Cell function

Question 1

Functions of cell wall

Answer 1

1. protect, support and shape of cell
2. Fully permeable (large spaces between microfibrils)

Question 2

functions of cytosol

Answer 2

1. provide a liquid env
2. Fills space between organelles

Question 3

phospholipids

Answer 3

differentially permeable to substances

Question 4

Cholesterol

Answer 4

Fluidity of cell membrane

Question 5

integral and peripheral proteins

Answer 5

1. Transport
2. Act as enzymes
3. Act as receptors
4. Attachment for cells
5. Inside cell membrane surface for attachment to cytoskeleton, which provides cell shape and cell motility

Question 6

Carbohydrates (glycocalyx)

Answer 6

1. mediate interactions btwn cells
2. Act as identifying markers
3. Blood type-absence or presence of antigenic substances on RBC surfaces

Question 7

Plasmalemma

Answer 7

1. Act as boundary btw cell and environment
2. Maintain integrity- diff permeable
3. Transport processes
4. Respond to externa signals
   -Hormone receptor
   -Recognize cells as innate or foreign
5. Coms and attachment with other cells
   - Excrete extra cellular mats
   -Cellular coms through the glycoproteins and glycolipids

Question 8

Nucleus

Answer 8

1. Contains DNA instructions
2. Protein synthesis
3. Control center that controls all activities

Question 9

Nuclear pore

Answer 9

Keeps DNA in and let mRNA out

Question 10

Chromosomes/Chromatin

Answer 10

Dna rep
transcription

Question 11

Nucleoli

Answer 11

Production of ribosomal RNA(rRNA)
and called the ribosome factory.
Ribosomal proteins are formed in the cytosol and move into nucleolus and bind with rRNA to form ribosomal sub units. They leave the nucleus and combine to form ribosomes

Question 12

ribosome

Answer 12

Protein synthesis - AA chain (polypeptide chain) to form protein
1, Polysomes and free ribosomes make protein
2. GER make protein

Question 13

endndoplasmic reticulum

Answer 13

Transport particles

Question 14

GER

Answer 14

1. Protein synthesis
2. Contains proteins in cisternae
3. Transport particles like proteins through the cell

Question 15

SER

Answer 15

1. Biosynthesis of steroid hormones
2. Regulate muscle contractions/concentration of Ca+
   3.In the liver
   - store and breakdown glycogen
   -syn of phospholipids
   -detoxification of poisons

Question 15

Golgi complex

Answer 15

Receives membrane bound secretory vesicles from GER
1. Change new proteins and glycoproteins
2. Packaging of proteins and enzymes (lysosomes) or cell membrane components
3. distribution of secretions in vesicles
-store finished products in cytoplasm or export outside plasmalemma

Question 16

peroxisomes

Answer 16

1. Synthesis and degradation of hydrogen peroxide
   2.Degrade fatty acids
   3.Metabolise toxins( in liver detoxify alcohol)
2. Bile acid synthesis

Question 16

Lysosomes

Answer 16

1.Food: macromolecules enter the cell via endocytosis enclosed in a vesicle. Lyso fuses w v and forms secondary lyso. Macromolecule digested to monomers and released into cytosol for utilization
2. Foreign subs: WBC engulf bacteria via vesicles through fusion and it’s digested by lysosomes
3. Old and worn-out cells -Autolysis- or old and worn-out cell components- autophagy: enclosed and digested by lysosomes

Question 17

Actin microfilament

Answer 17

2 actin chains in double helix and each chain contains globular proteins
1. Actin and myosin- helps for muscle contractions
2. Polymerize or depolymerize forming structural framework for a cell- eg 1) thin sheath- structural support, endocytosis, exocytosis, cell migratory activity eg2) form microvilli of epithelial cells of alimentary canal- can contract and lengthen the microvilli
3. ) Plays a role in shifting cytoplasmic components and cell movement– Amoeba- and cytoplasmic streaming and amoeboid movements

