Description : Write the function of each of the following (i)Middle piece in human sperm (ii)Tapetum in anthers (iii)Luteinising hormone in human males -Biology
Last Answer : (i)Middle piece in human sperm contains several mitochondria which produces energy for the motility of the sperm. (ii) Tapetum in anthers It is the innermost layer of the anther. ... male stimulates the Leydig cells to produce testosterone, necessary to complete the process of spermatogenesis.
Description : WHEN DO THE OOGENESIS AND THE SPERMATOGENESIS INITIATE IN HUMAN FEMALES AND MALES RESPECTIVELY ?
Last Answer : ANS. OOGENESIS AT THE FOETAL LIFEAND SPERMATOGENISIS STARTS AT PUBERTY.
Description : DESCRIBE THE PROCESS OF OOGENESIS IN HUMAN FEMALE AND DIFFERENTIATE IT WITH SPERMATOGENESIS ON THE BASIS OF TIME OF INITIATION AND THE PRODUCTS FORMED.
Last Answer : ANS. OOGENESIS : DIAGRAMMATIC REPRESENTATION AS GIVEN IN NCERT. DIFFERENCES BETWEEN : OOGENESIS SPERMATOGENESIS (i) STARTS DURING FOETAL LIFE (i) STARTS DURING PUBERTY (ii)PRODUCTS: OVUM (ii) SPERMS
Description : (a) IN WHICH PART OF HUMAN FEMALE REPRODUCTIVE SYSTEM DO THE FOLLOWING EVENTS TAKE PLACE. (i) RELEASE OF FIRST POLAR BODY (ii) RELEASE OF SECOND POLAR BODY (iii) FERTILISATION (iv) IMPLANTATION (b) NAME TWO HORMONES SECREATED ONLY DURING PREGNANCY.
Last Answer : ANS (a) (i) OVARY (ii) FALLOPIAN TUBE (iii) AMPULLA-ISTHAMUS JUNCTION OF FALLOPIAN TUBE (iv) ENDOMETRIUM LINING OF UTERUS (b) HUMAN CHORIONIC GONADOTROPIN AND HUMAN PLACENTAL LACTOGEN
Description : WRITE THE LOCATION AND FUNCTION OF SERTOLI CELLS IN HUMANS.
Last Answer : ANS. IN THE SEMINIFEROUS TUBULES OF TESTIS, NOURISHES DEVELOPING SPERMS.
Description : WHAT IS APOMIXIS? DESCRIBE ITS IMPORTANCE?
Last Answer : ANS. IT IS THE PROCESS OF DEVELOPMENT OF SEEDS WITHOUT FERTILISATION. EXAMPLE: SOME SPECIES OF ASTERACEAE AND GRASSES. IMPORTANCE: APOMICTIC GENES CAN BE INTRDUED IN HYBRID SEED INDUSTRY.
Description : (A) MENTION ANY FOUR STRATEGIES ADOPTED BY FLOWERING PLANTS TO PREVENT SELF-POLLINATION. (B) DEFINE THE TERM EMASCULATION.
Last Answer : ANS.(a) (i) SELF INCOMPATIBILITY (ii) PRODUCTION OF UNICELLULAR FLOWERS (iii) ANTHERS AND STIGMA ARE PLACED AT DIFFERENT POSITIONS. (iv) MATURATION OF ANTHER AND STIGMA IS NOT ... EMASCULATION: REMOVAL OF ANTHER BEFORE MATURITY SO AS TO ENSURE CROSS POLLINATION IN SELF POLLINATING FLOWERS.
Description : DESCRIBE THE CONTRACEPTIVE ACTIONS OF IUDs.
Last Answer : ANS. (i) INCREASES PHAGOCYTOSIS OF SPERMS (ii) SUPPRESS SPERM MOTILITY (iii) SUPPRESS FERTILISING CAPACITY OF SPERMS (iv) MAKES CERVIX HOSTILE TO SPERMS.
Description : DIFFERENTIATE BETWEEN MORULA AND BLASTULA STAGES OF MAMMALIAN EMBRYO.
