8/7/2019 Chapter 18 and 21

1/4

The G0 phase is A) the checkpoint before G1 B) the state of most cells in

an animal body C) another name for interphase D) a permanent state of allbody cells

Mitosis is controlled at the _____________ checkpoint. A) C B) G1

C) G2 D) M E) S

he spindle forms in the _____________ phase. A) C B) G1 C) G2

D) M E) S

The centromeres move toward the poles in _____________ . A) anaphase

B) interphase C) metaphase D) prophase E) telophase

Which of the following statements about mitosis is incorrect? A) The daughter nuclei

are genetically identical to the parent nucleus. B) Chromosomes separate duringanaphase due to the interaction of polar microtubules from opposite poles pushing against each

other. C) Chromosomes separate during anaphase when the kinetochore microtubules

shorten as they depolymerize. D) Chromosomes move to the metaphase plate using

motor proteins, a kind of kinesin, attached to spindle fibers. E) The centrosomes

organize the microtubules of the spindle fibers.

The cell cycle is controlled in most cells by A) time, after a certain length of time the

cell divides B) a series of checkpoints C) the completion of one phase which

triggers the beginning of the next D) cell size, when the cell reaches a certain size, it

divides E) different cells exhibit different control strategies, any of the 4 above can befound in eukaryotic organisms.

During synapsis A) sister chromatids pair all along their length B) sister

chromatids pair at the centromeres C) homologues repel each other except at the ends

D) homologues pair all along their length

Which of the following is not a unique feature of meiosis? A) synapsis B)

homologous recombination C) reduction division D) diakinesis

8/7/2019 Chapter 18 and 21

2/4

Of the following meiotic phases, ____ is most similar in behavior to the mitotic phase of the same

name. A) Prophase II B) Anaphase I C) Metaphase I D)None of the above

Sexual reproduction involves the alternation of A) mitosis and oogamy B)

isogamy and meiosis C) meiosis and fertilization D) meiosis and oogamy

E) mitosis and heterogamy

__________ distinguishes prophase from mitotic prophase. A) The number of

chromatids per chromosome B) Synapsis C) The number of homologues

D) Terminal chiasmata E) Synergistic complex

When crossing over is complete in prophase I, sister chromatids A) are fused together

by the synaptonemal complex B) are attached by their ends to the nuclear envelope

C) are held together near their common centromeres D) drift away from

each other E) are pulled toward the poles

If a zygote has 4 chromosomes, the somatic cells formed from it have _______________

chromosomes. A) 4 B) 8 C) 2 D) 1 E) 16

Which of the following are mismatched A) haploid-n B) somatic cells-2n

C) zygote-n D) sperm cell-n E) gamete-n

Biennial and perennial plants are stimulated to flower by exposure to low temperature. This is

called:a) photoperiodism b) florigenation c) chilling d) vernalization

A type of asexual reproduction in which parent organism simply divides into two daughterorganisms is:

a) budding b) multiple fission c) binary fission d) nuclear

fissionCocklebur(Xanthium), chrysanthemum, soyabean, tobacco, strawberry are examples of:

a) short day plants b) long day plants c) day-neutral plants d) nonePhytochromes

exist in two forms:a) P 660 and P 530 b) P 630 and P 730 c) P 660 and P 730 d) P 460 and P

730

Seed dormancy is special condition of rest, which enables an embryo to survive the long periods

8/7/2019 Chapter 18 and 21

3/4

of unfavourable environmental conditions such as:

a) water scarcity b) low temperature c) both a & b d) none

Short-day plants are really: 'a) short-night plants b) long-night plants c) mid-night plants d) mid-wife plants

Temperature around 4C stimulates the production of "Vernalin" hormone which induces:

a) vernalisation b) ovulation c) embryonic induction d) floweringThe ACTH released from foetal pituitary .stimulates the foetal adrenal gland to release:

a) steroids b) vasopressin c) corticosteroids d) oxytocin

The biological clock once stimulated causes production of florigen hormone in leaves, whichtravel through phloem to the floral buds, initiating:

a) fruiting b) leaf formation c) leaf shedding d) flowering

The duration of low temperature (Chilling) treatment varies from:

a) 4 days to 2 months . b) 4 days to 3 months c) 2 days to 3 months d) 5 days to5 months

