CELL BIOLOGY Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

what are Cell requirements for life

A

Energy source
Light or chemical
Matter
Gases such as CO2 and O2
Simple nutrients
Monosaccharides, disaccharides, polysaccharides
Amino acids, fatty acids, glycerol, nucleic acids, ions and H2O
Removal of wastes
CO2, O2, urea, ammonia, uric acid, H2O, ions, metabolic heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

what is Field of View

A

The maximum area visible when looking through themicroscopeeyepiece (eyepieceFOV), usually quoted as a diameter measurement.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is Magnification

A

Magnification refers to the number of times larger an object appears compared to its actual size.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is Resolution

A

Resolution is the ability to distinguish between close together but separate object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

learn how to calculate magnetism- look in notebook

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

If you increase the magnification, how will it affect the field of view?

A

Increase field of view  decrease magnification

Decrease field of view  increase magnification

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

learn all the calculations and everything from the powerpoint

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

learn parts of a microscope from powerpoint

A
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Prokaryotic cells explain

A
Unicellular organisms
Simple cell structure
Small: 0.1–5.0 µm in diameter
Have a cell membrane and outer cell wall
Bacteria also have a capsule outside the cell wall
Many have a flagella for movement
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Prokaryotic cells (cont.)

A

Contains some organelles
But unlike eukaryotes, these organelles are not bound by a membrane
E.g. no proper nucleus, but still has DNA
Genetic material is mostly in a single circular DNA chromosome called a genophore.
There are also other smaller rings of DNA rings called plasmids.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Eukaryotic cells

A

Can be multicellular or unicellular
More complex cell structure
Large: 10-100 µm in diameter
Have a cell membrane and sometimes a cell wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Eukaryotic cells

A

Cell compartmentalisation
Organelles bound by internal membranes
E.g. nucleus, mitochondria, chroloplast

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Cell compartmentalisation

A

Multiple membranes mean that organelles can have a different internal composition from the surrounding cytosol and other organelles.
Allows processes that require different environments to occur at the same time, in the same cell
Allows relevant enzymes and reactants to be close together in high concentration and under the right conditions  high efficiency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what is cell membrane, nucleus, cytoplasm

A

one of the membranes of the cytoplasm which keeps it all together
-helps control what goes in and out of the cell
nucleus
-contains chromosomes where inherited info is stored
cytoplasm
-lots of membranes made from proteins and fats

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Purpose of the cell membrane

A

Provides a boundary between the extracellular and intercellular environment
Controls movement between the extracellular space (fluid) and the intracellular space (cytosol)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Phospholipid

A

Hydro: water

Philic: loving

Phobic: fearing
Phosphate end is polar and therefore hydrophilic (water-loving)
Fatty-acid side is non-polar and therefore hydrophobic (water-hating) – but is ok with non-polar liquids, e.g. oil.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Cholesterol

A

Stabilises the membrane
At high temps, stops membrane from being too fluid by restricting phospholipid movement
At low temps, stops membrane from being too solid by restricting tight packing of phospholipids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Glycoproteins

A

A type of molecule made up of a carbohydrate (sugar) linked to a protein that protrudes on the outer surface of the membrane.
Play important roles in cell adhesion and recognition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Protein channels

A

Proteins are embedded all throughout the cell membrane and play a wide variety of roles.
One of the most important uses are as transport channels.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Permeability

A
Cell membranes are said 
to be semi-permeable
◦ They allow solvent molecules 
to pass through, but prevent 
some of the solute molecules 
from doing so.
◦ Also known as selectively 
permeable.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What can pass through a

phospholipid bilayer?

