the sides are unequal, it is called a parasagittal plane.
2. The transverse plane sections the body or an organ horizontally into superior(top) and inferior (bottom) sections.
3. The frontal plane sections the body or an organ into anterior (front) and posterior (back) sections.
4. Another plane you may occasionally come across is the oblique plane. An oblique plane passes through the body or organ at an angle.

Question 11

Buccal -

Calcaneal -

Cardiac -

Celiac / Coeliac -

Costal -

Crural -

Answer 11

Buccal - Mouth

Calcaneal - Heel

Cardiac - Heart

Celiac / Coeliac - Belly or intestines

Costal - Rib

Crural - Leg

Question 12

Cubital -

Cutaneous -

Gluteal -

Mammary -

Ophthalmic -

Palmar -

Answer 12

Cubital - Forearm

Cutaneous - Skin

Gluteal - Buttock

Mammary - Breast

Ophthalmic - Eye

Palmar - Hand

Question 13

Parietal -

Patellar -

Pectoral -

Pedal -

Perineal -

Popliteal -

Answer 13

Parietal - Outer wall of a body cavity

Patellar - Front of knee

Pectoral - Chest or Breast

Pedal - Foot

Perineal - Pelvic floor

Popliteal - Back of knee

Question 14

Plantar -

Sacral -

Umbilical -

Visceral -

Answer 14

Plantar - Foot

Sacral - Base of spine

Umbilical - Navel

Visceral - Organ or its covering

Question 15

Axillary -

Brachial -

Carpal -

Cephalic -

Cervical -

Cranial -

Digital -

Femoral -

Answer 15

Axillary - Armpit

Brachial - Arm

Carpal - Wrist

Cephalic - Head

Cervical - Neck

Cranial - Skull

Digital - Fingers/Toes

Femoral -Thigh

Question 16

Inguinal -

Lumbar -

Nasal -

Oral -

Orbital -

Otic -

Tarsal -

Thoracic -

Answer 16

Inguinal - Groin

Lumbar - Loin

Nasal - Nose

Oral - Mouth

Orbital - Eye

Otic - Ear

Tarsal - Ankle

Thoracic - Chest

Question 17

The human body is a highly specialized living structure. What life processes distinguished Living beings from non-living entities?

Answer 17

Metabolism - Chemical processes occur in a living being. All these chemical processes are referred to as metabolism.

Responsiveness - Living beings can detect and respond to changes in the internal and external environments.

Movement - There is movement in a living body, from single cells, tissues, individual organs and body systems to the whole structure.

Growth - The living body grows. It increases in both size and complexity.

Differentiation - Cells in the living body develop specialized functions. Specialized cells have structural and functional characteristics that differentiate them from their unspecialized ancestors.

Reproduction - The living body can reproduce new cells (for replacement and growth) and totally new individuals.

Question 18

1. To maintain life (characterized by _________(a)___________), the body needs a ________(b)________ environment. The internal environment is generally defined as the __________(c)____________.
2. The maintenance of a _____(b)________ environment is called what?

Answer 18

1 a) metabolism, responsiveness, movement, growth, differentiation and reproduction

b) stable internal
c) fluid that surrounds the cells.
2. homeostasis, literally meaning same/still (homeo/stasis).

Question 19

Optimum

For the cells to function efficiently, the composition of the surrounding fluids must be precisely maintained at all times. An organism is said to be in homeostasis when the internal environment is at optimum…. (3 things)

Answer 19

• contains the optimum concentration of gases, nutrients, ions and water
• is at the optimum temperature
• has an optimum volume for the health of the cells

Question 20

Any factor that causes an imbalance in homeostasis is referred to as?

Many external factors can affect homeostasis and create an imbalance and disturb the internal environment. Give examples:

Give examples of internal factors that affect homeostasis:

Answer 20

Stress

extremes of temperature or lack of oxygen

low blood-sugar level, pain or unpleasant thoughts

Question 21

It is clearly important that the body is capable of maintaining a state of homeostasis by rectifying imbalances quickly should they occur.

The body’s homeostatic responses are regulated by the ___(a)__ - in particular the ____(b)_____ - and the _____(c)_____ . These systems detect imbalances and then work to return the body to a state of homeostasis as soon as possible.

Answer 21

a) nervous system - b) hypothalamus
c) endocrine system

Question 22

The body works to maintain homeostasis using feedback systems.