The response to light intensity and quality leads to the discovery of a blue light sensitive protein

pigments,

a) phytoproteins b) phytochromes c) photochromes d) photonsThe variations in day length are called photoperiod and the phenomenon is called:

a) photoperiodism b) photosynthesis c) photo-variations d) photo-fluctuation

Plants have diplohaplontic life cycle'in:

'a). Asexual reproduction b). Sexual reproduction c). Both a & b d.) None

of these

Fruit ripening is often accompanied by a burst of respiratory activity called the:

a). Fertilization b). Photoperiod c.). Climatric d). ReproductionOrganisms produced from a single cell by sub-culturing (cloning) are called:

a). Identical twins b). Clones c). Similar d). None of these

The process which leads to union of gametes is:a. Germination b. Pollination c. Reproduction d. Fertilization

A structure established between the uterine and foetal tissues for the exchange of oxygen, carbon

dioxide, waste, nutrients and other materials is:a) bridge b) placenta c) canal d) channel

The yellowish glandular structure, corpus luteum, starts secreting a hormone called:

a). Sterone . b). Progesterone c). Oestrogen d.) Testerone

A type of asexual reproduction in which parent organism simply divides into two daughterorganisms is:

a) budding b) multiple fission c) binary fission d) nuclear

fissionDowns Syndrome (Mongolism) occurs in man, during which 21st chromosome fails to segregate, resulting

gamete with: a) 20 chromosomes b) 21 chromosomes c) 22 chromosomes d) 24

chromosomes

During Anaphase the separation of homologous chromosomes is:

a) random b) hit and miss c) arbitrary d) haphazard

Following the Gi is the' S-phase during which the DNA is synthesized and chromosomes number is:

a) doubled b) tripled c) four folded d) none

8/7/2019 Chapter 18 and 21

4/4

Full cell cycle in yeast cells is only: a) 15 minutes b) 30 minutes c) 60 minutes d) 90 minutes

G-i (Gap 1) is the period of: a) rest b) metabolic activity c) synthesis d)

movement

In anaphase I, in contrast to anaphase of mitosis, sister chromatids are not:

a) joined b) separated c) curled d) rotated

In case of human cell, cell cycle is about: a) 21 hours b) 22 hours c) 23 hours d) 24

hours

The paired chromosomes repel each other and begin to separate in:

a) leptotene b) zygotene c) pachytene d) diplotene,

In human cell mitosis takes 30 minutes, Gi, 9 hours, the S-phase 10 hours, and G2:

a) 2 hours . b) 3 hours c) 4 hours d) 4.5 hours

The individuals have additional sex chromosome in:

a) Klinefelter's Syndrome b) Turner's syndrome c) Down's syndrome d) Sach's

syndrome

The chromosomes become visible, shorten and thick in:a) leptotene . b) zygotene c) pachytene d) diplotene

The hereditary material is equally distributed in the daughter cell in:

a) meiosis b) mitosis c) amitosis d)

none

In non-disjunction chromosomes fail to segregate during:

a) prophase & metaphase b) anaphase & metaphase c) anaphase & telophase d) prophase &

telophase

Mitotic apparatus disorganize, nuclear membrane and nucleoli reorganize, forming two nuclei at two

poles of the cell in: a) prophase b) metaphase c) anaphase d) telophase

The affected individuals have pne missing X chromosome with only 45 chromosomes in:a) Klinefelter's Syndrome b) Turner's syndrome c) Down's syndrome d) Sach's

syndrome

Internal programme of events and sequence of morphological changes by which cell commit suicide is

collectively called as: a) suicidal attack b) necrosis c) apoptosis d)

autophagocytosis

Interphase can further be divided into:

a) G1-phase, S-phaseand G2-phase b) G1-phase, G2-phase and Gs-phase

c) S1-phase, S2-phase and S3-phase d) S1-phase, G-phase and S2-phase