Cells - 5311

Question 1

Name the body systems

Give a brief description of each one

Answer 1

NICER DRUMS

Nervous system
The body is fast acting control system. Consists of brain, spinal-cord, nerves and sensory receptors

Integumentary
External Cameron at the body. Waterproof the body and protects the deeper tissues from injuries.

Cardiovascular
Use his blood as a transporting fluid to carry oxygen, nutrients, hormones and other substances, to and from tissue cells

Endocrine
Glands produce chemical molecules called hormones.

Respiratory
Keeps the body supplied with oxygen, removes CO2

Digestive
Basically a tube that runs through the body. The role is to break down food for dispersal into body cells and then the undigested food remains in the gastrointestinal tract so it can lead to body

Reproductive system
Primary goal is to produce offspring

Urinary
Helps maintain the body salt and water balance, regulating the acid base balance of the blood

Muscular
Has one for function, to contract and shorten

Skeletal
Supports body, provides framework that the skeletal muscles use to cause movement

Question 2

What is homeostasis

Answer 2

Dynamic state of equilibrium

The bodys ability to maintain a relatively stable internal environment

Question 3

Meaning for:
Homeo
Stasis

Answer 3

The same

Standing still

Question 4

What is positive feedback and negative feedback

Answer 4

Negative feedback acts to stop or reduce the stimulus i.e If the temperature is too high or acts to bring it down again. Most control mechanisms are negative

Positive feedback controls and frequent events, this tends to increase the original disturbance such as labour with contractions

Question 5

Explain the five survival needs for the body

Answer 5

Nutrients like food
Contains chemicals used for energy and sound building. Carbohydrates also a major energy providing fuel for the body

Oxygen
Nutrients are useless and his oxygen is available at cells can only survive a couple of minutes without it

Water
Amounts for 60 to 80% of the body weight

Temperature
Normal body temperature must be maintained to continue chemical reactions in the life sustaining rate. As the metabolism rate drops, at become slower and slower

Atmospheric pressure
The force exerted on the surface of the body by the weight of air, breathing and oxygen exchange depend on this

Question 6

What are the functions of a receptor, control Centre and effector in the homeostatic process

Answer 6

A receptor is the type of sensor that monitors and responds to changes in the environment

The controls centre determines the level at which a variable is maintained, analyses the information then determines the appropriate response or course of action

Effector: Provides the means for the response to the stimulus

Question 7

What are the three major cell regions

Answer 7

Nucleus: control centre, contains DNA

Cytoplasm: Essentially a factory area

Plasma membrane: A transparent barrier that contains the sales contents, separating them from the surrounding environment. It has a structure consists of two lipid layers with protein molecules flat

Question 8

What are the three elements of the cytoplasm

Answer 8

Cytosol - Semi transparent fluid that suspends the other elements

Organelles - Metabolism machinery of the cell, each type are specialised to carry out a certain function

Inclusions - Chemical substances that may or may not be present

Question 9

Explain these different cell types:
Fibroblast
Erythrocyte
Epithelial
Skeletal/smooth 
Fat cell
Macrophage
Nerve cell
Oocyte

Answer 9

Fibroblast. Abundant rough endoplasmic reticulum. Had a large Golgi apparatus to make or secrete protein protein blocks of fibres. Connects body balance

Erythrocyte - red blood cell. Carries O2 in the bloodstream

Epithelial - hexagonal shape allows epithelial cells to pack together in sheets

Skeletal/smooth - filled with abundant contractile filaments so they can shorten forcefully

Fat cell - produced by large lipid droplet in the cytoplasms

Macrophage - many lysosomes in the cell digest the infectious microorganisms it takes up

Nerve cell - neuron. Has long processes for receiving messages/transmitting them to other structures in the body.

Oocyte (female reproductive cell) - largest cell in the body, contains several copies of all organelles

Question 10

Describe the cellular membrane

Answer 10

Biological membrane that separates the interior of all cells from the outside environment

Question 11

Describe DNA

Answer 11

Deoxybutyric acid - Hereditary material in humans. Stored as a code made up of four chemical bases

Question 12

Describe endoplasmic reticulum

Answer 12

A system of fluid filled tubes or canals - A coil or twist through the cytoplasm. Mini circulatory system for the cell

Can be rough or smooth

Question 13

Describe the Golgi apparatus

Answer 13

Essentially a traffic director for cellular proteins

Its function is to modify and package proteins in certain ways

Question 14

Describe lysosomes

Answer 14

Membranous bags containing powerful digestive enzymes

Capable of digesting worn out or non-usable cell structures and most foreign substances

Question 15

Function of the mitochondria

Answer 15

Where ATP is produced

Question 16

Describe ribosomes

Answer 16

It’s a site of protein synthesis in the cell.

They are tiny dark body is made up of proteins. Some float free in the cytoplasm while others attached a rough endoplasmic reticulum

Question 17

Describe diffusion

Answer 17

The process where molecules move away from a region of high concentration to low concentration

Question 18

Describe osmosis

Answer 18

Diffusion of water through a selectively permeable membrane such as the plasma membrane

Question 19

Describe filtration

Answer 19

The process where water and solutes are forced through a membrane by fluid hydrostatic pressure. In the body, hydrostatic pressure is usually exerted by the blood

Question 20

What is active transport

Answer 20

Using ATP to energise the protein characters

Question 21

Describe Endocytosis

Answer 21

ATP requiring process. Moves substances into the sounds, take that extra cellular substances by and closing them in a small membrane vesicles.

Question 22

What is intersitital fluid

Answer 22

Fluid that continuously bathes the exterior of our sales

Question 23

What is intracellular fluid

Answer 23

Solution containing a small amount of gases

Question 24

What is a solvent

Answer 24

Substance present in the larger amount

Question 25

What is a solution

Answer 25

Homogeneous mixture of 2 or more components

Question 26

What are peroxisomes

Answer 26

Membranous sacs containing powerful oxidise enzymes that use molecular oxygen to detoxify a number of harmful or poisonous substances

Question 27

What is mitosis

Answer 27

Formation of 2 daughter nuclei with excatly the same genes as the mother nuclei

Question 28

Describe cell division process

What is the purpose of this?

Answer 28

Purpose - to produce more cells for growth and repair processes

Prophase.
Cell division begins - Chromogen threads shorten, chromosomes appear. The central separate from each other and move to opposite sides of the cell. By the end the nucleoli had broken down and disappeared, chromosomes have randomly attached to the spindle fibres by their centromeres

Metaphase.
Short stage - chromosomes cluster line up at this stage

Anaphase.
Centromeres that have held the chromatids together have split and begin to move slowly apart, drawn towards opposite ends of the cell. Stage is over when chromosomes stop moving

Telophase.
Opposite ends of the cell uncoil again

Question 29

What is a chromosome made up of

Answer 29

Made up of two strands each called a chromatoid, held together by a small button like body called a centromere