A
Only molecules that are 
“accepted” in the inner 
hydrophobic (oily) region!
- Small, uncharged 
molecules
- Lipid-soluble molecule
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Diffusion

A

The movement of particles from an area of higher
to lower concentration
There is a concentration gradient
from one side to the other

23
Q

How to increase rate of diffusion

A

Increase concentration gradient
◦Increase temperature
◦ The higher the temperature, the faster particles move
◦Reduce size of particles
◦ Allowing faster travel through membranes
And vice versa, to slow down rate of diffusion

24
Q

Facilitated diffusion

A
Diffusion of molecules through a 
membrane via a proteins.
No energy is used
- Membrane has control over 
what crosses
- Protein can either just provide a 
path (channel) or bind to the 
molecule then unbind when its 
on the inside (carrier).
- This is the main way water 
passes the membrane.
25
Q

Active transport

A
When substances are transported across 
the membrane using energy, often 
against a concentration gradient.
◦ From low to high conc
◦ Always uses carrier proteins
◦ Crucial in allowing a cell to maintain an 
internal environment that differs from its 
external environment
26
Q

Bulk transport

A
Uses energy to allow movement of large, 
polar molecules across the membrane
◦Exocytosis
◦Endocytosis
◦ Pinocytosis (drinking)
◦ Entry of extracellular fluid and 
substances 
◦ Phagocytosis (eating)
◦ Entry of large particles like cell debris or 
bacteria
27
Q

Aquaporins

A

Protein channels that facilitate the diffusion of water through membranes

28
Q

Particles diffuse across the semi-permeable membrane, down the concentration gradient, until equilibrium is reached

A
29
Q

What if the solute particle cannot pass through the membrane?
Can equilibrium still be reached?

A

If water can still pass through the membrane, then it will move to achieve equilibrium!

30
Q

Osmosis

A

Osmosis is the net diffusion of water molecules across a semi-permeable membrane
Just like regular diffusion, but of water!
The concentration gradient is called an osmotic gradient
The pressure that causes the water to move along this gradient is called osmotic pressure.

31
Q

Water moves from hypotonic into hypertonic

A

Hypotonic:
The solution with the lower conc of solute
(and high conc of water)
Hypertonic:
The solution with the high conc of solute
(and lower conc of water)
Isotonic:
Both solutions have the same conc of solutes

32
Q

what is metabolism

A

the chemical reactions in the body’s cells that change food into energy

33
Q

what are the elements of cardiovascular system

A

Blood- the medium of transport
Heart- the pump
Vessels- the pathway

34
Q

Explain Blood

A

it is a complex mixture containing:
1. cells- RBS WBC Platelets
2. Plasma
RBCs are flattened discs which carry oxygen around the body.
Oxygen (O2) is held loosely by a protein called haemoglobin.
Haemoglobin has an iron molecule at its core, which gives it a red colour.
WBCs are much fewer in number.
They help protect the body against disease
Platelets are tiny cells which enable the blood to clot.
Plasma is a yellow liquid in which the cells float.

35
Q

Explain heart

A

The energy to move blood through the body is provided by the heart.
70 mL per beat
280 L per day
The heart begins beating in the embryo 3 wks after fertilisation
- from a tiny cluster of cardiac cells

36
Q

explain vessels

A
The pathway which carries the blood is a system of tubes called blood vessels
There are three major kinds of vessels:
	1. Arteries
	2. Veins
	3. Capillaries
37
Q

what are arteries

A
Arteries always carry blood AWAY from the heart.
Arteries:
	have a red-coloured lining
	have thick, muscular walls
	usually carry blood under high pressure
38
Q

what are veins

A
Veins always carry blood TO the heart.
Veins:
	have a bluish lining
	have thin walls
	usually carry blood under low pressure
39
Q

what are arteries

A

Arteries branch into smaller and smaller arterioles. Eventually they become capillaries, tiny vessels which reach into every tissue.
Capillaries branch into larger and larger venules, which then join to become veins.

40
Q

explain lymphatic system

A
The lymphatic system performs two roles:
	1. Circulation
	2. Disease resistance (immune response)
Since the heart is constantly pumping, fluid is always being pushed into body tissues. Without the lymphatic system, those tissues would swell up.
The lymphatic system has:
	1. Lymph 
		basically plasma (no cells)
	2. Lymph vessels 
		thin walled with valves
	3. Lymph ducts
		larger vessels which empty lymph into veins
	4. Lymph nodes
		bean-shaped lumps for lymph collection
		the location of WBC development
41
Q

how does fluid move throughout lymphatic system

A

Plasma leaves the blood stream, entering between tissue cells.
This intercellular fluid moves through the tissue, collecting wastes as it goes.
The fluid passes into lymph capillaries and is now called lymph.
Lymph moves along the vessels until it reaches a lymph node where WBCs destroy pathogens.
Lymph then moves through to a lymph duct, which returns the fluid to a large vein, completing the circuit.

