Cell Structure and organelles: The Structure of The Cell

The Structure of The Cell

Organelle	Structure	Function	Kind of cell found in?
Cell membrane (Plasma membrane)	Surrounds the cytoplasm and other organelle.	Allow things to enter and exit the cell; gets rid of waste	Both plant and animal cell
Cell Wall	Rigid; surrounds plant cells	Provides support, protection	Plant cell only.
Nucleus	Houses chromosomes/ DNA – the genetic code (heredity material)	Control center, tells other organelles what to do.	Both, plant and animal cells.
Cytoplasm	Gel- like liquid that fills the cell.	Provide suspension to organelles so they move around easier.	Both, plant and animal cells.
Mitochondrion (Single: Mitochondria)	Double membrane organelle with inner folds.	Converts glucose molecules into energy.	Both, plant and animal cells.
Chloroplast	Filled with chlorophyll; Contains stacks of discs	Site of photosynthesis- which makes food for plant cells.	Plant cell only.
Vacuole	Much larger in plant cells those animal cells.	Storage site of water, nutrient, and waste	Both, plant and animal cells.
Lysosome	Small, circular organelle that contains enzymes	Digest old cells parts; Aids with removal of waste.	Some plant and animal cells.

Table 1: The Structure and the function of the organelles.
Retrieved from https://studylib.net/doc/8654836/7.12d-cell-organelle-structure-vs-function

There are two cell types: prokaryotes and eukaryotes.

Difference between Prokaryotic and Eukaryotic Cell

Prokaryotic cell	CHARACTERISTIC	Eukaryotic cell
Small	Size	Large
Absent	Nucleus	Present
Contain single chromosome	Chromosomes	Contain more than one chromosome
Absent	Nucleolus	Present
Take place by fission or budding.	Cell Division	Occurs by mitotic and meiotic.
Made of peptidoglycan (Thickness of wall depends on whether the cell is Gram +ve or –ve)	Cell Wall	If present, made of cellulose (chitin in fungi)

Observation of animal cell and plant cell under light microscope and electronic microscope

Observation of plant cell under microscope

Observation of animal cell under microscope

Mitosis

Mitosis can divide the phase into 4 phase:

Prophase →→ Metaphase →→ Anaphase →→ Telophase

Figure 1: The Four Phase of Mitosis

Meiosis I AND II

Figure 3: The phases of meiosis

Difference between meiosis I and II
↓

Meiosis I

Differences

Meiosis II

Occurs prior to meiosis I	Interphase	Does not occur prior to meiosis II
Occurs	Replication of DNA and duplication of chromosomes	Does not occur
Occurs	Crossing over	Does not occur
Chromosomes arrange themselves at the equator in pairs	Metaphase	Chromosomes arrange themselves at the equator singly
Is halved	Chromosome number	Is maintained
Does not occur	Splitting of centromeres	Occurs
At the end of meiosis I	When the cell is haploid	Throughout meiosis II
Two	Number of the formed at the end	Four

Differences between Mitosis and Meiosis

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