Last Answer : ANS. MORULA: (i) 8 TO 16 CELLED STAGE EMBRYO (ii) SOLID WITHOUT ANY CAVITY BLASTULA: (i) 32 CELLED STAGE EMBRYO. (ii) HOLLOW WITH A CAVITY CALLED BLASTOCOEL
Description : WHAT IS CORPUS LUTEUM ? UNDER WHAT CONDITIONS DOES IT UNDERGO DEGENERATION ?
Last Answer : ANS. THE CORPUS LUTEUM IS FORMED IN THE MAMMALIAN OVARY FROM RUPTURED GRAAFIAN FOLLICLE AFTER OVULATION. IT DEGENERATES IN THE ABSENCE OF FERTILISATION, AS THE LEVEL OF FSH AND LH DROPS.
Description : STATE ONE ADVANTAGE AND ONE DISADVANTAGE OF CLEISTOGAMY.
Last Answer : ANS. ADVANTAGE: ASSURED SEED SET DISADVANTAGE: INBREEDING DEPRESSION.
Description : WHY IS THE PROCESS OF FERTILISATION IN A FLOWERING PLANT REFFERED TO AS DOUBLE FERTILISATION ?
Last Answer : ANS. DOUBLE FERTILISATION= SYNGAMY + TRIPLE FUSION SYNGAMY= ONE MALE GAMETE + EGG--- ZYGOTE(n) TRIPLE FUSION= ANOTHER MALE GAMETE+ POLAR NUCLEI-PRIMARY ENOSPERM NUCLEUS(3n)
Description : AT WHAT STAGE IS THE MAMMALIAN EMBRYO IMPLANTED IN THE UTERUS ?
Last Answer : ANS. AT THE BLASTOCYST STAGE.
Description : NAME THE PROTECTIVE SUBSTANCE PRESENT IN THE POLLEN ENVELOPE TO TIDE OVER ADVERSE CONDITIONS.
Last Answer : ANS. SPOROPOLLENIN.
Description : NAME THE TYPE OF FLOWER WHICH FAVOURS CROSS POLLINATION.
Last Answer : ANS. CHASMOGAMOUS.
Description : WHAT IS PERISPERM ?
Last Answer : ANS. THE RESIDUAL NUCELLUS, WHICH PERSISTS IN THE SEEDS IS CALLED AS PERISPERM.
Description : NAME THE PHENOMENON AND ONE BIRD WHERE THE FEMALE GAMETE DIRECTLY DEVELOPS INTO A NEW ORGANISM.
Last Answer : ANS. PARTHENOGENESIS, TURKEY.
Description : WHY ARE DATE PALMS REFFERED TO AS DIOECIOUS ?
Last Answer : ANS. BECAUSE THEY HAVE UNISEXUAL FLOWERS BORNE ON SEPARATE PLANTS.
Description : WHAT TERM IS GIVEN BY YOU TO THE GROUP OF INDIVIDUALS WHICH ARE GENETICALLY AND MORPHOLOGICALLY IDENTICAL ?
Last Answer : ANS. CLONE
Description : What is the role of luteinizing hormones in both males and females? -Biology
Last Answer : answer:
Description : A cross section at mid point of the middle piece of human sperm will show
Last Answer : A cross section at mid point of the middle piece of human sperm will show A. Centrioe, ... microtublues D. 9+2 arrangement of microtubules only.
Description : What has your experience with luteinizing hormone urine tests been?
Last Answer : You want to start using the tests or the hormones?
Description : Where is luteinizing hormone (LH) produced? -Biology
Description : What is the function of luteinizing hormone (LH)? -Biology
Description : Is luteinizing hormone a tropic hormone?
Last Answer : What is the answer ?
Description : The hormone measured in urine to test pregnancy is (A) Anterior pituitary luteinizing hormone (B) Androgen (C) Progesterone (D) Choroinic gonadotropin
Last Answer : Answer : D
Description : ACTH stimulates the secretion of (A) Glucocorticoids (B) Epinephrine (C) Thyroxine (D) Luteinizing hormone
Last Answer : Answer : A
Description : Growth hormone is released by (A) Somatostatin (B) Growth hormone releasing hormone (C) Prolactin release inhibiting hormone (D) Luteinizing releasing hormone
Last Answer : Answer : B
Description : Which of the following hormones is primarily responsible for stimulating the production of progesterone? a) Luteinizing hormone Luteinizing hormone is released by the pituitary gland. b) Follicle-stimulating ... , are involved in early development of the follicle and also affect the female libido.