42
Q

Respiratory system

A

In the human body there are two kinds of respiration:

1. Cellular respiration
2. Pulmonary respiration

Cellular respiration is a chemical process during which energy molecules are broken down.
Pulmonary respiration is the process by which gases are breathed in and out.

43
Q

2 major sections of respiratory system

A

The respiratory system has two major sections:

1. Upper respiratory system 
2. Lower respiratory system
44
Q

main parts of resp system

A

The nose and mouth are air entry points.
The pharynx connects the mouth with the trachea.
The epiglottis is a flap of tissue which prevents food going down the airway
The trachea is a rigid tube lined with cartilage
The lungs are spongy tissue made of tubes and sacs.
Alveoli (singular alveolus) are tiny sacs grouped in clusters at the end of the bronchioles.
They have very thin membranes and a high sa:vol.
They are supplied by a dense network of capillaries.
It is here that gas exchange occurs between air and the blood stream.
The diaphragm is a sheet of muscle separating the chest from the abdomen.
The inter-costal muscles join the ribs to each other

45
Q

Respiratory Process

A

Inter-costal muscles pull the ribs apart

The diaphragm contracts

These two actions expand the chest cavity, creating a lower pressure.

The lung tissues expand to fill the chest cavity

Air rushes in through the mouth & trachea (etc.)

During its passage down the airways, air is filtered by cilia, warmed and humidified
Once it reaches the alveoli, oxygen passes through the membrane into the blood in the capillaries

  1. At the same time, CO2 diffuses from the blood out into the alveoli
  2. The inter-costal & diaphragm muscles relax
  3. The chest cavity shrinks
  4. Air is expelled
46
Q

Respiratory Disease

A

Respiratory disease can be caused by:

1. Pathogens (e.g., bacteria)
2. Lifestyle impacts (e.g., smoking)
47
Q

Photosynthesis

A
Solar energy is converted to chemical bond energy in the process of photosynthesis. This bond energy is then released for cellular use via the process of respiration.
Photosynthesis occurs in chloroplasts.
occurs in two phases:
Phase 1: Light reactions
	- require sunlight energy
48
Q

what are autotrophs and heterotrophs

A

Organisms which construct their own energy storage molecules (‘food’) are called autotrophs.
Organisms which gather their energy from other organisms are called heterotrophs

49
Q

what are The two major energy storage molecules

A
The two major energy storage molecules in biological systems are glucose and ATP
Glucose
- quite small
	- quite stable
	- universal in the biosphere
	- not useable at the organelle level
ATP: 
	- adenosine tri-phosphate
	- ADP + P = ATP
	- the creation of the bond stores energy
	- breaking the bond liberates energy
	- ATP directly fuels organelle activity
50
Q

what is the photosynthesis equation

A

CO2 + H20 —— C6H12O6 + O2

51
Q

what are light and dark reaction

A

Light:
AKA “Light Dependent Reactions” as they require solar energy
Occur in the thylakoids of grana
Does not result in the production of sugar
Dark-
AKA ‘Light Independent Reactions’ as they occur constantly
Depend on the outputs of the light reactions
Occur in the stroma of the chloroplasts
Results in the formation of sugars
(CH2O)n
Process  Calvin Cycle

52
Q

what is visible light spectrum

A

The complete set of rainbow colours is known as the visible light spectrum.
The visible spectrum is itself only a small fraction of the complete electro-magnetic (EM) spectrum.
All EM energy, including light, moves in waves. The distance from the peak of one wave to the peak of the next is known as its wavelength

53
Q

why are plants green

A

Red light is absorbed most by chlorophyll, followed by blue light. they energise electrons and increase rate of photosynthesis
Green and yellow light are mostly reflected. This is the reason plants look green