MIDSEM COMPILATION Flashcards
Name the reproductive method carried out by the bacterial cell
Binary fission
3 shapes of bacteria
Rod, spiral and spherical
What bonds is in WATER MOLECULE???
- O-H= IONIC BOND
2. H—–O = hydrogen bond
PHOTOSYNTHETIC PLANT CELL 7 structure and function !!!
- CELL WALL: For protection and shape of cell
- NUCLEUS: houses genetic material (DNA)
- NUCLEOLUS: supynthESISES RNA
- Chloroplast : contains chlorophyll for phosyntheis
- VACOULE: stores waste and h2 o
- MITOCHONDRION: produces energy in form of ATP ( cellular respiration)
- PLASMODESMATA: for communication and transport between adjacent cells
6 structure of bacterial cell + function
- PLASMID: circular DNA usually contain antibiotic resistant gene
- FIMBRIAE: Hairlike appendages for attachment
- FLAGELLA: movement
- CAPSULE: sticky layer for attachment
- ENDOSPORE: for bacteria to withstand harsh conditions
- CELL MEMBRANE: selective barrier, controls substance movement in and out of cell
What cellular structure from photosynthetic plant cell cannot be found in ANIMAL CELL??
Chloroplast and PLASMODESMATA
The chloroplast can be moved within cells to region with more sunlight. This is known as the Cytoplasmic streaming. NAME STRUCTURE RESPONSIBLE FOR THIS!!!!
Micro filament ( cytoskeleton component)
Label hydrogen bond that gives ADHESION!!
0-cellulose fiber surface
Label cohesion given from h bond
H2o——–H20
State one property of water that is due to hydrogen bond
Water has a high surface tension due to H bond
State monomer, polymer, bond, occurrence for BIOMOLECULE CARBOHYDRATE
- MONOMER- monosaccharides (glucose)
- BOND: glycosidic bond
POLYMER:
A) STARCH: plants only
B) CELLULOSE: plants only
C) GLYCOGEN: animals only
State monomer, polymer, bond, occurrence for BIOMOLECULE NUCLEIC ACID
- MONOMER: nucleotide
- POLYMER: DNA, tRNA, mRNA, rRNA
- Bond: phosphodiester bond
- Occurrence : ALL ORGANISMS
State monomer, polymer, bond, occurrence for BIOMOLECULE PROTEIN
- Monomer: Amino acid
- POLYMER: Protein
- Bond: PEPTIDE/ polypeptide
- Occurrence: in all organisms!!!
A triglyceride is formed from :
1 glycerol and 3 fatty acid tails
The three tails of a triglyceride are all
HYDROPHOBIC
What makes lipid UNSATURATED??
Carbon- carbon double bonds
Why are some lipids liquid???
Because molecules cannot pack tightly!!!
Difference between Amylose and amylopectin
AMYLOSE- single branch
AMYLOPECTIN: multiple branch
What linkages in amylose, amylopectin and glycogen have?
AMYLOSE: 1,4- linkage
AMYLOPECTIN AND glycogen : 1,4 & 1,6 linkage
Hydrolysis of polysaccharides can form monosaccharides for releasing energy. Which one ( amylose, amylopectin, glycogen)
Glycogen (MANY BRANCHES) would be quickest to release energy because it has more branches (surface area) allowing for hydrolysis to occur more thus faster.
Where is glycogen found and what is its function. What does it look like
Glycogen has more branches than amylopectin. It’s function is for energy storage.
What is function of cellulose
Structural support ( in cell wall)
Looks like P: ------ ------ ------
What two groups are in an a,into acid group???
- AMINO group (h-N-h)
2. Acid group (0=c-o-H)
When two amino acids are joined together by condensation reaction, they form
DIPEPTIDE BOND
If This amino acid cannot be synthesised in our body and has to be acquired by ingestion, then it is an
ESSENTIAL AMINO ACID
An amino acid can form ZWITTERION which bears a -&+ charge.
Z can be formed by donating its acidic hydrogen to amino group.
WHAT DIES IT LOOK LIKE????