Question 17

Cytoskeleton

Answer 17

Supporting framework for organelles
maintains shape of cell
for cellular movement
anchors plasmalemma
supplies a surface for intracellular transport

Question 17

Mitochondria

Answer 17

aerobic respiration

Question 18

3 protein filaments of cytoskeleton

Answer 18

1. Microfilament
   2.Intermediate filament
   3.Microtubles

Question 19

Intermediate filaments

Answer 19

-Structural and strong alpha-keratin fiber network-3 strings of globular proteins
1) Form cytokeratin filaments(epithelial cells)
2) form neuro filaments (neurons)
3) Form Desmin filaments (heart muscle cells)

Question 20

Microtubules

Answer 20

Polymerize from globular protein subunits and can depolymerize easily. Like a tube
1) Forms spindles in mitosis and cell division
2) anchorage and reinforce organelles
3. Forms centrioles, basal bodies, cilia and flagella

Question 20

Centrioles and basal bodies

Answer 20

Types of microtubules 1) Give rise to basal bodies which forms cilia and flagella 2) Dtm plane along which cytoplasm will divide during cell division BASAL BODY Position Centrosome Structure 9+0 arrangement Originate from centrioles Function Give rise to cilia and flagella Centrosome Structure Short, microtubule Pair perpendicular to each other 9+0 arrangement Function Give rise to basal bodies Cell division

Question 21

cytology

Answer 21

study of cell function and structure

Question 21

How do big cells compensate for size

Answer 21

1. cytoplasmic streaming plant cells- organelles and fluids flow together and helps move molecules 2. Microvilli - inc SA for inc absorption 3. More than one nucleus to incr protein syn 4. Long, narrow, cylinder - nerve cells- cytoplasm near surface- quick diffusion

Question 21

cilia and flagella

Answer 21

cilia- casue mvement of liquid past stationary cells by moving back and forth to propel in one direction flagella- Propel motile cells which use flagellum as an oar for propulsion in fluid like sperm cell use 9+2 arrangement - 9 groups of 2 microtubules and 1 pair in the center

Question 21

resolving power

Answer 21

means resolution ability the ability to distinguish 2 point close to each other as sep pts

Question 22

Highway of the cell

Answer 22

endoplasmic reticulum

Question 22

cell

Answer 22

smallest structural and functional unit containing all molecules and structures NB for life

Question 22

cell doctrine

Answer 22

1. Life occurs from cells 2. Cells are self producing- cells come from cells 3. Structure relates to function

Question 22

Function of cells

Answer 22

1. Reproduction and growth 2. Respiration -oxidation 3. Contractibility 4. Absorption 5. metabolism 6. irritability/responsiveness 7. conductibility 8. Secretion and excretion

Question 23

Explain maximum & minimum size of cells in detail.

Answer 23

Max: * Natural laws limit upper cells size * Ineffective for biological communication * Slower diffusion * Ratio of nucleus to cytoplasm Min: * Any smaller won’t have space for necessary organelles to support life * Mycoplasm has +-200 organelles

Question 24

Repeatedly folded plates of memranes with spaces- tubles-vesicles-cisternae- enclosed

Answer 24

Endoplasmic reticulum

Question 25

control center

Answer 25

nucleus

Question 26

plant version of peroxisomes

Answer 26

glyoxysomes

Question 27

function of cristae

Answer 27

incre SA for ele transfer

Question 28

What is in matrix

Answer 28

ribosomes, enzymes, plasmid, cations

Question 29

how does the SER form

Answer 29

when GER loses ribosomes and starts synthesizing non protein products

Question 30

endomembrane system

Answer 30

flow of membranes between the different organelles (e.g. the nucleus or ER) and the plasmalemma, forming an endomembrane system involved in the synthesis of cell products, their modification in storage and eventually their final product (e.g. secretion).

Question 31

whats not included in the endomembrane system

Answer 31

mitochondria chloroplast peroxisomes

Question 32

cytoskeleton

Answer 32

an extended network of supporting filaments