Last Answer : a) Luteinizing hormone Luteinizing hormone is released by the pituitary gland.
Description : . Select the incorrect statement. (a) Human males have one of their sex-chromosome much shorter than other. (b) Male fruit fly is heterogametic. (c) In male grasshoppers, 50% of sperms have no sex-chromosome. (d) In domesticated fowls, sex of progeny depends on the type of sperm rather than egg.
Last Answer : (d) In domesticated fowls, sex of progeny depends on the type of sperm rather than egg.
Description : Fertilizin is a chemical substance produced from (a) polar bodies (b) middle piece of sperm (c) mature eggs (d) acrosome.
Last Answer : (c) mature eggs
Description : The middle piece of the sperm contains (a) proteins (b) mitochondria (c) centriole (d) nucleus.
Last Answer : (b) mitochondria
Description : Funtion of Malpighian tubules of cockroach :
Last Answer : Funtion of Malpighian tubules of cockroach : A. Digestion B. Respiration C. Excretion D. Reproduction
Description : In males, secretion of luteinising hormone is inhibited by (A) Gonadotropin releasing hormone (B) FSH (C) High blood level of testosterone (D) Inhibin
Last Answer : Answer : C
Description : In males, luteinising hormone acts on (A) Leydig cells (B) Sertoli cells (C) Prostate gland (D) All of these
Description : Write the function of each of the following (i)Seminal vesicle (ii)Scutellum (iii)Acrosome of human sperm -Biology
Last Answer : (i)Seminal vesicle spermatogenesis It secretes an alkaline fluid that helps in neutralising the acidity of the vaginal tract and thereby increase the lifespan of sperms. Secretion of seminal vesicle is ... which help the sperm enter into the cytoplasm of the ovum and thus helps in fertilisation.
Description : Luteinizing hormon (LH) in females
Last Answer : Luteinizing hormon (LH) in females A. Helphs in the appearance of secondary sexual characters B. ... from the ovary D. Controls the blood pressure
Description : All the following hormones use cAMP as a second messenger except (A) Estrogen (B) FSH (C) Luteinizing (D) Glucagon
Description : Which piece of a sperm is called power house ?
Last Answer : Which piece of a sperm is called power house ? A. Head piece B. Neck piece C. Middle piece D. Tail piece
Description : (i) Write the specific location and the functions of the following cells in human males Leydig cells Sertoli cells Primary spermatocyte (ii) Explain the role of any two accessory glands in human male reproductive system. -Biology
Last Answer : I)Oogenesis begins during the embryonic development stage when a million gamete mother cells (oogonia) are formed within each foetal ovary. (ii) (a) Sertoli cells are located on the inside ... provide nutrition to sperms. (b) Bulbourethral glands Their secretion helps in the lubrication of penis.
Last Answer : A hormone called testosterone.
Description : Which is an example of negative feedback? A) Nursing action stimulates the hypothalamus to release oxytocin that triggers mammary gland milk production. B) When the blood becomes dilute, ADH ... produce sperm or eggs. E) TRH stimulates the anterior pituitary to release thyroid-stimulating hormone.
Last Answer : B) When the blood becomes dilute, ADH is no longer released from the hypothalamus
Description : Thin cytoplasmic layer is present in middle part of sperm is called :-
Last Answer : Thin cytoplasmic layer is present in middle part of sperm is called :- A. Nebenkern B. Manchette C. Axial filament D. Zensen ring
Description : When did human males and females start to be discriminating with choice of mate?
Last Answer : Women.
Description : Why is a chart that shows human evolution with only males not representative?
Last Answer : Feel Free to Answer
Description : How are sex chromosomes of human males and females alike How are they different?
Last Answer : Need answer
Description : Haemophilia is more commonly seen in human males than in human females because (a) a greater proportion of girls die in infancy (b) this disease is due to a Y-linked recessive mutation (c) this ... to an X-linked recessive mutation (d) this disease is due to an X-linked dominant mutation.
Last Answer : this disease is due to an X-linked recessive mutation
Description : Seminal plasma in human males is rich in (a) fructose and calcium (b) glucose and calcium (c) DNA and testosterone (d) ribose and potassium.
Last Answer : (a) fructose and calcium