HORIZONTAL: (NH+3) - C - (COO-)
Vertical: R-C-H
What is the biological significance for amino acid being a ZWITTERION
It can function like a buffer, donating H+ ions in alkaline solutions and accepting H+ ions in acidic solutions
Proteins have diff structures stabilised by diff bonds and interactions. Label!!!!
- PRIMARY: ( linear chain)
- SECONDARY: a- helix/ b-pleated sheet (short wiggle)
- TERTIARY: 3D structure stabilised by ionic, hydrogen, disulfur and hydrophobic interactions more wiggles) 1 chain of polypeptide
- QUATERNEY: 2 chains of polypeptide!!
4
Label diff bonds in tertiary structure of protein
- HPHOBIC: - ch3 (valine)
- H-BOND: -OH (serine)
- DISULPHATE: : -SH (cytesine)
- IONIC: O=C-O (aspartate)
What two groups is in monomer of DNA strand???
- P: phosphate group
2. S: pentose sugars/ deoxyribose
What is bond in DNA
Hydrogen bond
In bacterial genome, cytosine contributes to 22% of total number of nitrogenous bases in its double stair and DNA.
BASED on this info, what is % of guanine, adenine, thymine and uracil in this DNA? Present in table:
- GUANINE:22% (cytosine 22%)
- ADENINE AND THYMINE 28%
- Uracil: 0%
Number of strands in DNA and RNA
DNA:2
RNA :1
Function DNA
DNA is he genetic material in cell. It can direct the protein synthesis
Function RNA
- tRNA: to take up AMINO ACIDS in cytoplasm for protein synthesis
- mRNA: to TRANSFER genetic info from DNA to the ribosomes for translation
- rRNA: as a component of RIBOSOMES for protein synthesis
Label diagram of phospholipid bilayer
- PB
- Protein channel
- Protein
4, HPHILLIC heads - HPHOBIC tails
Why is phospholipid bilayer arranged like that???
Based on like dissolve like principle, phospholipids are oriented in such a way that hydrophilic heads are exposed to fluid ( cytoplasm), whilst hydrophobic tails face inwards, away from fluid contact
Why is membrane FLUID AND MOSAIC in nature???
FLUID: proteins and phospholipid moves laterally
MOSAIC: proteins are scattered across membrane
Give two examples to show that membrane being fluid is important to cell functioning:
- For cell growth
- For cell sealing ( ends and exocytosis)
Or
Cell division
Or phagocytosis
A student extracted protein by homogenising a small piece of liver with cold phosphate buffer. Explain why extracting protein requires COLD BUFFER
Cold: low temperature can prevent enzymes from denaturation
BUFFER: resist the. Hangs in pH, prevent enzymes from denaturation
Based on equation H2PO-4 H+ + HPO2-4. The H2-PO-4 is a
WEAK ACID BECAUSE!!
ACIDIC: There is more [h+] than [OH-] and
WEAK: does not dissociate completely (
A 10 cm long potato chip was placed in sugar solution . It’s length was measured in regular intervals over period 3 hours. Length decreased. EXPLAIN the change (3 points) of potatoo chip in first hour.
And WHY WAS THERE NO CHANGE IN LENGTH DURING (2.5-3.0 hour)????
- REGION OF HIGHER WATER CONC: POTATO CELLS!!
- Direction of net water movement : POTATO CELLS–> water
- Resulting cell appearance of potatoes: PLASMOLYSIS
2) no change in length because process reached equilibrium
The supermarket : lettuce and other produce is often sprayed with water. Per plain why this makes vegetables crisp. (3 points)
- Region of higher [water]: WATER
- Direction of NET water movement : water —> plants
- Resulting cell appearance in lettuce: TURGENT
CANNOT pass through membrane
- Haemoglobin (4 polypeptide chain)
- Glycogen
large molecules can’t pass
2 subs Can pass through membrane via phospholipid ( straight away)
1. Alcohol (non polar) 2 oxygen ( small)
3 subs require protein to pass membrane
- Carbon dioxide
- Sodium ion
- Water