Interphase of Cell Cycle Video Lecture | Biology Class 11 - NEET

0:0:0: let's embark on an incredible journey of
0:0:2: interface in the cell cycle
0:0:4: interface makes up the majority of the
0:0:7: cell cycle and is divided into distinct
0:0:9: subfaces
0:0:11: in this video we will explore each of
0:0:13: its subfaces in detail and understand
0:0:15: their importance in the cell cycle
0:0:18: so let's begin
0:0:21: as we know that the human cell cycle
0:0:23: consists of two distinct phases
0:0:25: interface and in phase
0:0:27: interface is the longer of the two
0:0:29: lasting significantly longer than the M
0:0:32: phase as it is responsible for the
0:0:34: preparation of the cell for division
0:0:37: during interface the cell grows and
0:0:39: replicates its DNA in preparation for
0:0:42: the division that occurs in the end
0:0:43: phase
0:0:44: now let's have a look at both these
0:0:47: phases in detail
0:0:49: since these phases are quite complex we
0:0:52: divide them in substages to understand
0:0:54: them better
0:0:55: let's begin with the interface
0:0:58: first here is an image that depicts the
0:1:1: complete interface in general
0:1:3: as we can see the interface has three
0:1:5: stages G1 phase S phase G2 phase let's
0:1:9: begin each stage step by step
0:1:12: so as the cell enters the first stage of
0:1:15: the interface it's time for the first
0:1:17: Gap phase abbreviated as G1 phase
0:1:21: this phase is the interval between the M
0:1:23: phase of the previous cycle and the S
0:1:25: phase of the current cycle and it's the
0:1:28: first stage of the Preparatory phase
0:1:29: before DNA synthesis
0:1:32: during this phase the cell is still
0:1:34: metabolically active and grows in size
0:1:37: all the organelles duplicate and the
0:1:40: building blocks that will be required in
0:1:42: later stages are made
0:1:44: it's important to note that the G1 phase
0:1:47: does not involve DNA replication
0:1:50: so as the cell prepares for the
0:1:52: following stages its growing duplicating
0:1:54: its organelles and stockpiling materials
0:1:57: for the future
0:1:59: now students to make your preparation
0:2:1: easy and complete you should definitely
0:2:4: check out the notes of all the three
0:2:6: stages of interface
0:2:8: and the good news is eduriff provides
0:2:10: notes of all the chapter in detail
0:2:13: during the second stage of interface
0:2:15: known as the synthesis phase RS phase
0:2:18: and as the name suggests there will be
0:2:20: synthesis of something the nucleus and
0:2:23: its genetic material that is DNA is
0:2:25: synthesized or we can say duplicated in
0:2:28: this phase
0:2:29: but that's not all
0:2:31: there is one more important organelle
0:2:34: that gets duplicated in the S phase
0:2:36: which is centrosome which is a bundle of
0:2:38: threads present in the cell which also
0:2:41: gets duplicated
0:2:42: the centrosome contains smaller
0:2:44: organelles called centrioles made up of
0:2:47: microtubules which help in releasing the
0:2:49: threads required for separating sister
0:2:51: chromatids later
0:2:53: we will have a detailed look at this
0:2:55: process in our upcoming videos for now
0:2:58: all we need to know is that these
0:3:0: threads are important for the cell
0:3:2: division and for this reason duplication
0:3:4: of the bundle containing these threads
0:3:6: is also important
0:3:8: all this happens in the S phase so the S
0:3:11: phase takes up the responsibility of
0:3:13: duplicating the contents inside the
0:3:15: nucleus and the centrosome present in
0:3:17: the cytoplasm
0:3:19: now what's next
0:3:21: the next step in the process of the
0:3:23: interface is the second Gap phase
0:3:25: abbreviated as G to phase this phase
0:3:28: allows the cell to grow more along with
0:3:30: the enlargement in the cell size the
0:3:33: cell also makes more proteins and
0:3:34: organelles
0:3:36: the most important function of this
0:3:38: phase is that It prepares the cell for
0:3:40: mitosis
0:3:42: this phase helps the cell to prepare for
0:3:44: the actual cell division in the end
0:3:46: phase
0:3:47: so now I'll be set to study the next
0:3:50: phase that the ZM face
0:3:52: no not yet because we should know one
0:3:55: more intermediate step which plays an
0:3:57: important role whether the cell is going
0:3:59: to have the M phase or not
0:4:1: now are you curious to know about that
0:4:4: intermediate phase
0:4:6: this is the G naught phase an
0:4:8: intermediate phase between the M phase
0:4:10: that is cell division and the G1 phase
0:4:13: that is growth
0:4:14: also there are two types of G naught
0:4:17: phase equation phase and the senescent
0:4:19: phase
0:4:20: the quiescent phase is when the cell
0:4:22: temporarily stops dividing but can
0:4:25: return to the G1 phase if the external
0:4:27: or internal factors that caused it to
0:4:29: enter the G not phase are removed
0:4:32: on the other hand the senescent phase is
0:4:35: when the cell permanently stops dividing
0:4:38: the G naught phase is a metabolically
0:4:40: active phase where the cell is highly
0:4:43: active but it does not divide further
0:4:46: this phase is determined by a variety of
0:4:48: intrinsic and extrinsic factors such as
0:4:51: resource availability or nutritional
0:4:53: deprivation Etc
0:4:55: let's discuss an example to make you
0:4:58: clear about the G naught phase
0:5:0: so nerve cells are the example which
0:5:3: Entergy not face permanently they remain
0:5:6: metabolically active but do not divide
0:5:8: further in their entire life cycle as
0:5:11: they lack centrioles
0:5:13: so now you know what happens when a cell
0:5:15: stops dividing
0:5:17: fascinating isn't it
0:5:20: in our next video we will explore the
0:5:22: second phase of this fascinating process
0:5:24: of cell cycle the M phase
0:5:27: we will go over all the details and
0:5:30: explain everything you need to know in
0:5:32: an easy to understand way
0:5:34: so get ready to explore the M phase and
0:5:37: the Mysteries it holds we hope that you
0:5:40: have understood the topic
0:5:42: and now you should start studying this
0:5:44: chapter with the edurev app as you get
0:5:46: with your lectures notes variety of
0:5:49: questions and McQ tests for all the
0:5:52: chapters of each subject
0:5:54: it's like having the entire School in
0:5:56: your pocket