1. Many body conditions are regulated by feedback systems, give examples:
2. In most cases, the response is required to reverse the situation. For example, if the blood pressure is detected as being too high, the feedback system responds by bringing about the necessary changes to reduce it. When the response reverses the original stimulus, the system is known as a ______?
3. Sometimes the feedback system increases the original stimulus. This is called a ________? This is less common, give one example:

Answer 22

1. Heart rate, breathing rate, blood pressure, blood-sugar level, pH and temperature.
2. negative feedback system. Negative feedback systems tend to regulate conditions that require frequent monitoring.
3. positive feedback system, One example of a positive feedback system is the control of contractions during labour. When labour begins, the stretching of the uterus causes the hormone oxytocin to be released into the blood. The oxytocin causes the uterus to contract, which pushes the baby further down the birth canal. This stretches the uterus further and consequently more oxytocin is secreted causing even stronger contractions.

Question 23

To control the internal temperature the body has to be able to both produce and lose heat.

Most of the heat produced by the body comes from the ___(a)__. ___(b)___ reactions break down the food and energy is released. Some of the energy released is used to form _____(c)________, The rest is released as ___(d)___.

Answer 23

a) digestion of food
b) Catabolic
c) adenosine triphosphate (ATP) the energy carrying molecule, used in every cell to capture and store energy.
d) heat.

Question 24

1. The rate at which heat is produced during the breakdown of nutrients is called the ?
2. Under normal conditions i.e quiet, resting, fasting body this is called the ?

Answer 24

1. metabolic rate.
2. basal metabolic rate (BMR). This is effectively the minimum of energy expenditure required to maintain the vital processes.

Question 25

What are the main factors that affect the metabolic rate - and therefore heat production? (Name 6)

Answer 25

1. Digestion - Metabolic rate increases when food is ingested, producing more heat.
2. Exercise - The metabolic rate increases during exercise, so increasing the body temperature. The chemical reactions that occur in the skeletal muscles during exercise are responsible for producing a great deal of heat.
3. Nervous System - When stressed the nerves release the hormonal neurotransmitter noradrenaline, which increases the metabolic rate.
4. Hormones - excreted from the thyroid during stressful situations cause an increase in the metabolic rate, as do adrenaline and noradrenaline (released from the adrenal glands). Testosterone (a male sex hormone produced in the testes) and growth hormone (produced and released by the pituitary gland) also increase the metabolic rate.
5. External Temperature - A high external temperature increases the internal body temperature. The higher the internal body temperature, the higher the metabolic rate.
6. Age - A child’s metabolic rate is approximately double that of an elderly person. This is due to the higher number of reactions taking place to facilitate growth.

Question 26

Think Physics rather than Biological

The heat produced in the body must be continuously removed. If it isn’t, the internal body temperature will increase and homeostasis will be lost.

Heat is lost from the body in a number of ways: name them:

Answer 26

1. Radiation - Heat is transferred as infra-red rays from the warmer body to a cooler object (e.g. ceiling, wall or floor), without physical contact.
2. Conduction - Heat is lost by conduction when the warmer body comes into physical contact with a cooler object (e.g. chair, clothing or air).
3. Convection - Heat is lost by convection when the warmer body comes into contact with a liquid or gas. The substance gets heated by conduction, expands and becomes less dense. The warmed substance then rises and is replaced.
4. Evaporation - Water evaporating from the skin takes much heat with it. Perspiring therefore helps to cool the body.

Question 27

1. What sort of mechanisms attempt to regulate body temperature, keeping a balance between heat production and heat loss?
2. What is the control centre for temperature regulation?

Answer 27

1. Homeostatic
2. The hypothalamus, an endocrine gland situated at the base of the brain. (It receives information from the heat receptors. If the body temperature is too low or too high, nerve impulses are sent from the hypothalamus to trigger responses that will help to return the body temperature back to normal. Temperature control is a negative feedback system.)

Question 28

What Physiological responses that may be triggered by the hypothalamus when the body temperature is detected as being too low:

Answer 28

• Constriction of the blood vessels (vasoconstriction) in the skin. This decreases the flow of warm blood to the skin so reducing heat loss.
• Erection of the hairs on the skin. This traps air that acts as an insulating layer.
• Stimulation of the adrenal glands to secrete adrenaline and noradrenaline. These hormones increase the metabolic rate, which consequently increases body temperature.
• Increased muscle tone. This instigates shivering, which increases body heat production.
• Stimulation of an increased production of thyroid hormones. Thyroid hormones increase the metabolic rate, so raising body temperature.

Question 29

What Physiological responses that may be triggered by the hypothalamus when the body temperature is detected as being too high:

Answer 29

• Blood vessels in the skin are dilated (vasodilation)
• metabolic rate and shivering are decreased.
• The sweat glands are stimulated to produce perspiration to increase the amount of heat lost by evaporation.